Moxa Technologies EtherDevice EDS-508A, EtherDevice EDS-505A, EDS-508A, EDS-505A User Manual

Moxa EtherDevice™ Switch

EDS-508A/505A Series User’s Manual

www.moxa.com/product

Fifth Edition, January 2010

 2010 Moxa Inc. All rights reserved.

Reproduction without permi ssion is pr ohibited.

Moxa EtherDevice™ Switch

EDS-508A/505A Series User’s Manual

The software described in this manual is furnished under a license agreement and may be used only in

accordance with the terms of that agreement.

Copyright Notice

Copyright  2010 Moxa Inc.

All rights reserved.

Reproduction without permi ssion is pr ohibited.

Trademarks

MOXA is a registered trademark of Moxa Inc.

All other trademarks or registered marks in this manual belong to their respective manufacturers.

Disclaimer

Information in this document is subject to change without notice and does not represent a commitment on the
part of Moxa.

Moxa provides this document “as is,” without warranty of any kind, either expressed or implied, including, but
not limited to, its particular purpose. Moxa reserves the right to make improvements and/or changes to this
manual, or to the products and/or the programs described in this manual, at any time.

Information provided in this manual is intended to be accurate and reliable. However, Moxa assumes no
responsibility for its use, or for any infringements on the rights of third parties that may result from its use.

This product might include unintentional technical or typographical errors. Changes are periodically made to the
information herein to correct such errors, and these changes are incorporated into new editions of the
publication.

Technical Support Contact Information

www.moxa.com/support

Moxa Americas:
Toll-free: 1-888-669-2872
Tel: [phone]
Fax: [phone]

Moxa China (Shanghai office)

:
Toll-free: 800-820-5036
Tel: [phone]
Fax: [phone]

Moxa Europe

:
Tel: [phone]
Fax: [phone]

Moxa Asia-Pacific

:
Tel: [phone]
Fax: [phone]

Table of Contents

Chapter 1 Introduction ...............................................................................................1-1

Inside the Future of Industrial Ethernet Technology ............................................................1-2

The trend in industrial communications and automation applications...................... 1-2

Industrial vs. Commercial......................................................................................... 1-2

Informative vs. Passive ............................................................................................. 1-2

Moxa EtherDevice™ Switch................................................................................................ 1-2

Package Checklist................................................................................................................. 1-3

Features ................................................................................................................................ 1-3

Chapter 2 Getting Started ..........................................................................................2-1

RS-232 Console Configuration (115200, None, 8, 1, VT100) ............................................. 2-2

Configuration using a T elnet Console.................................................................................. 2-5

Configuration using a Web Browser..................................................................................... 2-7

Disabling T elnet and Browser Access .................................................................................. 2-8

Chapter 3 Featured Functions...................................................................................3-1

Configuring Basic Settings................................................................................................... 3-3

System Identification................................................................................................. 3-3

Password ................................................................................................................... 3-4

Accessible IP............................................................................................................. 3-5

Port............................................................................................................................ 3-6

Network Parameters.................................................................................................. 3-8

Time........................................................................................................................ 3-10

Turbo Ring DIP Switches ....................................................................................... 3-13

System File Update—By Remote TFTP................................................................. 3-16

System File Update—By Local Import/Export....................................................... 3-17

System File Update—By Backup Media ................................................................ 3-18

Restart ..................................................................................................................... 3-18

Factory Default........................................................................................................ 3-19

Using Port Trunking........................................................................................................... 3-19

The Port Trunking Concept..................................................................................... 3-19

Configuring Port Trunking...................................................................................... 3-20

Configuring SNMP............................................................................................................. 3-22

SNMP Read/Write Settings..................................................................................... 3-23

Trap Settings ........................................................................................................... 3-24

Private MIB information......................................................................................... 3-25

Using Communication Redundancy................................................................................... 3-25

The Turbo Ring Concept......................................................................................... 3-26

Configuring “Turbo Ring” and “Turbo Ring V2”................................................... 3-31

The Turbo Chain Concept....................................................................................... 3-36

Configuring “Turbo Chain”..................................................................................... 3-37

The STP/RSTP Concept.......................................................................................... 3-40

Configuring STP/RSTP........................................................................................... 3-46

Using Traffic Prioritization................................................................................................. 3-48

The Traffic Prioritization Concept.......................................................................... 3-48

Configuring Traffic Prioritization........................................................................... 3-51

Using Virtual LAN............................................................................................................. 3-53

The Virtual LAN (VLAN) Concept........................................................................ 3-53

Sample Applications of VLANs using the EDS-508A/505A.................................. 3-56

Configuring Virtual LAN........................................................................................ 3-57

Using Multicast Filtering.................................................................................................... 3-60

The Concept of Multicast Filtering......................................................................... 3-60

Configuring IGMP Snooping.................................................................................. 3-63

Static Multicast MAC.............................................................................................. 3-65

Configuring GMRP................................................................................................. 3-66

GMRP Table ........................................................................................................... 3-66

Using Bandwidth Management.......................................................................................... 3-67

Configuring Bandwidth Management..................................................................... 3-67

Using Port Access Control.................................................................................................. 3-67

Configuring Static Port Lock .................................................................................. 3-69

Configuring IEEE 802.1X....................................................................................... 3-70

Using Auto Warning........................................................................................................... 3-73

Configuring Email Warning.................................................................................... 3-73

Event Type.............................................................................................................. 3-73

Email Setup............................................................................................................. 3-75

Configuring Relay Warning.................................................................................... 3-76

Event Setup ............................................................................................................. 3-76

Warning List............................................................................................................ 3-77

Using Line-Swap-Fast-Recovery........................................................................................ 3-78

Configuring Line-Swap Fast Recovery................................................................... 3-78

Using Set Device IP............................................................................................................ 3-78

Configuring Set Device IP ...................................................................................... 3-79

Using Diagnosis.................................................................................................................. 3-81

Mirror Port .............................................................................................................. 3-81

Ping ......................................................................................................................... 3-82

Using Monitor .................................................................................................................... 3-85

Monitor by Switch................................................................................................... 3-85

Monitor by Port....................................................................................................... 3-86

Using the MAC Address Tabl e........................................................................................... 3-86

Using Event Log................................................................................................................. 3-87

Using Syslog....................................................................................................................... 3-88

Using HTTPS/SSL ............................................................................................................. 3-89

Chapter 4 EDS Configurator GUI...............................................................................4-1

Starting EDS Configurator ................................................................................................... 4-2

Broadcast Search.................................................................................................................. 4-3

Search by IP address............................................................................................................. 4-4

Upgrade Firmware................................................................................................................ 4-4

Modify IP Address................................................................................................................ 4-5

Export Configuration............................................................................................................ 4-6

Import Configuration............................................................................................................ 4-7

Unlock Server....................................................................................................................... 4-8

Appendix A MIB Groups...............................................................................................A-1

Appendix B Modbus/TCP Map .....................................................................................B-1

EDS-505A Modbus information v1.0 ...................................................................................B-1

EDS-508A Modbus information v1.0 ...................................................................................B-7

1

1

Chapter 1 Introduction

Welcome to the Moxa EtherDevice Switch EDS-508A/505A Series, the Managed Redundant
Ethernet Switch designed specially for connecting Ethernet-enabled devices in industrial field
applications.

The following topics are covered in this chapter:

 Inside the Future of Industrial Ethernet Technology
 Moxa EtherDevice™ Switch
 Package Checklist
 Features

EDS-508A/505A Series User’s Manual Introduction

1-2

Inside the Future of Industrial Ethernet Technology

The trend in industrial communications and automation applications

As the world’s network and information technology becomes more mature, the trend is to use
Ethernet as the major communications interface in many industrial communications and
automation applications. In fact, a whole new industry has sprung up to provide Ethernet products
that comply with the requirements of demanding industrial applications.

Industrial vs. Commercial

Users have found that when moving Ethernet from the comfortable office environment to the harsh
and less predictable industrial environment, the commercial Ethernet equipment available in
today’s market simply cannot meet the high reliability requirements demanded by industrial
applications. This means that a more robust type of network equipment, commonly referred to as
industrial Ethernet equipment, is required for these applications.

Informative vs. Passive

Since industrial Ethernet devices are often located at the endpoints of a system, such devices
cannot always know what’s happening elsewhere on the network. This means that industrial
Ethernet communication equipment that connects these devices must take responsibility for
providing system maintainers with real-time alarm messages.

Moxa EtherDevice™ Switch

Moxa EtherDevice Switch comes with a suite of useful maintenance and monitoring functions, and
is designed to provide smooth and reliable operation in harsh industrial environments. You will
find that Moxa EtherDevice Switch establishes a new industrial Ethernet benchmark. It is excellent
for keeping automation systems running continuously, is ideal for sending status reports to help
prevent system damage and losses, is a great tool for mastering your industrial Ethernet networks,
and is well-suited for use with industrial device control networks.

ATTENTION

Throughout this User’s Manual, we use EDS as an abbreviation for Moxa EtherDevice Switch:

EDS = Moxa EtherDevice Switch

EDS-508A/505A Series User’s Manual Introduction

1-3

Package Checklist

The Moxa EtherDevice Switch EDS-508A/505A Series is shipped with the following items. If any
of these items are missing or damaged, please contact your customer service representative for
assistance.

 1 Moxa EtherDevice Switch EDS-508A/505A
 Hardware Installation Guide
 CD-ROM with User’s Manual and Windows Utility
 Moxa Product Warranty booklet
 RJ45 to DB9 Console port cable
 Protective caps for unused ports
 Panel mounting kit (optional—must order separately)

Features

 IPv6 Ready logo awarded (IPv6 Logo Committee certified).
 IEEE 1588 PTP (Precision Time Protocol) for precise time synchronization of networks.
 DHCP Option 82 for IP address assignment with different policies.
 Modbus/TCP industrial Ethernet protocol supported.
 Turbo Ring and Turbo Chain (recovery time < 20 ms at full load) and RSTP/STP (IEEE

802.1w/D).

 IGMP snooping and GMRP for filtering multicast traffic.
 Port-based VLAN, IEEE 802.1Q VLAN, and GVRP to ease network planning.
 QoS (IEEE 802.1p/1Q) and TOS/DiffServ to increase determinism.
 Port Trunking for optimum bandwidth utilization.
 IEEE 802.1X, HTTPS, and SSH to enhance network security.
 SNMPv1/v2c/v3 for different levels of network management.
 RMON for efficient network monitoring and proactive capability.
 Bandwidth management prevents unpredictable network status.
 Lock port function for blocking unauthorized access based on MAC address.
 Port mirroring for online debugging.
 Automatic warning by exception through e-mail, relay output.
 Digital inputs to integrate sensors and alarms with IP networks.

2

2

Chapter 2 Getting Started

This chapter explains how to access your EDS-508A/505A switch for the first time. There are
three ways to access the switch: serial console, Telnet console, and web browser. The serial
console connection method, which requires using a short serial cable to connect the EDS to a PC’s
COM port, can be used if you do not know the EDS’s IP address. The Telnet console and web
browser connection methods can be used to access the EDS over an Ethernet LAN, or over the
Internet.

The following topics are covered:

 RS-232 Console Configuration (115200, None, 8, 1, VT100)
 Configuration using a Telnet Console
 Configuration using a Web Browser
 Disabling Telnet and Browser Access

EDS-508A/505A Series User’s Manual Getting Started

2-2

RS-232 Console Configuration (115200, None, 8, 1, VT100)

NOTE

Connection Caution!

1. You cannot connect to the EDS simultaneously by serial console and Telnet.

2. You can connect to the EDS simultaneously by web browser and serial console, or by web

browser and Telnet. However, we strongly suggest that you do NOT use more than one
connection method at the same time. Following this advice will allow you to maintain better
control over the configuration of your EDS.

NOTE

We recommend using Moxa PComm Terminal Emulator, which can be downloaded free of
charge from Moxa’s website.

Before running PComm Terminal Emulator, use an RJ45 to DB9-F (or RJ45 to DB25-F) cable to
connect the EDS’s RS-232 Console port to your PC’s COM port (generally COM1 or COM2,
depending on how your system is set up).

After installing PComm Terminal Emulator, perform the following steps to access the RS-232
Console utility.

1. From the Windows desktop, click Start  Programs  PCommLite2.5  Terminal

Emulator.

2. Select Open under Port Manager to open a new connection.

EDS-508A/505A Series User’s Manual Getting Started

2-3

3. The Communication Parameter page of the Property window opens. Select the appropriate

COM port for Console Connection, 115200 for Baud Rate, 8 for Data Bits, None for Parity,
and 1 for Stop Bits.

4. Click the Terminal tab, and select VT100 for Terminal Type. Click OK to continue.

EDS-508A/505A Series User’s Manual Getting Started

2-4

5. Type 1 to select ansi/VT100 terminal type, and then press Enter.

6. The Console login screen will appear. Press Enter to open the Account pop-up selector and

then select either admin or user. Use the keyboard’s down arrow to move the cursor to the
Password field, enter the Console Password (this is the same as the Web Browser password;
leave the Password field blank if a console password has not been set), and then press Enter.

7. The EDS-508A/505A’s Main Menu will be displayed. (NOTE: To modify the appearance of

the PComm Terminal Emulator window, select Font… under the Edit menu, and then choose
the desired formatting options.)

EDS-508A/505A Series User’s Manual Getting Started

2-5

8. After entering the Main Menu, use the following keys to move the cursor, and to select

options.

Key Function

Up/Down/Left/Right arrows, or Tab Move the onscreen cursor
Enter Display & select options
Space Toggle options
Esc Previous Menu

Configuration using a Telnet Console

You may use Telnet to access the EDS’s console utility over a network. To be able to access
EDS’s functions over the network (by Telnet or Web Browser) from a PC host that is connected to
the same LAN as the EDS, you need to make sure that the PC host and the EDS are on the same
logical subnet. To do this, check your PC host’s IP address and subnet mask . By default, the
EDS’s IP address is 192.168.127.253 and the EDS’s subnet mask is 255.255.0.0 (for a Class B
network). If you do not change these values, and your PC host’s subnet mask is 255.255.0.0, then
its IP address must have the form 192.168.xxx.xxx. On the other hand, if your PC host’s subnet
mask is 255.255.255.0, then its IP address must have the form 192.168.127.x xx.

NOTE

To use the EDS’s management and monitoring functions from a PC host connected to the same
LAN as the EDS, you must make sure that the PC host and the EDS are on the same logical
subnet.

NOTE

Before accessing the console utility by Telnet, first connect one of the EDS’s RJ45 Ethernet ports
to your Ethernet LAN, or directly to your PC’s Ethernet NIC. You can establish a connection
with either a straight-through or cross-over Ethernet cable.

NOTE

The EDS-508A/505A’s default IP is 192.168.127.253.

EDS-508A/505A Series User’s Manual Getting Started

2-6

Perform the following steps to access the console utility by Telnet.

1. Click Start  Run, and then telnet to the EDS’s IP address from the Windows Run window.

(You may also issue the telnet command from the MS-DOS prompt.)

2. Type 1 to choose ansi/vt100, and then press Enter.

3. The Console login screen will appear. Press Enter to open the Account pop-up selector and

then select either admin or user. Use the keyboard’s down arrow to move the cursor to the
Password field, enter the Console Password (this is the same as the Web Browser password;
leave the Password field blank if a console password has not been set), and then press Enter.

4. When the Main Menu of the EDS’s console utility opens, click Terminal  preferences…

from the menu at the top of the window.

5. When the Terminal Preferences window opens, make sure that the VT100 Arrows option is

selected.

NOTE

The Telnet Console looks and operates in precisely the same manner as the RS-232 Console.

EDS-508A/505A Series User’s Manual Getting Started

2-7

Configuration using a Web Browser

The EDS’s web browser interface provides a convenient way to modify the switch’s configuration
and access the built-in monitoring and network administration functions. The recommended web
browser is Microsoft Internet Explorer 5.5 or 6.0 wi t h JVM (Java Virtual Machine) installed.

NOTE

To use the EDS’s management and monitoring functions from a PC host connected to the same
LAN as the EDS, you must make sure that the PC host and the EDS are on the same logical
subnet.

NOTE

If the EDS is configured for other VLAN settings, you must make sure your PC host is on the
management VLAN.

NOTE

Before accessing the EDS’s web browser interface, first connect one of its RJ45 Ethernet ports to
your Ethernet LAN, or directly to your PC’s Ethernet NIC. You can establish a connection with
either a straight-through or cross-over Ethernet cable.

NOTE

The Moxa EDS-508A/505A’s default IP is 192.168.127.253.

Perform the following steps to access the EDS’s web browser interface.

1. Open Internet Explorer and type the EDS’s IP address in the Address field. Press Enter to

establish the connection.

2. The web login page will open. Select the login account (Admin or User) and enter the

Password (this is the same as the Console password), and then click Login to continue. Leave
the Password field blank if a password has not been set.

EDS-508A/505A Series User’s Manual Getting Started

2-8

NOTE

By default, the EDS’s password is not set (i.e., is blank).

You may need to wait a few moments for the web page to be downloaded to your computer. Use
the menu tree on the left side of the window to open the function pages to access each of Moxa
EtherDevice Switch’s functions.

Disabling Telnet and Browser Access

If you are connecting the EDS to a public network, but do not intend to use its management
functions over the network, we suggest disab li ng both Telnet Console and Web Configuration
from the RS-232 Console’s Basic Settings  System Identification page, as shown in the
following figure.

3

3

Chapter 3 Featured Functions

This chapter explains how to access the EDS-508A/505A’s various configuration, monitoring, and
administration functions. There are three ways to access these functions: RS-232 console, Telnet
console, and web browser. The serial console connection method, which requires using a short
serial cable to connect the EDS to a PC’s COM port, can be used if you do not know the EDS’s IP
address. The Telnet console and web browser connection methods can be used to access the EDS
over an Ethernet LAN, or over the Internet.

The Web Console is the most user-friendly way to configure the EDS. In this chapter, we use the
Web Console interface to introduce the functions. There are only a few differences between the
Web Console, Serial Console, and Telnet Console.

The following topics are covered in this chapter:

 Configuring Basic Settings
 Using Port Trunking
 Configuring SNMP







 Using C

ommunication Redundancy

 Using Traffic Prioritization
 Using Virtual LAN
 Using Multicast Filtering
 Using Bandwidth Management
 Using Port Access Control
 Using Auto Warning
 Using Line-Swap-Fast-Recovery
 Using Set Device IP
 Using Diagnosis
 Using Monitor
 Using the MAC Address Table

EDS-508A/505A Series User’s Manual Featured Functions

3-2

 Using Event Log
 Using Syslog
 Using HTTPS/SSL

EDS-508A/505A Series User’s Manual Featured Functions

3-3

Configuring Basic Settings

The Basic Settings group includes the most commonly used settings required by administrators to
maintain and control the EDS.

System Identification

The system identification items are displayed at the top of the web page, and will be included in
alarm emails. Entering the system identification information makes it easier to identify the
different switches connected to your network.

Switch Name

Setting Description Factory Default

Max. 30
Characters

This option is useful for specifying the role or
application of different EDS units.
E.g., Factory Switch 1.

Managed Redundant Switch
[Serial No. of this switch]

Switch Location

Setting Description Factory Default

Max. 80
Characters

To specify the location of different EDS units.
E.g., production line 1.

Switch Location

Switch Description

Setting Description Factory Default

Max. 30
Characters

Use this to enter a more detailed description of
the EDS.

None

Maintainer Contact Info

Setting Description Factory Default

Max. 30
Characters

To provide information about whom to contact
in order to resolve problems. Use this to enter
contact information of the person responsible
for maintaining this EDS.

None

EDS-508A/505A Series User’s Manual Featured Functions

3-4

Web Auto-logout (s)

Setting Description Factory Default

60 to 86400 (seconds)

Disable or extend the auto-logout time for the
web management console.

0 (disable)

Age time (s)

Setting Description Factory Default

15 to 3825 (seconds)

The length of time that a MAC address entry
can remain in the Moxa switch. When an
entry reaches its aging time, it “ages out” and
is purged from the switch, effectively
cancelling frame forwarding to that specific
port.

300

Password

The EDS provides two levels of access privileges: admin privilege gives read/write access to all
EDS configuration parameters, and user privilege provides read access only. You will be able to
view the configuration, but will not be able to make modifications.

ATTENTION

The EDS’s default Password is not set (i.e., is blank). If a Password is already set, then you will
be required to type the Password when logging into the RS-232 Console, Telnet Console, or Web
Browser interface.

Account

Setting Description Factory Default

admin “admin” privilege allows the user to modify all

EDS configuration settings.

user “user” privilege only allows viewing the EDS

configurations.

admin

EDS-508A/505A Series User’s Manual Featured Functions

3-5

Password

Setting Description Factory Default

Old Password
(Max. 16 Characters)

Type current password when changing the
password

None

New Password
(Max. 16 Characters)

Type new password when changing the password None

Retype Password
(Max. 16 Characters)

If you type a new password in the Password field,
you will be required to retype the password in the
Retype new password field before updat ing the
new password.

None

Accessible IP

The EDS uses an IP address-based filtering method to control access to EDS units.

Accessible IP Settings allows you to add or remove “Legal” remote host IP addresses to prevent
unauthorized access. Access to the EDS is controlled by IP address. If a host’s IP address is in the
accessible IP table, then the host will be allowed access to the EDS. You can allow one of the
following cases by setting this parameter:

 Only one host with the specified IP address can access the EDS

E.g., enter “192.168.1.1/255.255.255.255” to allow access to just the IP address 192.168.1.1.

 Any host on a specific subnetwork can access the EDS

E.g., enter “192.168.1.0/255.255.255.0” to allow access to all IPs on the subnet defined by this
IP address/subnet mask combination.

EDS-508A/505A Series User’s Manual Featured Functions

3-6

 Any host can a ccess the EDS

Disable this function by deselecting the Enable the accessible IP list option.
The following table shows additional configuration examples:

Allowable Hosts Input format

Any host Disable

192.168.1.120 192.168.1.120 / 255.255.255.255

192.168.1.1 to 192.168.1.254 192.168.1.0 / 255.255.255.0

192.168.0.1 to 192.168.255.254 192.168.0.0 / 255.255.0.0

192.168.1.1 to 192.168.1.126 192.168.1.0 / 255.255.255.128

192.168.1.129 to 192.168.1.254 192.168.1.128 / 255.255.255.128

Port

Port settings are included to give the user control over Port Access, Port Transmission Speed,
Flow Control, and Port Type (MDI or MDIX). An explanation of each configuration item follows:

Enable

Setting Description Factory Defaul t

checked Allows data transmission through the port.
unchecked Immediately shuts off port access.

enabled

ATTENTION

If a connected device or sub-network is wreaking havoc on the rest of the network, the Disable
option under Advanced Settings/Port gives the administrator a quick way to shut off access
through this port immediately.

EDS-508A/505A Series User’s Manual Featured Functions

3-7

Description

Setting Description Factory Defaul t

Media type Displays the media type for each module’s port N/A

Name

Setting Description Factory Defaul t

Max. 63 Characters Specify an alias for each port, and assist the

administrator in remembering important
information about the port.
E.g., PLC 1

None

Speed

Setting Description Factory Defaul t

Auto Allows the port to use the IEEE 802.3u protocol

to negotiate with connected devices. The port and
connected devices will determine the best speed

for that connection.
100M-Full
100M-Half
10M-Full
10M-Half

Choose one of these fixed speed options if the

opposing Ethernet device has trouble

auto-negotiating line speed.

Auto

FDX Flow Ctrl

This setting enables or disables the flow control capability of this port when the “port transmission
speed” setting is in “auto” mode. The final result will be determined by the “auto” process
between the EDS and connected devices.

Setting Description Factory Defaul t

Enable Enables flow control for this port when in

auto-negotiate mode.
Disable Disables flow control for this port when in

auto-negotiate mode.

Disable

MDI/MDIX

Setting Description Factory Defaul t

Auto Allows the port to auto detect the port type of the

opposing Ethernet device and change the port

type accordingly.
MDI

MDIX

Choose the MDI or MDIX option if the opposing

Ethernet device has trouble auto-negotiating port

type.

Auto

EDS-508A/505A Series User’s Manual Featured Functions

3-8

Network Parameters

The Network configuration allows users to config ure both IPv4 and IPv6 parameters for
management access over the network. This Moxa Ethernet switch supports both IPv4 and IPv6,
and can be managed through either of these address types. An explanation of each configuration
item follows.

IPv4

The IPv4 settings include the switch’s IP address and subnet mask, as well as the IP address of the
default gateway. In addition, input cells are provided for the IP addresses of a 1st and 2nd DNS
server.

IPv6

IPv6 setting includes two distinct address types – Link-Local Unicast address and Global Unicast
address. A Link-Local address makes the switch accessible over IPv6 for all devices attached to
the same local subnet. To connect to a larger network with multiple segments, the switch must be
configured with a Global Unicast address.

EDS-508A/505A Series User’s Manual Featured Functions

3-9

Global Unicast Address Prefix (Prefix Length: 64 bits)

Setting Description Factory Default

Global Unicast Address
Prefix

The prefix value must be formatted according
to RFC 2373 “IPv6 Addressing Architecture,”
using 8 colon-separated 16-bit he xadeci mal
values. One double colon may be used in the
address to indicate the appropriate number of
zeros required to fill the undefined fields.

None

Global Unicast Address

Setting Description Factory Default

None Display IPv6 Global Unicast address.

The network portion of Global Unicast
address can be configured by specifying the
Global Unicast Prefix and using a EUI-64
interface ID in the low order 64 bits. The host
portion of Global Unicast address is
automatically generated using the modified
EUI-64 form of the interface identifier
(Switch’s MAC address)

::

EDS-508A/505A Series User’s Manual Featured Functions

3-10

Link-Local Address

Setting Description Factory Default

None

The network portion of Link-Local address is
FE80 and the host portion of Link-Local
address is automatically generated using the
modified EUI-64 form of the interface
identifier (Switch’s MAC address)

FE80 :: (EUI-64
form of the MAC
address)

Neighbor Cache

Setting Description Factory Default

None

The information in the neighbor cache that
includes the neighboring node IPv6 address,
the corresponding Link-Layer address, and
current state of the entry.

None

Time

The Time configuration page lets users set the time, date, and other settings. An explanation of
each setting is given below the figure.

The EDS has a time calibration function based on information from an NTP server or user
specified Time and Date information. Functions such as Auto warning “Email” can add real-time
information to the message.

EDS-508A/505A Series User’s Manual Featured Functions

3-11

NOTE

The EDS does not have a real time clock. The user must update the Current Time and Current
Date to set the initial time for the EDS after each reboot, especially when the network does not
have an Internet connection for an NTP server or there is no NTP server on the LAN.

Current Time

Setting Description Factory Default

User adjustable time. The time parameter allows configuration of the

local time in local 24-hour format.

None (hh:mm:ss)

Current Date

Setting Description Factory Default

User adjustable date. The date parameter allows configuration of the

local date in yyyy/mm/dd format.

None

(yyyy/mm/dd)

Daylight Saving Time

Daylight saving time (also know as DST or summer time) involves advancing clocks (usually 1
hour) during the summer time to provide an extra hour of daylight in the afternoon.

Start Date

Setting Description Factory Def au l t

User adjustable date.

The Start Date parameter allows users to
enter the date that daylight saving time
begins.

None

End Date

Setting Description Factory Default

User adjustable date.

The End Date parameter allows users to
enter the date that daylight saving time
ends.

None

Offset

Setting Description Factory Default

User adjustable hour.

The offset parameter indicates how many
hours forward the clock should be
advanced.

None

System Up Time

Indicates the EDS’s up time from the last cold start. The unit is seconds.

Time Zone

Setting Description Factory Default

User selectable time zone The time zone setting allows conversion

from GMT (Greenwich Mean Time) to
local time.

GMT (Greenwich
Mean Time)

EDS-508A/505A Series User’s Manual Featured Functions

3-12

NOTE

Changing the time zone will automatically correct the current time. You should configure the
time zone before setting the time.

Time Server IP/Name

Setting Description Factory Default

1st Time Server IP/Name IP or Domain address (e.g., 192.168.1.1 or

time.stdtime.gov.tw or time.nist.gov).

2nd Time Server IP/Name

The EDS will try to locate the 2nd NTP Server
if the 1st NTP Server fails to connect.

None

Time Server Query Period

Setting Description Factory Default

Query Period This parameter determines how frequently the

time is updated from the NTP server.

600 seconds

EDS-508A/505A Series User’s Manual Featured Functions

3-13

IEEE 1588 PTP

The following information is taken from the NIST website at http://ieee1588.nist.gov/intro.htm:
Time measurement can be accomplished using the IEEE Standard for a Precision Clock

Synchronization Protocol for Networked Measurement and Control Systems (IEEE 1588-2008) to
synchronize real-time clocks incorporated within each component of the electrical power system
for power automation applications.

IEEE 1588, which was published in November 2002, expands the performance capabilities of
Ethernet networks to control systems that operate over a communication network. In recent years
an increasing number of electrical power systems have been using a more distributed architecture
with network technologies that have less stringent timing specifications. IEEE 1588 generates a
master-slave relationship between the clocks, and enforces the specific timing requirements in
such power systems. All devices ultimately get their time from a clock known as the grandmaster
clock. In its basic form, the protocol is intended to be administration free.

Turbo Ring DIP Switches

The Turbo Ring DIP Switch page allows users to disable the four DIP switches located on the
EDS’s outer casing. When enabled, the DIP switches can be used to configure basic settings for
either the “Turbo Ring” protocol or “Turbo Ring V2” protocol. A complete description of the
settings is given below.

NOTE

The proprietary “Turbo Ring” protocol (recovery time < 300 ms) was developed by Moxa in
2003 to provide better network reliability and faster recovery time for redundant ring topologies.
The “Turbo Ring V2” protocol (recovery time < 20 ms), which was released in 2007, supports
additional redundant ring architectures.

In this manual, we use the terminology “Turbo Ring” ring and “Turbo Ring V2” ring to
differentiate between rings configured for one or the other of these protocols.

For a detailed description of “Turbo Ring” and “Turbo Ring V2,” please refer to the Using
Communication Redundancy section later in this chapter.

How to Enable or Disable the Turbo Ring DIP Switches

EDS-508A/505A Series User’s Manual Featured Functions

3-14

Disable the Turbo Ring DIP Switch

Setting Description Factory Default

Enable the Turbo
Ring DIP
Switches

The four DIP switches are enabled when the
“Disable the Turbo Ring DIP Switch” box is
not checked.

Disable the Turbo
Ring DIP
Switches

The four DIP switches are disabled when the
“Disable the Turbo Ring DIP Switch” box is
checked.

Not checked (i.e., the
Turbo Ring DIP Switches
are enabled by default)

Set DIP switch as Turbo Ring / Set DIP switch as Turbo Ring V2

Setting Description Factory Default

Set DIP switch as
Turbo Ring

Select this option to enable the Turbo Ring DIP
switches to configure the EDS for a “Turbo
Ring” ring.

This is the default if you do
NOT reset the switch to
factory default settings
(provided you upgraded the
firmware for Turbo Ring
V2).

Set DIP switch as
Turbo Ring V2

Select this option to enable the Turbo Ring DIP
switches to configure the EDS for a “Turbo
Ring V2” ring.

This is the default if you
DO reset the switch to
factory default settings
(provided you upgraded the
firmware for Turbo Ring
V2).

NOTE

If you upgrade the firmware of your EDS from Turbo Ring to Turbo Ring V2, but do no t re set the
switch to factory defaults, the DIP switches will be set to configure the EDS for a “Turbo Ring”
ring. If you reset the switch to factory defaults, the DIP switches will be set to configure the EDS
for a “Turbo Ring V2” ring.

How to Configure the Turbo Ring DIP Switches

The Turbo Ring DIP Switches are set to the OFF position at the factory.

NOTE

The four DIP Switches are used to configure both the “Turbo Ring”
and “Turbo Ring V2” protocols, depending on which protocol is
active. To select which protocol the EDS will use, start the user
interface software, and then use the left menu to navigate to the
Communication Redundancy page. To use one of the Turbo Ring
protocols for the EDS, select either “Turbo Ring” or “Turbo Ring V2”
in the Redundancy Protocol drop-down box. See the Configuring
“Turbo Ring” and “Turbo Ring V2” section in thi s chapter for
details.

12

------

MASTER

COUPLER

TURBO
RING

34

The following tables show how to use the DIP switches to configure the EDS for “Turbo Ring” or
“Turbo Ring V2.”

NOTE

DIP switch 4 must be set to the ON position to enable DIP switches 1, 2, and 3. If DIP switch 4 is
set to the “OFF” position, then DIP switches 1, 2, and 3 will all be disabled.

EDS-508A/505A Series User’s Manual Featured Functions

3-15

“T urbo Ring” DIP Switch Settings

DIP 1 DIP 2 DIP 3 DIP 4

ON: Enables this EDS
as the Ring Master.

ON: Enables the
default “Ring
Coupling” ports.

ON

: Activates DIP
switches 1, 2, 3 to
configure “Turbo
Ring” settings.

Reserved for future
use.

OFF

: This EDS will
not be the Ring
Master.

OFF

: Do not use this
EDS as the ring
coupler.

OFF

: DIP switches 1,

2, 3 will be disabled.

“Turbo Ring V2” DIP Switch Settings

DIP 1 DIP 2 DIP 3 DIP 4

ON: Enables the
default “Ring
Coupling (backup)”
port.

ON

: Enables this EDS

as the Ring Master.

ON: Enables the
default “Ring
Coupling” port.

ON

: Activates DIP
switches 1, 2, 3 to
configure “Turbo Ring
V2” settings.

OFF: Enables the
default “Ring
Coupling (primary)”
port.

OFF

: This EDS will
not be the Ring
Master.

OFF

: Do not use this

EDS as a ring coupler.

OFF: DIP switches 1,
2, 3 will be disabled.

NOTE

The DIP 1 setting will only be active if DIP 3 is in the ON position. If you set DIP 3 to OFF, then
the default Ring Coupling port will NOT be enabled, even if DIP 1 is ON.

Protocol Default Turbo Ring Ports Default Ring Coupling Port(s)

Tur bo Ring

EDS-505A

: ports 4 and 5

EDS-508A

: ports 7 and 8

EDS-505A

: ports 2 and 3

EDS-508A

: ports 5 and 6

Tur bo Ring V2

EDS-505A

: ports 4 and 5

EDS-508A

: ports 7 and 8

EDS-505A

: port 2

EDS-508A

: port 5

NOTE

The Turbo Ring Ports and Coupling Ports will be added automatically to all VLANs if you set
DIP Switch 4 to the “ON” position.

NOTE

If you do not enable any of the EDS-508A/505A switches to be the Ring Master, the Turbo Ring
protocol will automatically choose the EDS-508A/505A with the smallest MAC address range to
be the Ring Master. If you accidentally enable more than one EDS-508A/505A to be the Ring
Master, these EDS-508A/505A switches will auto-negotiate to determine which one will be the
Ring Master.

EDS-508A/505A Series User’s Manual Featured Functions

3-16

NOTE

If you use the browser interface to enable the DIP switches (by un-checking the “Disable the
Turbo Ring DIP switch” checkbox), and then flip DIP switch 4 from ON to OFF, the Ring Ports
and Coupling Ports that were added to all VLANs will be restored to their previous software
settings. (For details, please refer to the “Using Virtual LANs” section of this manual).

System File Update—By Remote TFTP

The EDS supports saving your configuration file to a remote TFTP server or local host to allow
other EDS switches to use the same configuration at a later time, or saving the Log file for future
reference. Loading pre-saved firmware or a configuration file from the TFTP server or local host
is also supported for easy upgrading or configuration of the EDS.

TFTP Server IP/Name

Setting Description Factory Default

IP Address of TFTP
Server

The IP or name of the remote TFTP server. Must be
set up before downloading or uploading fil es.

None

Configuration Files Path and Name

Setting Description Factory Default

Max. 40 Characters The path and file name of the EDS’s configuration

file in the TFTP server.

None

Firmware Files Path and Name

Setting Description Factory Default

Max. 40 Characters The path and file name of the EDS’s firmware file. None

Log Files Path and Name

Setting Description Factory Default

Max. 40 Characters The path and file name of the EDS’s log file None
After setting up the desired path and file name, click Activate to save the setting, and then click

Download to download the prepared file from the remote TFTP server, or click Upload to upload
the desired file to the remote TFTP server.

EDS-508A/505A Series User’s Manual Featured Functions

3-17

System File Update—By Local Import/Export

Configuration File

To export the configuration file of this EDS, click Export to save it to the local host.

Log File

To export the Log file of this EDS, click Export and save it to the local host.

NOTE

Some operating systems will open the configuration file and log file directly in the web page. In
such cases, right click Export to save as a file.

Upgrade Firmware

To import the firmware file of this EDS, click Browse to select the firmware file already saved on
your computer. The upgrade procedure will proceed automatically after clicking Import.

Upload Configuration Data

To import the configuration file of this EDS, click Browse to select the configuration file already
saved on your computer. The upgrade procedure will proceed automatically after clicking Import.

EDS-508A/505A Series User’s Manual Featured Functions

3-18

System File Update—By Backup Media

Auto load system configurations when system boots up

Setting Description Factory Default

Enable

Enables Auto load system configurations when
system boots up

Disable

Disables Auto load system configurations when
system boots up

Enable

Save the current configurations to ABC

To export the current configuration file of the EDS, click on Save to save it to the ABC.

Load the ABC’s configurations to the Switch

To import the configuration file of the EDS, click on Load to load it to the Switch.

Restart

This function is used to restart the Moxa EtherDevice Switch.

EDS-508A/505A Series User’s Manual Featured Functions

3-19

Factory Default

The Factory Default function is included to give users a quick way of restoring the EDS’s
configuration settings to their factory default values. This function is available in the Console
utility (serial or Telnet), and Web Browser interface.

NOTE

After activating the Factory Default function, you will need to use the default network settin gs to
re-establish a web-browser or Telnet connection with your EDS.

Using Port Trunking

Link Aggregation allows one or more links to be aggregated together to form a Link Aggregation
Group. A MAC client can treat Link Aggregation Groups as if they were a single link.

EDS-508A/505A’s Port Trunking feature allows devices to communicate by aggregating up to 2
trunk groups on the EDS-505A and 4 trunk groups on the EDS-508A. If on e of the ports fails, the
other ports in the same trunk group will provide back up and share the traffic automatically.

The Port Trunking Concept

Moxa has developed a proprietary Port Trunking protocol that provides the following benefits:
 Gives you more flexibility in setting up your network connection s , since the bandwidth of a link

can be doubled, tripled, or quadrupled.

 Provides redundancy—if one link is broken, the remaining trunked ports share the traffic within

this trunk group.

 Load sharing—MAC Client traffic may be distributed across multiple links.
 To avoid broadcast storms or loops in your network while configuring a trunk, first disable or

disconnect all ports that you want to add to the trunk or remove from the trunk. After you finish
configuring the trunk, enable or re-connect the ports.

If all ports on both switches are configured as 100BASE-TX and they are operating in full duplex,
the potential bandwidth of the connection will be up to 1 Gbps on an EDS-505A switch and 1.6
Gbps on an EDS-508A switch. This means that users can connect one EDS to another EDS by port
trunking to double, triple, or quadruple the bandwidth of the connection.

EDS-508A/505A Series User’s Manual Featured Functions

3-20

When configuring Port Trunking, note that:

Each EDS-505A can set a maximum of 2 Port Trunking groups (designated Trk1, Trk2). Each
EDS-508A can set a maximum of 4 Port Trunking groups (designated Trk1, Trk2, Trk3, Trk4)

When you activate Port Trunking settings, some advanced functions that you setup with the
original ports will either be set to factory default values, or disabled:

 Communication Redundancy will be set to the factory default
 Traffic Prioritization will be set to the factory default
 Port-based VLAN or 802.1Q VLAN will be set to the factory default
 Multicast Filtering will be set to the factory default
 Rate Limiting will be set to the factory default
 Port Access Control will be set to the factory default
 Email and Relay Warning will be set to the factory default
 Set Device IP will be set to the factory default
 Mirror Port will be set to the factory default

You can setup these features again on your Trunking Port.

Configuring Port Trunking

The Port Trunking Settings page is used to assign ports to a Trunk Group.

Step 1: Select Trk1, Trk2, Trk3, or Trk4 from the Trunk Group drop-down box.
Step 2: Select Static, or LACP from the Trunk Type drop-down box.
Step 3: Under Member Ports and Available Ports, select the specific ports.
Step 4: Use the Up / Down buttons to add/remove designated ports to/from a trunk group.

EDS-508A/505A Series User’s Manual Featured Functions

3-21

Trunk Group (Maximum of 4 trunk groups on E DS-508A and 2 trunk groups on EDS-50 5A )

Setting Description Factory Default

Trk1, Trk2, Trk3, Trk4
on EDS-508A; Trk1,
Trk2 on EDS-505A

Display or designate the Trunk Type and Member
Ports for Trunk Groups 1, 2, 3, 4 (for Trunk Groups
1, 2 on EDS-505A).

Trk1

Trunk Type

Setting Description Factory Default

Static Designated Moxa proprietary trunking protocol Static
LACP

Designated LACP (IEEE 802.3ad, Link
Aggregation Control Protocol)

Static

Available Ports/Member Port

Setting Description Factory Default

Member/Available
Ports

Use Up/Down buttons to add/remove specific ports
from available ports to/from trunk group.

N/A

Check box Check to designate which ports to add or remove. Unchecked
Port Port number N/A
Port description Displays the media type for each module’s port N/A
Name Max. 63 Characters N/A

Speed

Indicates the transmission speed (100M-Full,
100M-Half, 10M-Full, or 10M-Half )

N/A

FDX Flow Control

Indicates if the FDX flow control of this port is
“Enabled” or “Disabled.”

N/A

Up

Add designated ports into trunk group from
available ports.

N/A

Down

Remove designated ports from trunk group t o
available port.

N/A

Trunk Table

Setting Description

Trunk Group Displays the Trunk Type and Trunk Group.
Member Port Display which member ports belong to the trunk group.
Status Success means por t trunking is working properly.

Fail means port trunking is not working properly.
Standby means port trunking is working as a standby port. When there

are more than eight ports trunked as a trunking group, the 9

th

port will

be the standby port.

EDS-508A/505A Series User’s Manual Featured Functions

3-22

Configuring SNMP

The EDS supports SNMP V1/V2c/V3. SNMP V1, and SNMP V2c use a community string match
for authentication, which means that SNMP servers access all objects with read-only or read/write
permissions using the community string public/private (default value). SNMP V3, which requires
you to select an authentication level of MD5 or SHA, is the most secure protocol. You can also
enable data encryption to enhance data security.

SNMP security modes and security levels supported by the EDS are shown in the following table.
Select the security mode and level that will be used to communicate between the SNMP agent and
manager.

Protocol

Version

UI Setting

Authentication

Type

Data

Encryption

Method

V1, V2c
Read
Community

Community
string

No

Use a community string match
for authentication

SNMP V1,
V2c

V1, V2c
Write/Read
Community

Community
string

No

Use a community string match
for authentication

No-Auth No No

Use account with admin or user
to access objects

MD5 or SHA

Authentication
based on MD5
or SHA

No

Provides authentication based on
HMAC-MD5, or HMAC-SHA
algorithms. 8-character
passwords are the minimum
requirement for authentication.

SNMP V3

MD5 or SHA

Authentication
based on MD5
or SHA

Data encryption
key

Provides authentication based on
HMAC-MD5 or HMAC-SHA
algorithms, and data encryption
key. 8-character passwords and a
data encryption key are the
minimum requirements for
authentication and encryption.

These parameters are configured on the SNMP page. A more detailed explanation of each
parameter follows.

EDS-508A/505A Series User’s Manual Featured Functions

3-23

SNMP Read/Write Settings

SNMP Versions

Setting Description Factor y Def ault

V1, V2c, V3, or
V1, V2c, or V3
only

Select the SNMP protocol version used to
manage the switch.

V1, V2c

V1, V2c Read Community

Setting Description Factor y Def ault

V1, V2c Read
Community

Use a community string match with a
maximum of 30 characters for
authentication. The SNMP agent accesses
all objects with read-only permissions
using the community string public.

public

V1, V2c Write/Read Community

Setting Description Factory Default

V1, V2c
Read/Write
Community

Uses a community string match with a
maximum of 30 characters for
authentication. The SNMP servers access
all objects with read/write permissions
using the community string private.

private

For SNMP V3, there are two levels of privileges for different accounts to access the EDS. Admin
privilege allows access, and authorization to read and write the MIB file. User privilege only
allows reading the MIB file, but does not have authorization to write.

Admin Auth. Type (for SNMP V1, V2c, V3, and V3 only)

Setting Description Factor y Def ault

No-Auth

Use admin. account to access objects.
No authentication

No

MD5-Auth

Provide authentication based on the
HMAC-MD5 algorithms. 8-character
passwords are the minimum requirement
for authentication.

No

SHA-Auth

Provide authentication based on the
HMAC-SHA algorithms. 8-character
passwords are the minimum requirement
for authentication.

No

Admin Data Encryption Key (for SNMP V1, V2c, V3, and V3 only)

Setting Description Factor y Def ault

Enable

8-character data encryption key is the
minimum requirement for data encryption
(maximum of 30 characters)

No

Disable No data encryption No

EDS-508A/505A Series User’s Manual Featured Functions

3-24

User Auth. Type (for SNMP V1, V2c, V3 and V3 only)

Setting Description Factor y Def ault

No-Auth

Use admin account or user account to
access objects. No authentication.

No

MD5-Auth

Provides authentication based on the
HMAC-MD5 algorithms. 8-character
passwords are the minimum requirement
for authentication.

No

SHA-Auth

Provides authentication based on the
HMAC-SHA algorithms. 8-character
passwords are the minimum requirement
for authentication.

No

User Data Encryption Key (for SNMP V1, V2c, V3 and V3 only)

Setting Description Factor y Def ault

Enable

8-character data encryption key is the
minimum requirement for data encryption
(maximum of 30 characters)

No

Disable No data encryption No

Trap Settings

SNMP traps allow an SNMP agent to notify the NMS of a significant event. The EDS-508A/505A
supports two SNMP modes, Trap mode and Inform mode.

SNMP Trap Mode

In Trap mode, the SNMP agent sends an SNMPv1 trap PDU to the NMS. No acknowledgment is
sent back from the NMS so the agent has no way of knowing if the trap reached the NMS.

SNMP Inform Mode

SNMPv2 provides an inform mechanism. When an inform message is sent from the SNMP agent
to the NMS, the receiver sends a response to the sender acknowledging receipt of the event. This
behavior is similar to that of the get and set requests. If the SNMP agent doesn’t receive a response
from the NMS for a period of time, the agent will resend the trap to the NMS agent. The maximum
timeout time is 300 secs (default is 1 sec), and the maximum number of retries is 99 times (default
is 1 time). When the SNMP agent receives acknowledgement from the NMS, it will stop resending
the inform messages.

EDS-508A/505A Series User’s Manual Featured Functions

3-25

1

st

Trap Server IP/Name

Setting Description Factor y Def ault

IP or Name

Enter the IP address or name of the 1

st

Trap Server used by your network.

None

1st Trap Community

Setting Description Factor y Def ault

Character String

Use a community string match for
authentication (maximum of 30
characters).

Public

2nd Trap Server IP/Name

Setting Description Factor y Def ault

IP or Name

Enter the IP address or name of the 2

nd

Trap Server used by your network.

None

2nd Trap Community

Setting Description Factor y Def ault

Character String

Use a community string match for
authentication (maximum of 30
characters).

Public

Inform mode select

Setting Description Factor y Def ault

Retries Enter Inform Retry number 1
Time out Enter Inform Timeout window 1

Private MIB information

Switch Object ID

Setting Description Factory Default

8691.7.9 for EDS-508A;

8691.7.8 for EDS-505A

EDS-508A/505A’s enterprise value Fixed

NOTE: The Switch Object ID cannot be changed.

Using Communication Redundancy

Setting up Communication Redundancy on your network helps protect critical links agains t failure,
protects against network loops, and keeps network downtime at a minimum.

EDS-508A/505A Series User’s Manual Featured Functions

3-26

The Communication Redundancy function allows the user to set up redundant loops in the
network to provide a backup data transmission route in the event that a cable is inadvertently
disconnected or damaged. This feature is particularly important for industrial applications, since it
could take several minutes to locate the disconnected or severed cable. For example, if the EDS is
used as a key communications component of a production line, several minutes of downtime could
result in a big loss in production and revenue. The EDS supports three different protocols to
support this communication redundancy function— Rapid Spanning Tree/ Spanning Tree
Protocol (IEEE 802.1W/1D), Turbo Ring, and Turbo Ring V2.

When configuring a redundant ring, all switches on th e same ring must be configured to use the
same redundancy protocol. You cannot mix the “Turbo Ring,” “Turbo Ring V2,” and STP/RSTP
protocols on the same ring. The following table lists the key differences between each feature. Use
this information to evaluate the benefits of each, and then determine which features are most
suitable for your network.

Turbo Ring V2 Turbo Ring STP RSTP
Topology Ring Ring Ring, Mesh Ring, Mesh
Recovery Time < 20 ms < 300 ms Up to 30 sec. Up to 5 sec

NOTE

Most of Moxa’s managed switches now support two proprietary Turbo Ring protocols:

(1) “Turbo Ring” refers to the original version of Moxa’s proprietary redundant ring

protocol, which has a recovery time of under 300 ms.

(2) “Turbo Ring V2” refers to the new generation Turbo Ring, which has a recovery time

of under 20 ms.

In this manual, we use the terminology “Turbo Ring” ring and “Turbo Ring V2” ring to
differentiate between rings configured for one or the other of these protocols.

The Turbo Ring Concept

Moxa developed the proprietary Turbo Ring protocol to optimize communication redundancy and
achieve a faster recovery time on the network.

EDS-508A/505A Series User’s Manual Featured Functions

3-27

The Turbo Ring and Turbo Ring V2 protocols iden tify one switch as the master of the network,
and then automatically block packets from traveling through any of the network’s redundant loops.
In the event that one branch of the ring gets disconnected from the rest of the network, the protocol
automatically readjusts the ring so that the part of the network that was disconnected can
reestablish contact with the rest of the network.

Initial setup of a “Turbo Ring” or “Turbo Ring V2” ring

1. For each switch in the ring, select any two

ports as the redundant ports.

2. Connect redundant ports on neighboring

switches to form the redundant ring.

The user does not need to configure any of the switches as the master to use Turbo Ring or Turbo
Ring V2. If none of the switches in the ring is configured as the master, then the protocol will
automatically assign master status to one of the switches. In fact, the master is only used to
identify which segment in the redundant ring acts as the backup path. In the following subsections,
we explain how the redundant path is selected for rings configured for Turbo Ring, and Turbo
Ring V2.

Determining the Redundant Path of a “Turbo Ring” Ring

In this case, the redundant segment (i.e., the segment that will be blocked during normal operation)
is determined by the number of EDS units that make up the ring, and where the ring master is
located.

EDS-508A/505A Series User’s Manual Featured Functions

3-28

“Turbo Ring” rings with an even number of EDS units

Master

If there are 2N EDS units (an even number) in
the “Turbo Ring” ring, then the backup segment
is one of the two segments connected to the
(N+1)st EDS (i.e., the EDS unit directly
opposite the master).

“Turbo Ring” rings with an odd number of EDS units

Master

Segment N+1

If there are 2N+1 EDS units (an odd number) in
the “Turbo Ring” ring, with EDS units and
segments labeled counterclockwise, then
segment N+1 will serve as the backup path.

For the example shown here, N=1, so that
N+1=2.

Determining the Redundant Path of a “Turbo Ring V2” Ring

EDS-508A/505A Series User’s Manual Featured Functions

3-29

Master

For a “Turbo Ring V2” ring, the backup
segment is the segment connected to the 2nd
redundant port on the master.

See Configuring “Turbo Ring V2” in the

Configuring “Turbo Ring” and “Turbo Ring
V2” section below.

Ring Coupling Configuration

For some systems, it may not be convenient to connect all devices in the system to create one BIG
redundant ring, since some devices could be located in a remote area. For these systems, “Ring
Coupling” can be used to separate the devices into different smaller redundant rings, but in such a
way that they can still communicate with each other.

ATTENTION

In a VLAN environment, the user must set “Redundant Port,” “Coupling Port,” and “Coupling
Control Port” to join all VLANs, since these ports act as the “backbone” to transmit all packets
of different VLANs to different EDS units.

Ring Coupling for a “Turbo Ring” Ring

Switch A: "Coupler"

Switch B

Switch C

Switch D

Main Path

Coupling Port

Backup Path

Coupling
Control Port

To configure the Ring Coupling function for a “Turbo Ring” ring, select two ED S units (e.g.,
Switch A and B in the above figure) in the ring, and another two EDS units in the adjacent ring
(e.g., Switch C and D).

Decide which two ports in each switch are appropriate to be used as coupling ports, and then link
them together. Next, assign one switch (e.g., Switch A) to be the “coupler,” and connect the

EDS-508A/505A Series User’s Manual Featured Functions

3-30

coupler’s coupling control port with Switch B (for this example).
The coupler switch (i.e., Switch A) will monitor switch B through the coupling control port to

determine whether or not the coupling port’s backup path should be recovered.

Ring Coupling for a “Turbo Ring V2” Ring

Switch A

Switch B

Switch D

Coupling Port (Primary)

Switch C

Main Path

Coupling Port (Backup)

Backup Path

Note that the ring coupling settings for a “Turbo Ring V2” ring are different from a “Turbo Ring”
ring. For Turbo Ring V2, Ring Coupling is enabled by configuring the “Coupling Port (Primary)”
on Switch B, and the “Coupling Port (Backup)” on Switch A only. You do not need to set up a
coupling control port, so that a “Turbo Ring V2” ring does not use a coupling control line.

The “Coupling Port (Backup)” on Switch A is used for the backup path, and conn ects directly to
an extra network port on Switch C. The “Coupling Port (Primary)” on Switch B monitors the
status of the main path, and connects directly to an extra network port on Switch D. With ring
coupling established, Switch A can activate the backup path as soon as it detects a problem with
the main path.

ATTENTION

Ring Coupling only needs to be enabled on one of the switches serving as the Ring Coupler. The
Coupler must designate different ports as the two Turbo Ring ports and the coupling port.

NOTE

You do not need to use the same EDS unit for both Ring Coupling and Ring Master.

Dual-Ring Configuration (applies only to “Turbo Ring V2”)

EDS-508A/505A Series User’s Manual Featured Functions

3-31

The “dual-ring” option provides another ring coupling configuration, in which two adjacent rings
share one switch. This type of configuration is ideal for applications that have inherent cabling
difficulties.

Dual-Ring for a “Turbo Ring V2” Ring

Ring A

Master

Master

Ring B

Dual-Homing Configuration (applies only to “Turbo Ring V2”)

The “dual-homing” option uses a single Ethernet switch to connect two networks. The primary
path is the operating connection, and the backup p a th is a back-up connection that is activated in
the event that the primary path connection fails.

Dual-Homing for a “Turbo Ring V2” Ring

Primary
Path

Ring A

Master

Master

Ring B

Backup
Path

Configuring “Turbo Ring” and “Turbo Ring V2”

EDS-508A/505A Series User’s Manual Featured Functions

3-32

Use the Communication Redundancy page to configure select “Turbo Ring” or “Turbo Ring
V2” or “Turbo Chain” Note that configuration pages for these two protocols are different.

Configuring “Turbo Ring”

Explanation of “Current Status” Items

Now Active

Shows which communication protocol is in use: Turbo Ring, Turbo Ring V2, RSTP, or none.

Master/Slave

Indicates whether or not this EDS is the Master of the Turbo Ring. (This field appears only when
selected to operate in Turbo Ring or Turbo Ring V2 mode.)

NOTE

The user does not need to set the master to use Turbo Ring. If no master is set, the Turbo Ring
protocol will assign master status to one of the EDS units in the ring. The master is only used to
determine which segment serves as the backup path.

Redundant Ports Status (1st Port, 2nd Port)
Ring Coupling Ports Status (Coupling Port, Coupling Control Port)

The “Ports Status” indicators show Forwarding for normal transmission, Blocking if this port is
connected to a backup path and the path is blocked, and Link down if there is no connection.

Explanation of “Settings” Items

EDS-508A/505A Series User’s Manual Featured Functions

3-33

Redundancy Protocol

Setting Description Factory Default

Turbo Ring

Select this item to change to the Turbo
Ring configuration page.

Turbo Ring V2

Select this item to change to the Turbo
Ring V2 configuration page.

Turbo Chain

Select this item to change to the Turbo
Chain configuration page

RSTP (IEEE

802.1W/1D)

Select this item to change to the RSTP
configuration page.

None Ring redundancy is not active

None

Set as Master

Setting Description Factory Default

Enabled Select this EDS as Master
Disabled Do not select this EDS as Master

Not checked

Redundant Ports

Setting Description Factory Default

1st Port

Select any port of the EDS to be one
of the redundant ports.

EDS-505A

: port 4

EDS-508A

: port 7

2nd Port

Select any port of the EDS to be one
of the redundant ports.

EDS-505A

: port 5

EDS-508A

: port 8

Enable Ring Coupling

Setting Description Factory Default

Enable Select this EDS as Coupler
Disable Do not select this EDS as Coupler

Not checked

Coupling Port

Setting Description Factory Default

Coupling Port

Select any port of the EDS to be the
coupling port

EDS-505A

: port 2

EDS-508A

: port 5

Coupling Control Port

Setting Description Factory Default

Coupling Control Port

Select any port of the EDS to be the
coupling control port

EDS-505A

: port 3

EDS-508A

: port 6

Configuring “Turbo Ring V2”

EDS-508A/505A Series User’s Manual Featured Functions

3-34

NOTE

When using the Dual-Ring architecture, users must configure settings for both Ring 1 and Ring 2.
In this case, the status of both rings will appear under “Current Status.”

Explanation of “Current Status” Items

Now Active

Shows which communication protocol is in use: Turbo Ring, Turbo Ring V2, Turbo Chain,
RSTP, or none.

Ring 1/2—Status

Shows Healthy if the ring is operating normally, and shows Break if the ring’s backup link is
active.

Ring 1/2—Master/Slave

Indicates whether or not this EDS is the Master of the Turbo Ring. (This field appears only when
selected to operate in Turbo Ring or Turbo Ring V2 mode.)

NOTE

The user does not need to set the master to use Turbo Ring. If no master is set, the Turbo Ring
protocol will assign master status to one of the EDS units in the ring. The master is only used to
determine which segment serves as the backup path.

Ring 1/2—1st Ring Port Status

EDS-508A/505A Series User’s Manual Featured Functions

3-35

Ring 1/2—2nd Ring Port Status

The “Ports Status” indicators show Forwarding for normal transmission, Blocking if this port is
connected to a backup path and the path is blocked, and Link down if there is no connection.

Coupling—Mode
Indicates either None, Dual Homing, or Ring Coupling.

Coupling—Coupling Port status

Indicates either Primary, or Backup.

Explanation of “Settings” Items

Redundancy Protocol

Setting Description Factory Defau l t

Turbo Ring

Select this item to change to the
Turbo Ring configuration page.

Turbo Ring V2

Select this item to change to the
Turbo Ring V2 configuration page.

Turbo Chain

Select this item to change to the
Turbo Chain configuration page

RSTP (IEEE

802.1W/1D)

Select this item to change to the
RSTP configuration page.

None Ring redundancy is not active

None

Enable Ring 1

Setting Description Factory Defau l t

Enabled Enable the Ring 1 settings
Disabled Disable the Ring 1 settings

Not checked

Enable Ring 2*

Setting Description Factory Defau l t

Enabled Enable the Ring 2 settings
Disabled Disable the Ring 2 settings

Not checked

*You should enable both Ring 1 and Ring 2 when using the Dual-Ring architecture.

Set as Master

Setting Description Factory Defau l t

Enabled Select this EDS as Master
Disabled Do not select this EDS as Master

Not checked

Redundant Ports

Setting Description Factory Defau l t

1st Port

Select any port of the EDS to be
one of the redundant ports.

EDS-505A

: port 4

EDS-508A

: port 7

2nd Port

Select any port of the EDS to be
one of the redundant ports.

EDS-505A

: port 5

EDS-508A

: port 8

Enable Ring Coupling

EDS-508A/505A Series User’s Manual Featured Functions

3-36

Setting Description Factory Defau l t

Enable Select this EDS as Coupler
Disable Do not select this EDS as Coupler

Not checked

Coupling Mode

Setting Description Factory Default

Dual Homing

Select this item to change to the
Dual Homing configuration page

EDS-508A
Primary Port: port 5
Backup Port: port 6
EDS-505A
Primary Port: port 2
Backup Port: port 3

Ring Coupling
(backup)

Select this item to change to the
Ring Coupling (backup)
configuration page

EDS-508A

: Port 5

EDS-505A

: Port 2

Ring Coupling
(primary)

Select this item to change to the
Ring Coupling (primary)
configuration page

EDS-508A

: Port 5

EDS-505A

: Port 2

Primary/Backup Port

Setting Description Factory Defau l t

Primary Port

Select any port of the EDS to be the
primary port.

EDS-505A

: port 2

EDS-508A

: port 5

Backup Port

Select any port of the EDS to be the
backup port.

EDS-505A

: port 3

EDS-508A

: port 6

NOTE

The Turbo Ring DIP Switches located on the
EDS-508A/505A’s outer casing can be used to
configure the EDS’s Turbo Ring protocol s. (For
details on how to do this, refer to “Configuring Basic
Settings—Turbo Ring DIP Switch” section in this
manual.)

If you use the web interface, console interface, or
Telnet interface to enable the Turbo Ring DIP
Switches, and then set DIP Switch 4 on the switch’s
outer casing to the “ON” position, you will not be able
to use the web interface, console interface, or Telnet
interface to change the status of the DIP Switch. In
this case, the Communication Redundancy settings
will be “grayed out” in the web browser as shown in
the following figure:

The Turbo Chain Concept

EDS-508A/505A Series User’s Manual Featured Functions

3-37

Moxa’s Turbo Chain is an advanced software-technology that gives network administrators the
flexibility of constructing any type of redundant network topology. When using the “chain”
concept, you first connect the Ethernet switches in a chain and then simply link the two ends of the
chain to an Ethernet network, as illustrated in the following figure.

Turbo Chain can be used on industrial networks that have a complex topology. If the industrial
network uses a multi-ring architecture, Turbo Chain can be used to create flexible and scalable
topologies with a fast media-recovery time.

Setup Turbo Chain

1. Select the Head switch, Tail switch, and Member switches.

2. Configure one port as the Head port and one port as the Member port in the Head switch,

configure one port as the Tail port and one port as the Member port in the Tail switch, and
configure two ports as Member ports in each of the Member switches.

3. Connect the Head switch, Tail switch, and Member switches as shown in the diagram.

The path connecting to the Head port is the main path, and the path connecting to the Tail port is
the back up path of the Turbo Chain. Under normal conditions, packets are transmitted through the
Head Port to the LAN Network. If any Turbo Chain path is disconnected, the Tail Port will be
activated to continue packet transmission.

Configuring “Turbo Chain”

EDS-508A/505A Series User’s Manual Featured Functions

3-38

Head Switch Configuration

Member Switch Configuration

Tail Switch Configuration

Explanation of “Current Status” Items

Now Active

EDS-508A/505A Series User’s Manual Featured Functions

3-39

Shows which communication protocol is in use: Turbo Ring, Turbo Ring V2, RSTP, Turbo
Chain or None.

The “Ports Status” indicators show Forwarding for normal transmission, Blocked if this port is
connected to the Tail port as a backup path and the path is blocked, and Link down if there is no
connection.

Explanation of “Settings” Items

Redundancy Protocol

Setting Description Factory Default

Turbo Ring

Select this item to change to the Turbo
Ring configuration page.

Turbo Ring V2

Select this item to change to the Turbo
Ring V2 configuration page.

Turbo Chain

Select this item to change to the Turbo
Chain configuration page

RSTP (IEEE

802.1W/1D)

Select this item to change to the RSTP
configuration page.

None Ring redundancy is not active

None

Role

Setting Description Factory Default

Head Select this EDS as Head Switch
Member Select this EDS as Member Switch
Tail Select this EDS as Tail Switch

Member

Head Role

Setting Description Factory Default

Head Port

Select any port of the EDS to be the head
port.

EDS-505A: port 4
EDS-508A: port 7

Member Port

Select any port of the EDS to be the
member port.

EDS-505A: port 5
EDS-508A: port 8

Member Role

Setting Description Factory Default

1st Member port

Select any port of the EDS to be the 1

st

member port

EDS-505A: port 4
EDS-508A: port 7

2nd Member port

Select any port of the EDS to be the 2

nd

member port

EDS-505A: port 5
EDS-508A: port 8

Tail Role

EDS-508A/505A Series User’s Manual Featured Functions

3-40

Setting Description Factory Default

Tail Port

Select any port of the EDS to be the tail
port.

EDS-505A: port 4
EDS-508A: port 7

Member Port

Select any port of the EDS to be the
member port.

EDS-505A: port 5
EDS-508A: port 8

The STP/RSTP Concept

Spanning Tree Protocol (STP) was designed to help reduce link failures in a network, and provide
protection from loops. Networks that have a complicated architecture are prone to broadcast
storms caused by unintended loops in the network. The EDS’s STP feature is disabled by default.
To be completely effective, you must enable RSTP/STP on every EDS connected to your network.

Rapid Spanning Tree Protocol (RSTP) implements the Spanning Tree Algorithm and Protocol
defined by IEEE Std 802.1w-2001. RSTP provides the following benefits:

 The topology of a bridged network will be determined much more quickly compared to STP.
 RSTP is backward compatible with STP, making it relatively easy to deploy. For example:

 Defaults to sending 802.1D style BPDUs if packets with this format are received.
 STP (802.1D) and RSTP (802.1w) can operate on different ports of the same EDS. This

feature is particularly helpful when the EDS’s ports connect to older equipment, such as
legacy switches.

You get essentially the same functionality with RSTP and STP. To see how the two systems differ,
see the Differences between RSTP and STP section in this chapter.

NOTE

The STP protocol is part of the IEEE Std 802.1D, 1998 Edition bridge specification. The
following explanation uses bridge instead of switch.

What is STP?

EDS-508A/505A Series User’s Manual Featured Functions

3-41

STP (802.1D) is a bridge-based system that is used to implement parallel paths for network traffic.
STP uses a loop-detection process to:

 Locate and then disable less efficient paths (i.e., paths that have a lower bandwidth).
 Enable one of the less efficient paths if the most efficient path fails.

The figure below shows a network made up of three LANs separated by three bridges. Each
segment uses at most two paths to communicate with the other segments. Since this configuration
can give rise to loops, the network will overload if STP is NOT enabled.

If STP is enabled, it will detect duplicate paths and prevent, or block, one of them from forwarding
traffic. In the following example, STP determined that traffic from LAN segment 2 to LAN
segment 1 should flow through Bridges C and A because this path has a greater bandwidth and is
therefore more efficient.

Bridge B

Bridge C

LAN 1

LAN 2

LAN 3

Bridge A

Bridge B

Bridge C

LAN 1

LAN 2

LAN 3

Bridge A

EDS-508A/505A Series User’s Manual Featured Functions

3-42

What happens if a link failure is detected? As shown in next figure, the STP process reconfigures
the network so that traffic from LAN segment 2 flows through Bridge B.

STP will determine which path between each bridged segment is most efficient, and then assigns a
specific reference point on the network. When the most efficient path has been identified, the other
paths are blocked. In the previous 3 figures, STP first determined that the path through Bridge C
was the most efficient, and as a result, blocked the path through Bridge B. After the failure of
Bridge C, STP re-evaluated the situation and opened the path through Bridge B.

How STP Works

When enabled, STP determines the most appropriate path for traffic through a network. The way it
does this is outlined in the sections below.

STP Requirements

Before STP can configure the network, the system must satisfy the following requirements:
 Communication between all the bridges. This communication is carried out using Bridge

Protocol Data Units (BPDUs), which are transmitted in packets with a known multicast address.

 Each bridge must have a Bridge Identifier that specifies which bridge acts as the central

reference point, or Root Bridge, for the STP system—bridges with a lower Bridge Identifier are
more likely to be designated as the Root Bridge. The Bridge Identifier is calculated using the
MAC address of the bridge and a priority defined for the bridge. The default priority of the EDS
is 32768.

 Each port has a cost that specifies the efficiency of each link. The efficiency cost is usually

determined by the bandwidth of the link, with less efficient links assigned a higher cost. The
following table shows the default port costs for a switch:

Port Speed Path Cost 802.1D,

1998 Edition

Path Cost

802.1w-2001

10 Mbps 100 2,000,000
100 Mbps 19 200,000
1000 Mbps 4 20,000

Bridge B

Bridge C

LAN 1

LAN 2

LAN 3

Bridge A

EDS-508A/505A Series User’s Manual Featured Functions

3-43

STP Calculation

The first step of the STP process is to perform calculations. During this stage, each bridge on the
network transmits BPDUs. The following items will be calculated:

 Which bridge should be the Root Bridge. The Root Bridge is the central reference point from

which the network is configured.

 The Root Path Costs for each bridge. This is the cost of the paths from each bridge to the Root

Bridge.

 The identity of each bridge’s Root Port. The Root Port is the port on the bridge that connects to

the Root Bridge via the most efficient path. In other words, the port connected to the Root
Bridge via the path with the lowest Root Path Cost. The Root Bridge, however, does not have a
Root Port.

 The identity of the Designated Bridge for each LAN segment. The Designated Bridge is the

bridge with the lowest Root Path Cost from that segment. If several bridges have the same Root
Path Cost, the one with the lowest Bridge Identifier becomes the Designated Bridge. Traffic
transmitted in the direction of the Root Bridge will flow through the Designated Bridge. The
port on this bridge that connects to the segment is called the Designated Bridge Port.

STP Configuration

After all the bridges on the network agree on the identity of the Root Bridge, and all other relevant
parameters have been established, each bridge is configured to forward traffic only between its
Root Port and the Designated Bridge Ports for the respective network segments. All other ports are
blocked, which means that they will not be allowed to receive or forward traffic.

STP Reconfiguration

Once the network topology has stabilized, each bridge listens for Hello BPDUs transmitted from
the Root Bridge at regular intervals. If a bridge does not receive a Hello BPDU after a certain
interval (the Max Age time), the bridge assumes that the Root Bridge, or a link between itself and
the Root Bridge, has gone down. This will trigger the bridge to reconfigure the network to account
for the change. If you have configured an SNMP trap destination, when the topology of your
network changes, the first bridge to detect the change sends out an SNMP trap.

Differences between RSTP and STP

RSTP is similar to STP, but includes additional information in the BPDUs that allow each bridge
to confirm that it has taken action to prevent loops from forming when it decides to enab le a link
to a neighboring bridge. Adjacent bridges connected via point-to-point links will be able to enable
a link without waiting to ensure that all other bridges in the network have had time to react to the
change. The main benefit of RSTP is that the configuration decision is made locally rather than
network-wide, allowing RSTP to carry out automatic configuration and restore a link faster than
STP.

EDS-508A/505A Series User’s Manual Featured Functions

3-44

STP Example

The LAN shown in the following figure has three segments, with adjacent segments connected
using two possible links. The various STP factors, such as Cost, Root Port, Designated Bridge Port,
and Blocked Port are shown in the figure.

Bridge A

LAN Segment 3

LAN Segment 2

LAN Segment 1

Port 2
(Root Bridge)

Port 1
(Designated
Bridge Port)

Bridge B

Port 2
(Designated
Bridge Port)

Port 1
(Root Port)

Cost =100

Bridge X

Port 2
(Blocked Port)

Port 1
(Root Port)

Cost =100

Bridge C

Port 2
(Designated
Bridge Port)

Port 1
(Root Port)

Cost =100

Bridge Y

Port 2
(Blocked Port)

Port 1
(Root Port)

Cost =200

 Bridge A has been selected as the Root Bridge, since it was determined to have the lowest

Bridge Identifier on the network.

 Since Bridge A is the Root Bridge, it is also the Designated Bridge for LAN segment 1. Port 1

on Bridge A is selected as the Designated Bridge Port for LAN Segment 1.

 Ports 1 of Bridges B, C, X, and Y are all Root Ports sine they are nearest to the Root Bridge,

and therefore have the most efficient path.

 Bridges B and X offer the same Root Path Cost for LAN segment 2. However, Bridge B was

selected as the Designated Bridge for that segment since it has a lower Bridge Identifier. Port 2
on Bridge B is selected as the Designated Bridge Port for LAN Segment 2.

 Bridge C is the Designated Bridge for LAN segment 3, because it has the lowest Root Path Cost

for LAN Segment 3:

 The route through Bridges C and B costs 200 (C to B=100, B to A=100)
 The route through Bridges Y and B costs 300 (Y to B=200, B to A=100)

 The Designated Bridge Port for LAN Segment 3 is Port 2 on Bridge C.

EDS-508A/505A Series User’s Manual Featured Functions

3-45

Using STP on a Network with Multiple VLANs

IEEE Std 802.1D, 1998 Edition, does not take into account VLANs when calculating STP
information—the calculations only depend on the physical connections. Consequently, some
network configurations will result in VLANs being subdivided into a number of isolated sectio ns
by the STP system. You must ensure that every VLAN configuration on your network takes into
account the expected STP topology and alternative topologies that may result from link failures.

The following figure shows an example of a network that con tains VL ANs 1 and 2. The VLANs
are connected using the 802.1Q-tagged link between Switch B and Switch C. By default, this link
has a port cost of 100 and is automatically blocked because the other Switch-to-Switch
connections have a port cost of 36 (18+18). This m eans tha t both VLANs are now
subdivided—VLAN 1 on Switch units A and B cannot communicate with VLAN 1 on Switch C,
and VLAN 2 on Switch units A and C cannot communicate with VLAN 2 on Switch B.

Block

Switch A

Switch B Switch C

802.1Q tagged,
10BaseTx
half-duplex Link
carries VLAN1, 2
(path cost = 100)

100BaseTX
full-duplex Link;
only carries VLAN2
(path cost = 18)

100BaseTX
full-duplex Link;
only carries VLAN1
(path cost = 18)

VLAN1
VLAN2

VLAN1
VLAN2

VLAN1
VLAN2

To avoid subdividing VLANs, all inter-switch connections should be made members of all
available 802.1Q VLANs. This will ensure connectivity at all times. For example, the connections
between Switches A and B, and between Switches A and C should be 802.1Q tagged and carrying
VLANs 1 and 2 to ensure connectivity.

See the “Configuring Virtual LANs” section for more information about VLAN Tagging.

EDS-508A/505A Series User’s Manual Featured Functions

3-46

Configuring STP/RSTP

The following figures indicate which Spanning Tree Prot o col pa rameters can be configured. A
more detailed explanation of each parameter follows.

At the top of this page, the user can check the “Current Status” of this function. For RSTP, you
will see:

Now Active:

This will show which communication protocol is being used—Turbo Ring, RSTP, or neither.

Root/Not Root

This field will appear only when selected to operate in RSTP mode. It indicates whether or not this
EDS is the Root of the Spanning Tree (the root is determined automatically).

At the bottom of this page, the user can configure the “Settings” of this function. For RSTP, you
can configure:

Protocol of Redundancy

Setting Description Factory Default

Turbo Ring Select this item to change to the Turbo Ring

configuration page.

None

RSTP (IEEE 802.1W/1D) Select this item to change to the RSTP

configuration page.

None

Bridge priority

Setting Description Factory Default

Numerical value selected
by user

Increase this device’s bridge priority by
selecting a lower number. A device with a
higher bridge priority has a greater chance of
being established as the root of the Spanning
Tree topology.

32768

EDS-508A/505A Series User’s Manual Featured Functions

3-47

Forwarding Delay

Setting Description Factory Default

Numerical value input by
user

The amount of time this device waits before
checking to see if it should change to a
different state.

15 (sec.)

Hello time (sec.)

Setting Description Factory Default

Numerical value input by
user

The root of the Spanning Tree topology
periodically sends out a “hello” message to
other devices on the network to check if the
topology is healthy. The “hello time” is the
amount of time the root waits between sending
hello messages.

2

Max. Age (sec.)

Setting Description Factory Default

Numerical value input by
user

If this device is not the root, and it has not
received a hello message from the root in an
amount of time equal to “Max. Age,” then this
device will reconfigure itself as a root. Once
two or more devices on the network are
recognized as a root, the devices will
renegotiate to set up a new Spanning Tree
topology.

20

Enable STP per Port

Setting Description Factory Default

Enable/Disable Select to enable the port as a node on the

Spanning Tree topology.

Disabled

NOTE

We suggest not enabling the Spanning Tree Protocol once the port is connected to a device (PLC,
RTU, etc.) as opposed to network equipment. The reason is that it will cause unnecessary
negotiation.

Port Priority

Setting Description Factory Default

Numerical value selected
by user

Increase this port’s priority as a node on the
Spanning Tree topology by entering a lower
number.

128

Port Cost

Setting Description Factory Default

Numerical value input by
user

Input a higher cost to indicate that this port is
less suitable as a node for the Spanning Tree
topology.

200000

Port Status

Indicates the current Spanning Tree status of this port. “Forwarding” for normal transmission, or
“Blocking” to block transmission.

EDS-508A/505A Series User’s Manual Featured Functions

3-48

Configuration Limits of RSTP/STP

The Spanning Tree Algorithm places limits on three of the configuration items described
previously:

[Eq. 1]: 1 sec ≦ Hello Time ≦ 10 sec
[Eq. 2]: 6 sec ≦ Max. Age ≦ 40 sec
[Eq. 3]: 4 sec ≦ Forwarding Delay ≦ 30 sec

These three variables are further restricted by the following two inequalities:
[Eq. 4]: 2 * (Hello Time + 1 sec) ≦ Max. Age ≦ 2 * (Forwarding Delay – 1 sec)

The EDS’s firmware will alert you immediately if any of these restrictions are violated. For
example, setting

Hello Time = 5 sec, Max. Age = 20 sec, and Forwarding Delay = 4 sec does not violate Eqs. 1
through 3, but does violate Eq. 4, since in this case,

2 * (Hello Time + 1 sec) = 12 sec, and 2 * (Forwarding Delay – 1 sec) = 6 sec.
You can remedy the situation in many ways. One solution is simply to increase the Forwarding

Delay value to at least 11 sec.
HINT: Perform the following steps to avoid guessing:
Step 1: Assign a value to “Hello Time” and then calculate the left most part of Eq. 4 to get the

lower limit of “Max. Age.”
Step 2: Assign a value to “Forwarding Delay” and then calculate the right most part of Eq. 4 to get

the upper limit for “Max. Age.”
Step 3: Assign a value to “Forwarding Delay” that satisfies the conditions in Eq. 3 and Eq. 4.

Using Traffic Prioritization

The EDS’s traffic prioritization capability provides Quality of Service (QoS) to your network by
making data delivery more reliable. You can prioritize traffic on your network to ensure that high
priority data is transmitted with minimum delay. Traffic can be controlled by a set of rules to
obtain the required Quality of Service for your network. The rules define different types of traffic
and specify how each type should be treated as it passes through the switch. The EDS can inspect
both IEEE 802.1p/1Q layer 2 CoS tags, and even layer 3 TOS information to provide consistent
classification of the entire network. The EDS’s QoS capability improves the performance and
determinism of industrial networks for mission critical applications.

The Traffic Prioritization Concept

What is Traffic Prioritization?

Traffic prioritization allows you to prioritize data so that time-sensitive and system-critical data
can be transferred smoothly and with minimal delay over a network. The benefits of using traffic
prioritization are:

 Improve network performance by controlling a wide variety of traffic and managing congestion.
 Assign priorities to different categories of traffic. For example, set higher priorities for

time-critical or business-critical applications.

 Provide predictable throughput f or multimedia applications, such as video conferencing or

voice over IP, and minimize traffic delay and jitter.

 Improve network performance as the amount of traffic grows. This will save cost by reducing

the need to keep adding bandwidth to the network.

EDS-508A/505A Series User’s Manual Featured Functions

3-49

How Traffic Prioritization Works

Traffic prioritization uses the four traffic queues that are present in your EDS to ensure that high
priority traffic is forwarded on a different queue from lower priority traffic. This is what provides
Quality of Service (QoS) to your network.

EDS traffic prioritization depends on two industry-standard methods:

 IEEE 802.1D—a layer 2 marking scheme.
 Differentiated Services (DiffServ)—a layer 3 marking scheme.

IEEE 802.1D Traffic Marking

The IEEE Std 802.1D, 1998 Edition marking scheme, which is an enhancement to IEEE Std

802.1D, enables Quality of Service on the LAN. Traffic service levels are defined in the IEEE

802.1Q 4-byte tag, which is used to carry VLAN identification as well as IEEE 802.1p priority
information. The 4-byte tag immediately follows the destination MAC address and So urce MAC
address.

The IEEE Std 802.1D, 1998 Edition priority marking scheme assigns an IEEE 802.1p priority
level between 0 and 7 to each frame. This determines the level of service that that type of traffic
should receive. Refer to the table below for an example of how different traffic types can be
mapped to the eight IEEE 802.1p priority levels.

IEEE 802.1p Priority Level IEEE 802.1D Traffic Type

0 Best Effort (default)
1 Background
2 Standard (spare)
3 Excellent Effort (business critical)
4 Controlled Load (streaming multimedia)
5 Video (interactive media); less than 100 milliseconds of

latency and jitter

6 Voice (interactive voice); less than 10 milliseconds of

latency and jitter

7 Network Control Reserved traffic

Even though the IEEE 802.1D standard is the most widely used prioritization scheme in the LAN
environment, it still has some restrictions:

 It requires an additional 4-byte tag in the frame, which is normally optional in Ethernet

networks. Without this tag, the scheme cannot work.

 The tag is part of the IEEE 802.1Q header, so to implement QoS at layer 2, the entire network

must implement IEEE 802.1Q VLAN tagging.

It is only supported on a LAN and not routed across WAN links, since the IEEE 802.1Q tags are
removed when the packets pass through a router.

Differentiated Services (DiffServ) Traffic Marking

DiffServ is a Layer 3 marking scheme that uses the DiffServ Code Point (DSCP) field in the IP
header to store the packet priority information. DSCP is an advanced intelligent method of traffic
marking as you can choose how your network prioritizes different types of traffic. DSCP uses 64
values that map to user-defined service levels, allowing you to establish more control over
network traffic.

EDS-508A/505A Series User’s Manual Featured Functions

3-50

Advantages of DiffServ over IEEE 802.1D are:
 Configure how you want your switch to treat selected app lications and types of traffic by

assigning various grades of network service to them.

 No extra tags are required in the packet.
 DSCP uses the I P header of a packet and ther efore priority is preserved across the Internet.
 DSCP is backward compatible with IPV4 TOS, which allows operation with existing devices

that use a layer 3 TOS enabled prioritization scheme.

Traffic Prioritization

The EDS classifies traffic based on layer 2 of the OSI 7 layer model, and the switch prioritizes
received traffic according to the priority information define d in the received packet. Incoming
traffic is classified based upon the IEEE 802.1D frame and is assigned to the appropriate priority
queue based on the IEEE 802.1p service level value defined in that packet. Service level markings
(values) are defined in the IEEE 802.1Q 4-byte tag, and consequently traffic will only contain

802.1p priority markings if the network is configured with VLANs and VLAN tagging. The traffic
flow through the switch is as follows:

1. A packet received by the EDS may or may not have an 802.1p tag associated with it. If it does

not, then it is given a default 802.1p tag (which is usually 0). Alternatively, the packet may be
marked with a new 802.1p value, which will result in all knowledge of the old 802.1p tag
being lost.

2. As the 802.1p priority levels are fixed to the traffic queues, the packet will be placed in the

appropriate priority queue, ready for transmission through the appropriate egress port. When
the packet reaches the head of its queue and is about to be transmitted, the device determines
whether or not the egress port is tagged for that VLAN. If it is, then the new 802.1p tag is
used in the extended 802.1D header.

The EDS will check a packet received at the ingress port for IEEE 802.1D traffic classification,
and then prioritize it based upon the IEEE 802.1p value (service levels) in that tag. It is this 802.1p
value that determines to which traffic queue the packet is mapped.

Traffic Queues

The EDS hardware has multiple traffic queues that allow packet prioritization to occur. Higher
priority traffic can pass through the EDS without being delayed by lower priority traffic. As each
packet arrives in the EDS, it passes through any ingress processing (which includes classification,
marking/re-marking), and is then sorted into the appropriate queue. The switch then forwards
packets from each queue.

The EDS supports two different queuing mechanisms:
 Weight Fair: This method services all the traffic queues, giving priority to the higher priority

queues. Under most circumstances, this method gives high priority precedence over
low-priority, but in the event that high-priority traffic exceeds the link capacity, lower priority
traffic is not blocked.

 Strict: This method services high traffic queues first; low priority queues are delayed until no

more high priority data needs to be sent. This method always gives precedence to high priority
over low-priority.

EDS-508A/505A Series User’s Manual Featured Functions

3-51

Configuring Traffic Prioritization

Quality of Service (QoS) provides a traffic prioritization capability to ensure that important data is
delivered consistently and predictably. The EDS can inspect IEEE 802.1p/1Q layer 2 CoS tags,
and even layer 3 TOS information, to provide a consistent classification of the entire network. The
EDS’s QoS capability improves your industrial network’s performance and determinism for
mission critical applications.

QoS Classification

The EDS supports inspection of layer 3 TOS and/or layer 2 CoS tag information to determine how
to classify traffic packets.

Queuing Mechanism

Setting Description Factory Default

Weighted Fair The EDS has 4 priority queues. In the weighted fair

scheme, an 8, 4, 2, 1 weighting is applied to the four
priorities. This approach prevents the lower priority
frames from being starved of opportunit y for
transmission with only a slight delay to the higher
priority frames.

Strict In the Strict-priority scheme, all top-priority frames

egress a port until that priority’s queue is empty, and
then the next lower priority queue’s frames egress. This
approach can cause the lower priorities to be starved of
opportunity for transmitting any frames but ensures all
high priority frames to egress the switch as soon as
possible.

Weight Fair

Port Highest Priority

Setting Description Factory Default

Low/Normal/
Medium/High

Set the Port Default Priority of the ingress frames to
different priority queues. If the received packets are not
equipped with any tag information (COS, TOS) the

Normal

EDS-508A/505A Series User’s Manual Featured Functions

3-52

default port priority will take effect.

Inspect TOS

Setting Description Factory Default

Enable/Disable Select the option to enable the EDS to inspect the Type

of Service (TOS) bits in IPV4 frame to determine the
priority of each frame.

Enable

Inspect COS

Setting Description Factory Defau l t

Enable/Disable Select the option to enable the EDS to inspect the 802.1p

COS tag in the MAC frame to determine the priority of
each frame.

Enable

NOTE

The priority of an ingress frame is determined in order by:

1. Inspect TOS

2. Inspect CoS

3. Port Highest Priority

NOTE

The designer can enable these classifications individually or in combination. For instance, if a
‘hot,’ higher priority port is required for a network design, “Inspect TOS” and “Inspect CoS” can
be disabled. This setting leaves only port default priority active, which results in all ingress
frames being assigned the same priority on that port.

CoS Mapping

Setting Description Factory

Low/Normal/
Medium/High

Set the mapping table of different CoS values to 4
different egress queues.

0: Low
1: Low
2: Normal
3: Normal
4: Medium

EDS-508A/505A Series User’s Manual Featured Functions

3-53

5: Medium
6: High
7: High

TOS/DiffServ Mapping

Setting Description Factory Default

Low/Normal/
Medium/High

Set the mapping table of different TOS values to 4
different egress queues.

1 to 16: Low
17 to 32: Normal
33 to 48: Medium
49 to 64: High

Using Virtual LAN

Setting up Virtual LANs (VLANs) on your EDS increases the efficiency of your network by
dividing the LAN into logical segments, as opposed to physical segments. In general, VLANs are
easier to manage.

The Virtual LAN (VLAN) Concept

What is a VLAN?

A VLAN is a group of devices that can be located anywhere on a network, but which
communicate as if they are on the same physical segment. With VLANs, you can segment your
network without being restricted by physical connections—a limitation of traditional network
design. As an example, with VLANs you can segment your network according to:

 Departmental groups—You could have one VLAN for the Marketing department, another for

the Finance department, and another for the Development department.

 Hierarchical groups—You could have one VLAN for directors, another for managers, and

another for general staff.

 Usage groups—You could have one VLAN for e-mail users, and another for multimedia users.

EDS-508A/505A Series User’s Manual Featured Functions

3-54

Benefits of VLANs

The main benefit of VLANs is that they provide a network segmentation system that is far more
flexible than traditional networks. Using VLANs also provides you with three other benefits:

 VLANs ease the relocation of devices on networks: With traditional networks, net w or k

administrators spend most of their time dealing with moves and changes. If users move to a
different subnetwork, the addresses of each host must be updated manually. With a VLAN
setup, if a host on VLAN Marketing, for example, is moved to a port in another part of the
network, and retains its original subnet membership, you only need to specify that the new
port is on VLAN Marketing. You do not need to carry out any re-cabling.

 VLANs provide extra security: Devices within each VLAN can only communicate with other

devices on the same VLAN. If a device on VLAN Marketing needs to communicate with
devices on VLAN Finance, the traffic must pass through a routing device or Layer 3 switch.

 VLANs help control traffic: With traditional networks, congestion can be caused by broadcast

traffic that is directed to all network devices, regardless of whether or not they need it. VLANs
increase the efficiency of your network because each VLAN can be set up to contain only
those devices that need to communicate with each other.

VLANs and Moxa EtherDevice Switch

Your EDS provides support for VLANs using IEEE Std 802.1Q-1998. This standard allows traffic
from multiple VLANs to be carried across one physical link. The IEEE Std 802.1Q-1998 standard
allows each port on your EDS to be placed in:

 Any one VLAN defined on the EDS.
 Several VLANs at the same time using 802.1Q tagging.

The standard requires that you define the 802.1Q VLAN ID for each VLAN on your EDS before
the switch can use it to forward traffic:

1 2

3 4

5 6

7 8

1 2

3 4

5 6

7 8

Switch A

Switch B

Backbone connects multiple switches

Department 1
VLAN 1

Department 2
VLAN 2

Department 3
VLAN 3

EDS-508A/505A Series User’s Manual Featured Functions

3-55

Managing a VLAN

A new or initialized EDS contains a single VLAN—the Default VLAN. This VLAN has the
following definition:

 VLAN Name—Management VLAN
 802.1Q VLAN ID—1 (if tagging is required)

All the ports are initially placed on this VLAN, and it is the only VLAN that allows you to access
the management software of the EDS over the network.

Communication between VLANs

If devices connected to a VLAN need to communicate to devices on a different VLAN, a router or
Layer 3 switching device with connections to both VLANs needs to be installed. Communication
between VLANs can only take place if they are all connected to a routing or Layer 3 switching
device.

VLANs: Tagged and Untagged Membership

The EDS supports 802.1Q VLAN tagging, a system that allows traffic for multiple VLANs to be
carried on a single physical (backbone, trunk) link. When setting up VLANs you need to
understand when to use untagged and tagged membership of VLANs. Simply put, if a port is on a
single VLAN it can be an untagged member, but if the port needs to be a member of multiple
VLANs, tagged membership must be defined.

A typical host (e.g., clients) will be untagged members of one VLAN, defined as “Access Port” in
the EDS, while inter-switch connections will be tagged members of all VLANs, defined as “Trunk
Port” in the EDS.

The IEEE Std 802.1Q-1998 defines how VLANs ope rate wi thi n an open packet -switched network.
An 802.1Q compliant packet carries additional information that allows a switch to determine
which VLAN the port belongs. If a frame is carrying the additional information, it is known as a
tagged frame.

To carry multiple VLANs across a single physical (backbone, trunk) link, each packet must be
tagged with a VLAN identifier so that the switches can identify which packets belong to which
VLAN. To communicate between VLANs, a router must be used.

The EDS supports two types of VLAN port settings:
 Access Port: The port connects to a single device that is not tagged. The user must define the

default port PVID that determines to which VLAN the device belongs. Once the ingress packet
of this Access Port egresses to another Trunk Port (the port needs all packets to carry tag
information), the EDS will insert this PVID into this packet to help the next 802.1Q VLAN
switch recognize it.

 Trunk Port: The port connects to a LAN that consists of untagged devices/tagged devices

and/or switches and hubs. In general, the traffic of the Trunk Port must have a Tag. Users can
also assign PVID to a Trunk Port. The untagged packet on the Trunk Port will be assigned the
port default PVID as its VID.

EDS-508A/505A Series User’s Manual Featured Functions

3-56

The following section illustrates how to use these ports to set up different applications.

Sample Applications of VLANs using the EDS-508A/505A

Port 3 (Trunk Port, PVID 1)

VLAN 5 Untagged Device

VLAN 3 Untagged
Device

VLAN 4 Untagged
Device

VLAN 5 Untagged Device

VLAN 2 Untagged
Device

VLAN 4 Tagged Device, VID 4

VLAN 3 Tagged Device, VID 3

VLAN 2 Untagged
Device

VLAN 2 Untagged
Device

Device A Switch A Switch B

Device C

Device B

Device D

Device E

Device F

Device G

Device H

Device I

Port 1 (Access Port
PVID 5)

Port 7 (Access Port
PVID 4)

Port 5 (Access Port

PVID 3)

Port 4 (Access
Port PVID 2)

Port 2 (Trunk Port PVID 2,
Fixed VLAN (Tagged)=3,4)

Port 6 (Access Port PVID 5)

HUB

In this application,
 Port 1 connects a single untagged device and assigns it to VLAN 5; it should be configured as

“Access Port” with PVID 5.

 Port 2 connects a LAN with two untagged devices belonging to VLAN 2. One tagged device

with VID 3 and one tagged device with VID 4. It should be configured as “Trunk Port” with
PVID 2 for untagged device and Fixed VLAN (Tagged) with 3 and 4 for tagged device. Since
each port can only have one unique PVID, all untagged devices on the same port can only
belong to the same VLAN.

 Port 3 connects with another switch. It should be configured as “Trunk Port.” GVRP protocol

will be used through the Trunk Port.

 Port 4 connects a single untagged device and assigns it to VLAN 2; it should be configured as

“Access Port” with PVID 2.

 Port 5 connects a single untagged device and assigns it to VLAN 3; it should be configured as

“Access Port” with PVID 3.

 Port 6 connect a single untagged device and assigns it to VLAN 5; it should be configured as

“Access Port” with PVID 5.

 Port 7 connects a single untagged device and assigns it to VLAN 4; it should be configured as

“Access Port” with PVID 4.

EDS-508A/505A Series User’s Manual Featured Functions

3-57

After proper configuration:

 Packets from device A will travel through “Trunk Port 3” with tagged VID 5. Switch B will

recognize its VLAN, pass it to port 6, and then remove tags received successfully by device G,
and vice versa.

 Packets from device B and C will travel through “Trunk Port 3” with tagged VID 2. Switch B

recognizes its VLAN, passes it to port 4, and then removes tags received successfully by device
F, and vice versa.

 Packets from device D will travel through “Trunk Port 3” with tagged VID 3. Switch B will

recognize its VLAN, pass to port 5, and then remove tags received successfully by device H.
Packets from device H will travel through “Trunk Port 3” with PVID 3. Switch A will
recognize its VLAN and pass it to port 2, but will not remove tags received successfully by
device D.

 Packets from device E will travel through “Trunk Port 3” with tagged VID 4. Switch B will

recognize its VLAN, pass it to port 7, and then remove tags received successfully by device I.
Packets from device I will travel through “Trunk Port 3” with tagged VID 4. Switch A will
recognize its VLAN and pass it to port 2, but will not remove tags received successfully by
device E.

Configuring Virtual LAN

VLAN Settings

To configure the EDS’s 802.1Q VLAN, use the VLAN Setting page to configure the ports.

EDS-508A/505A Series User’s Manual Featured Functions

3-58

VLAN Mode

Setting Description Factory Default

802.1Q VLAN Set VLAN mode to 802.1Q VLAN
Port-based VLAN Set VLAN mode to Port-based VLAN

802.1Q VLAN

Management VLAN ID

Setting Description Factory Default

VLAN ID ranges
from 1 to 4094

Set the management VLAN of this EDS. 1

Enable GVRP

Setting Description Factory Default

Enable/Disable

Select the option to enable/disable the GVRP
function.

Enable

Port Type

Setting Description Factory Default

Access This port type is used to connect single devices

without tags.

Trunk Select “Trunk” port type to connect another

802.1Q VLAN aware switch or another LAN that
combines tagged and/or untagged devices and/or
other switches/hubs.

Access

ATTENTION

For communication redundancy in the VLAN environment, set “Redundant Port,” “Coupling
Port,” and “Coupling Control Port” as “Trunk Port,” since these ports act as the “backbone” to
transmit all packets of different VLANs to different EDS units.

Port PVID

Setting Description Factory Default

VID range from 1
to 4094

Set the port default VLAN ID for untagged devices that
connect to the port.

1

Fixed VLAN List (Tagged)

Setting Description Factory Default

VID range from 1
to 4094

This field will be active only when selecting the “Trunk”
port type. Set the other VLAN ID for tagged devices that
connect to the “Trunk” port. Use commas to separate
different VIDs.

None

Forbidden VLAN List

Setting Description Factory Default

VID range from 1
to 4094

This field will be active only when selecting the “Trunk”
port type. Set the VLAN IDs that will not be supported
by this trunk port. Use commas to separate different
VIDs.

None

EDS-508A/505A Series User’s Manual Featured Functions

3-59

To configure the EDS’s Port-based VLAN, use the VLAN Setting page to configure the ports.

VLAN Mode

Setting Description Factory Default

802.1Q VLAN Set VLAN mode to 802.1Q VLAN
Port-based VLAN Set VLAN mode to Port-based VLAN

802.1Q VLAN

Port

Setting Description Factory Default

Enable/Disable Set port to specific VLAN Group. Enable

(all ports belong to
VLAN1)

VLAN Table

In 802.1Q VLAN table, you can review the VLAN groups that were created, Joined Access Ports,
and Trunk Ports, and in Port-based VLAN table, you can review the VLAN group and Joined port.

EDS-508A/505A Series User’s Manual Featured Functions

3-60

NOTE

The physical network can have a maximum of 64 VLAN settings.

Using Multicast Filtering

Multicast filtering improves the performance of networks that carry multicast traffic. This section
explains multicasts, multicast filtering, and how multicast filtering can be implemented on your
EDS.

The Concept of Multicast Filtering

What is an IP Multicast?

A multicast is a packet sent by one host to multiple hosts. Only those hosts that belong to a
specific multicast group will receive the multicast. If the network is set up correctly, a multicast
can only be sent to an end-station or a subset of end-stations on a LAN or VLAN that belong to
the multicast group. Multicast group members can be distributed across multiple subnets, so that
multicast transmissions can occur within a campus LAN or over a WAN. In addition, networks
that support IP multicast send only one copy of the desired information across the network until
the delivery path that reaches group members diverges. To make more efficient use of network
bandwidth, it is only at these points that multicast packets are duplicated and forwarded. A
multicast packet has a multicast group address in the destination address field of the packet’s IP
header.

Benefits of Multicast

The benefits of using IP multicast are that it:
 Uses the most efficient, sensible method to deliver the same information to many receivers with

only one transmission.

 Reduces the load on the source (for example, a server) since it will not need to produce several

copies of the same data.

 Makes efficient use of network bandwidth and scales well as the number of multicast group

members increases.

 Works with other IP protocols and services, such as Quality of Service (QoS).
Multicast transmission makes more sense and is more efficient than unicast transmission for some

applications. For example, multicasts are often used for video-conferenci n g, since hi g h vol umes of
traffic must be sent to several end-stations at the same time, but where broadcasting the traffic to
all end-stations would cause a substantial reduction in network performance. Furthermore, several
industrial automation protocols, such as Allen-Bradley, EtherNet/IP, Siemens Profibus, and
Foundation Fieldbus HSE (High Speed Ethernet), use multicast. These industrial Ethernet
protocols use publisher/subscri ber com munications models by multicasting packets that could
flood a network with heavy traffic. IGMP Snooping is used to prune multicast traffic so that it
travels only to those end destinations that require the traffic, reducing the amount of traffic on the
Ethernet LAN.

Multicast Filtering

Multicast filtering ensures that only end-stations that have joined certain groups receive multicast
traffic. With multicast filtering, network devices only forward multicast traffic to the ports that are
connected to registered end-stations. The following two figures illustrate how a network behaves
without multicast filtering, and with multicast filtering.

EDS-508A/505A Series User’s Manual Featured Functions

3-61

Network without multicast filtering

12345678

Serial ports

Console LAN

910111213141516

IGMP Group2

Group 1 Multicast Stream Group 2 Multicast Stream

IGMP Group1 IGMP Group2 IGMP Group1

All hosts receive the multicast traffic, even if they don’t need it.
Network with multicast filtering

IGMP Group2

Group 1 Multicast Stream Group 2 Multicast Stream

IGMP Group1 IGMP Group2 IGMP Group1

Hosts only receive dedicated traffic from other hosts belonging to the same group.

EDS-508A/505A Series User’s Manual Featured Functions

3-62

Multicast Filtering and Moxa EtherDevice Switch

The EDS has three ways to achieve multicast filtering: IGMP (Internet Group Management
Protocol) Snooping, GMRP (GARP Multicast Registration Protocol), and adding a static multicast
MAC manually to filter multicast traffic automatically.

IGMP (Internet Group Management Protocol)
Snooping Mode

Snooping Mode allows your switch to forward multicast packets only to the appropriate ports. The
switch “snoops” on exchanges between hosts and an IGMP device, such as a router, to find those
ports that want to join a multicast group, and then configures its filters accordingly.

Query Mode

Query mode allows the EDS to work as the Querier if it has the lowest IP address on the
subnetwork to which it belongs. IGMP querying is enabled by default on the EDS to help prevent
interoperability issues with some multicast routers that may not follow the lowest IP address
election method. Enable query mode to run multicast sessions on a network that does not contain
IGMP routers (or queriers).

NOTE

The EDS is compatible with any device that conforms to the IGMP v2 device protocol.

IGMP Multicast Filtering

IGMP is used by IP-supporting network devices to register hosts with multicast groups. It can be
used on all LANs and VLANs that contain a multicast capable IP router, and on other network
devices that support multicast filtering. IGMP works as follows:

1. The IP router (or querier) periodically sends query packets to all end-stations on the LANs or

VLANs that are connected to it. For networks with more than one IP router, the router with
the lowest IP address is the querier. A switch with IP address lower than the IP address of any
other IGMP queriers connected to the LAN or VLAN can become the IGMP querier.

2. When an IP host receives a query packet, it sends a report packet back that identifies the

multicast group that the end-station would like to join.

3. When the report packet arrives at a port on a switch with IGMP Snooping enabled, the switch

knows that the port should forward traffic for the multicast group, and then proceeds to
forward the packet to the router.

4. When the router receives the report packet, it registers that the LAN or VLAN requires traffic

for the multicast groups.

5. When the router forwards traffic for the multicast group to the LAN or VLAN, the switches

only forward the traffic to ports that received a report packet.

EDS-508A/505A Series User’s Manual Featured Functions

3-63

GMRP (GARP Multicast Registration Protocol)

The EDS supports IEEE 802.1D-1998 GMRP (GARP Multicast Registration Protocol), which
differs from IGMP (Internet Group Management Protocol). GMRP is a MAC-based multicast
management protocol, whereas IGMP is IP-based. GMRP provides a mechanism that allows
bridges and end stations to register or de-register Group membership information dynamically.
GMRP functions similarly to GVRP, except that GMRP registers multicast addresses on ports.
When a port receives a GMRP-join message, it will register the multicast address to its database if
the multicast address is not registered, and all the multicast packets with that multicast address are
able to be forwarded from this port. When a port receives a GMRP-leave message, it will
de-register the multicast address from its database, and all the multicast packets with this multicast
address are not able to be forwarded from this port.

Static Multicast MAC

Some devices may only support multicast packets, but not support either IGMP Snooping or
GMRP. The EDS supports adding multicast groups manually to enable multicast filtering.

Enabling Multicast Filtering

Use the serial console or Web interface to enable or disable IGMP Snooping and IGMP querying.
If IGMP Snooping is not enabled, then IP multicast traffic is always forwarded, flooding the
network.

Configuring IGMP Snooping

IGMP Snooping provides the ability to prune multicast traffic so that it travels only to those end
destinations that require that traffic, thereby reducing the amount of traffic on the Ethernet LAN.

IGMP Snooping Settings

IGMP Snooping Enable

Setting Description Factory Default

Enable/Disable Select the option to enable the IGMP Snooping

function globally.

Disabled

IGMP Snooping Enhanced Mode

Setting Description Factory Default

Enable IGMP Multicast packets will forward to : Enable

EDS-508A/505A Series User’s Manual Featured Functions

3-64

 Learned Multicast Querier Ports
 Member Por t s

Disable IGMP Multicast packets will forward to :

 Learned multicast Querier Ports
 Static Multicast Querier Ports
 Querier Connected Ports
 Member Por t s

Query Interval

Setting Description Factory Default

Numerical value
input by user

Set the query interval of the Querier function globally.
Valid settings are from 20 to 600 seconds.

125 seconds

IGMP Snooping

Setting Description Factory Default

Enable/Disable Select the option to enable the IGMP Snooping

function per VLAN.

Enabled if IGMP
Snooping Enabled
Globally

NOTE

We suggest the following IGMP Snooping configurations-

 When the network is mixed with third party switches, such as Cisco:

‧ IGMP Snooping Enable-

　

‧ IGMP Snooping Enhanced Mode- □

 When the network consists entirely of Moxa switches:

‧ IGMP Snooping Enable-



‧ IGMP Snooping Enhanced Mode-



Querier

Setting Description Factory Default

Enable/Disable Select the option to enable the EDS’s querier function. Enabled if IGMP

Snooping is Enabled
Globally

Static Multicast Router Port

Setting Description Factory Default

Select/Deselect Select the option to select which ports will connect to

the multicast routers. It’s active only when IGMP
Snooping is enabled.

Disabled

NOTE

At least one switch must be designated the Querier or enable IGMP snooping and GMRP when
enabling Turbo Ring and IGMP snooping simultaneously.

EDS-508A/505A Series User’s Manual Featured Functions

3-65

IGMP Table

The EDS displays the current active IGMP groups that were detected.

The information includes VID, Auto-learned Multicast Router Port, Static Multicast Router
Port, Querier Connected Port, and the IP and MAC addresses of active IGMP groups.

Static Multicast MAC

If required, the EDS also supports adding multicast groups manually.

Add New Static Multicast Address to the List

Setting Description Factory Default

MAC Address Inpu t the multicast MAC address of this host. None

MAC Address

Setting Description Factory Default

integer Input the number of the VLAN to which the host with

this MAC Address belongs.

None

Join Port

Setting Description Factory Default

Select/Deselect Select the appropriate options to select the join ports for

this multicast group.

None

EDS-508A/505A Series User’s Manual Featured Functions

3-66

Configuring GMRP

GMRP is a MAC-based multicast management protocol, whereas IGMP is IP-based. GMRP
provides a mechanism that allows bridges and end stations to register or un-register Group
membership information dynamically.

GMRP enable

Setting Description Factory Default

Enable/Disable Select the option to enable the GMRP function for the

port listed in the Port column

Disable

GMRP Table

The EDS displays the current active GMRP groups that were detected.

Setting Description

Fixed Ports This multicast address is defined by static multicast.
Learned Ports This multicast address is learned by GMRP.

EDS-508A/505A Series User’s Manual Featured Functions

3-67

Using Bandwidth Management

In general, one host should not be allowed to occupy unlimited bandwidth, particularly when the
device malfunctions. For example, so-called “broadcast storms” could be caused by an incorrectly
configured topology, or a malfunctioning device. The EDS not only prevents broadcast storms, but
can also be configured to a different ingress rate for all packets, giving administrators full control
of their limited bandwidth to prevent undesirable effects caused by unpredictable faults.

Configuring Bandwidth Management

Traffic Rate Limiting Settings

Ingress

Setting Description Factory Default

Ingress rate Select the ingress rate for all packets from the following

options: not limited, 128K, 256K, 512K, 1M, 2M, 4M,
8M

N/A

Using Port Access Control

The EDS provides two kinds of Port-Based Access Controls. One is Static Port Lock and the other
is IEEE 802.1X.

Static Port Lock

The EDS can also be configured to protect static MAC addresses for a specific port. With the Port
Lock function, these locked ports will not learn any additional addresses, but only allow traffic
from preset static MAC addresses, helping to block crackers and careless usage.

IEEE 802.1X

The IEEE 802.1X standard defines a protocol for client/server-based access control and
authentication. The protocol restricts unauthorized clients from connecting to a LAN through ports
that are open to the Internet, and which otherwise would be readily accessible. The purpose of the
authentication server is to check each client that requests access to the port. The client is only
allowed access to the port if the client’s permission is authenticated.

EDS-508A/505A Series User’s Manual Featured Functions

3-68

The IEEE 802.1X Concept

Three components are used to create an authentication mechanism based on 802.1X standards:
Client/Supplicant, Authentication Server, and Authenticator.

Supplicant: The end station that requests access to the LAN and switch services and responds to
the requests from the switch.

Authentication server: The server that performs the actual authentication of the supplicant.
Authenticator: Edge switch or wireless access point that acts as a proxy between the supplicant

and the authentication server, requesting identity information from the supplicant, verifying the
information with the authentication server, and relaying a response to the supplicant.

The EDS acts as an authenticator in the 802.1X environment. A supplicant and an authenticator
exchange EAPOL (Extensible Authentication Protocol over LAN) frames with each other. We can
either use an external RADIUS server as the authentication server, or implement the authentication
server in the EDS by using a Local User Database as the authentication look-up table. When we
use an external RADIUS server as the authenticatio n server, the authen ticator and the
authentication server exchange EAP frames between each other.

Authentication can be initiated either by the supplicant or the authenticator . When the supplicant
initiates the authentication process, it sends an “EAPOL-Start” frame to the authenticator. When
the authenticator initiates the authentication process or when it receives an “EAPOL Start” frame,
it sends an “EAP Request/Identity” frame to ask for the username of the supplicant. The following
actions are described below:

Message Exchange

Authentication

server

(RADIUS)

Client

EAPOL-Start

EAP-Request/Identity

EAP-Response/Identity

EAP-Request/OTP

EAP-Response/OTP

EAP-Success

EAPOL-Logoff

Port Authorized

Port Unauthorized

RADIUS Access-Request

RADIUS Access-Challenge

RADIUS Access-Request

RADIUS Access-Accept

EDS-508A/505A Series User’s Manual Featured Functions

3-69

1. When the supplicant receives an “EAP Request/Identity” frame, it sends an “EAP

Response/Identity” frame with its username back to the authenticator.

2. If the RADIUS server is used as the authentication server, the authenticator relays the “EAP

Response/Identity” frame from the supplicant by encapsulating it into a “RADIUS
Access-Request” frame and sends to the RADIUS server. When the authentication server
receives the frame, it looks up its database to check if the username exists. If the username is
not present, the authentication server replies with a “RADIUS Access-Reject” frame to the
authenticator if the server is a RADIUS server or just indicates failure to the authenticator if
the Local User Database is used. The authenticator sends an “EAP-Failure” frame to the
supplicant.

3. The RADIUS server sends a “RADIUS Access-Challenge,” which contains an “EAP Request”

with an authentication type to the authenticator to ask for the passwo rd from the client. RFC
2284 defines several EAP authentication types, such as “MD5-Challenge,” “One-Time
Password,” and “Generic Token Card.” Currently, only “MD5-Challenge” is supported. If the
Local User Database is used, this step is skipped.

4. The authenticator sends an “EAP Request/MD5-Challenge” frame to the supplicant. If the

RADIUS server is used, th e “EAP Request/MD5-Challenge” frame is retrieved directly from
the “RADIUS Access-Challenge” frame.

5. The supplicant responds to the “EAP Request/MD5-Challenge” by sending an “EAP

Response/MD5-Challenge” frame that encapsulates the user’s password using the MD5 hash
algorithm.

6. If the RADIUS server is used as the authentication server, the authenticator relays the “EAP

Response/MD5-Challenge” frame from the supplicant by encapsulating it into a “RADIUS
Access-Request” frame along with a “Shared Secret,” which must be the same within the
authenticator and the RADIUS server, and sends the frame to the RADIUS server. The
RADIUS server checks against the password with its database, and replies with “RADIUS
Access-Accept” or “RADIUS Access-Reject” to the authenticator. If the Local User Database
is used, the password is checked against its database and indicates success or failure to the
authenticator.

7. The authenticator sends “EAP Success” or “EAP Failure” based on the reply from the

authentication server.

Configuring Static Port Lock

The EDS supports adding unicast groups manually if required.

Setting Description Factory Default

MAC Address Add the static unicast MAC address into the address

table.

None

Port Fix the static address with a dedicated port. 1

EDS-508A/505A Series User’s Manual Featured Functions

3-70

Configuring IEEE 802.1X

Database Option

Setting Description Factory Default

Local
(Max. 32 users)

Select this option when setting the Local User
Database as the authentication database.

Local

Radius Select this option to set an external RADIUS server as

the authentication database. The authentication
mechanism is “EAP-MD5.”

Local

Radius, Local Select this option to make an external RADIUS server

as the authentication database with first priority. The
authentication mechanism is “EAP-MD5.” The first
priority is to set the Local User Database as the
authentication database.

Local

Radius Server

Setting Description Factory Default

IP address or
domain name

The IP address or domain name of the RADIUS server localhost

Server Port

Setting Description Factory Default

Numerical The UDP port of the RADIUS Server 1812

Shared Key

Setting Description Factory Default

alphanumeric
(Max. 40
characters)

A key to be shared between the external RADIUS server
and The EDS. Both ends must be configured to use the
same key.

None

EDS-508A/505A Series User’s Manual Featured Functions

3-71

Re-Auth

Setting Description Factory Default

Enable/Disable Select to require re-authentication of the client after a

preset time period of no activity has elapsed.

Disable

Re-Auth Period

Setting Description Factory Default

Numerical
(60-65535 sec.)

Specify how frequently the end stations need to reenter
usernames and passwords in order to stay connected.

3600

802.1X

Setting Description Factory Default

Enable/Disable Select the option under the 802.1X column to enable

IEEE 802.1X for one or more ports. All end stations
must enter usernames and passwords before access to
these ports is allowed.

Disable

802.1X Re-Authentication

The EDS can force connected devices to be re-authorized manually.

802.1X Re-Authentication

Setting Description Factory Default

Enable/Disable Select the option to enable 802.1X Re-Authentication Disable

EDS-508A/505A Series User’s Manual Featured Functions

3-72

Local User Database Setup

When setting the Local User Database as the authentication database, set the database first.

Local User Database Setup

Setting Description Factory Default

User Name
(Max. 30 characters)

User Name for Local User Database None

Password
(Max. 16 characters)

Password for Local User Database None

Description
(Max. 30 characters)

Description for Local User Database None

NOTE

The user name for the Local User Database is case-insensitive.

Port Access Control Table

The port status will indicate whether the access is authorized or unauthorized.

EDS-508A/505A Series User’s Manual Featured Functions

3-73

Using Auto Warning

Since industrial Ethernet devices are often located at the endpoints of a system, these devices will
not always know what is happening elsewhere on the network. This means that an industrial
Ethernet switch that connects to these devices must provide system maintainers with real-time
alarm messages. Even when control engineers are out of the control room for an extended period
of time, they can still be informed of the status of devices almost instantaneously when exceptions
occur. The EDS supports different approaches to warn engineers automatically, such as by using
email and relay output. It also supports two digital inputs to integrate sensors into your system to
automate alarms using email and relay output.

Configuring Email Warning

The Auto Email Warning function uses e-mail to alert the user when certain user-configured
events take place.

Three basic steps are required to set up the Auto Warning function:

1. Configuring Email Event Types

Select the desired Event types from the Console or Web Browser Event type page (a
description of each event type is given later in the Email Alarm Events setting subsection).

2. Configuring Email Settings

To configure the EDS’s email setup from the Console interface or browser interface, enter
your Mail Server IP/Name (IP address or name), Account Name, Account Password, Retype
New Password, and the email address to which warning messages will be sent.

3. Activate your settings and if necessary, test the email

After configuring and activating your EDS’s Event Types and Email Setup, you can use the
Test Email function to see if your e-mail addresses and mail server address have been
properly configured.

Event Type

Event Types can be divided into two basic groups: System Events and Port Events. System
Events are related to the overall function of the switch, whereas Port Events are related to the
activity of a specific port.

EDS-508A/505A Series User’s Manual Featured Functions

3-74

System Events Warning e-mail is sent when…

Switch Cold Start Power is cut off and then reconnected.
Switch Warm Start The EDS is rebooted, such as when network

parameters are changed (IP address, subnet mask,

etc.).
Power Transition (OnOff) The EDS is powered down.
Power Transition (OffOn) The EDS is powered up.
DI1 (OnOff) Digital Input 1 is triggered by on to off transition
DI1 (OffOn) Digital Input 1 is triggered by off to on transition
DI2 (OnOff) Digital Input 2 is triggered by on to off transition
DI2 (OffOn) Digital Input 2 is triggered by off to on transition
Configuration Change Activated A configuration item has been changed.
Authentication Failure An incorrect password is entered.
Comm. Redundancy Topology

Changed

Spanning Tree Protocol switches have changed their

position (applies only to the root of the tree).

The Master of the Turbo Ring has changed or the

backup path is activated.

Port Events Warning e-mail is sent when…

Link-ON The port is connected to another device.
Link-OFF

The port is disconnected (e.g., the cable is pulled out,

or the opposing device shuts down).
Traffic-Overload

The port’s traffic surpasses the Traffic-Threshold for

that port (provided this item is Enabled).
Traffic-Threshold (%)

Enter a non-zero number if the port’s

Traffic-Overload item is Enabled.

Traffic-Duration (sec.)

A Traffic-Overload warning is sent every

Traffic-Duration seconds if th e average

Traffic-Threshold is surpassed during that time

period.

NOTE

The Traffic-Overload, Traffic-Threshold (%), and Traffic-Duration (sec.) Port Event items
are related. If you Enable the Traffic-Overload event, then be sure to enter a non-zero
Traffic-Threshold percentage, as well as a Traffic-Durati on bet ween 1 and 300 seconds.

NOTE

Warning e-mail messages will have the sender field formatted in the form:

Moxa_EtherDevice_Switch_0001@Switch_Location

where Moxa_EtherDevice_Switch is the default Switch Name, 0001 is the EDS’s serial number,
and Switch_Location is the default Server Location.

Refer to the Basic Settings section to see how to modify Switch Name and Switch Location.

EDS-508A/505A Series User’s Manual Featured Functions

3-75

Email Setup

Mail Server IP/Name

Setting Description Factory Default

IP address The IP Address of your email server. None

Account Name

Setting Description Factory Default

Max. 45
Characters

Your email account name (typically your user name) None

Password Setting

Setting Description Factory Default

Disable/Enable to
change Password

To reset the Password from the Web Browser interface,
click the Change password check-box, type the Old
Password, type the New Password, retype the New
password, and then click Activate; Max. 45 Characters.

Disable

Old Password Type the current password when changing the password None
New Password Type new password when enabled to change password;

Max. 45 Characters.

None

Retype Password If you type a new password in the Password field, you

will be required to retype the password in the Retype
new password field before updating the new password.

None

Email Address

Setting Description Factory Default

Max. 30
characters

You can set up to 4 email addresses to receive alarm
emails from the EDS.

None

Send Test Email

After configuring the email settings, you should first click Activate to activate those settings, and
then click Send Test Email to verify that the settings are correct.

EDS-508A/505A Series User’s Manual Featured Functions

3-76

NOTE

Auto warning e-mail messages will be sent through an authentication protected SMTP server that
supports the CRAM-MD5, LOGIN, and PLAIN methods of SASL (Simple Authentication and
Security Layer) authentication mechanism.

We strongly recommend not entering your Account Name and Account Password if auto warning
e-mail messages can be delivered without using an authentication mechanism.

Configuring Relay Warning

The Auto Relay Warning function uses relay output to alert the user when certain user-configured
events take place. There are two basic steps required to set up the Relay Warning function:

1. Configuring Relay Event Types

Select the desired Event types from the Console or Web Browser Event type page (a
description of each event type is given later in the Relay Alarm Events setting subsection).

2. Activate your settings

After completing the configuration procedure, you will need to activate your EDS’s Relay
Event Types.

Event Setup

Event Types can be divided into two basic groups: System Events and Port Events. System
Events are related to the overall function of the switch, whereas Port Events are related to the
activity of a specific port.

The EDS supports two relay outputs. You can configure which relay output is related to which
events. This helps administrators identify the importance of the different events.

EDS-508A/505A Series User’s Manual Featured Functions

3-77

System Events Warning Rel a y output is triggered when…

Power Transition (OnOff) The EDS is powered on.
Power Transition (OffOn) The EDS is powered down.
DI1 (OnOff) Digital Input 1 is triggered by on to off transition
DI1 (OffOn) Digital Input 1 is triggered by off to on transition
DI2 (OnOff) Digital Input 2 is triggered by on to off transition
DI2 (OffOn) Digital Input 2 is triggered by off to on transition

Port Events Warning e-mail is sent when…

Link-ON The port is connected to another device.
Link-OFF

The port is disconnected (e.g., the cable is pulled out,

or the opposing device shuts down).
Traffic-Overload

The port’s traffic surpasses the Traffic-Threshold for

that port (provided this item is Enabled).
Traffic-Threshold (%)

Enter a non-zero number if the port’s

Traffic-Overload item is Enabled.

Traffic-Duration (sec.)

A Traffic-Overload warning is sent every

Traffic-Duration seconds if th e average

Traffic-Threshold is surpassed during that time

period.

NOTE

The Traffic-Overload, Traffic-Threshold (%), and Traffic-Duration (sec) Port Event items
are related. If you Enable the Traffic-Overload event, then be sure to enter a non-zero
Traffic-Threshold percentage, as well as a Traffic-Durati on bet ween 1 and 300 seconds.

Override relay alarm settings

Select this option to override the relay warning setting temporarily. Releasing the relay output will
allow administrators to fix any problems with the warning condition.

Warning List

Use this table to see if any relay alarms have been issued.

EDS-508A/505A Series User’s Manual Featured Functions

3-78

Using Line-Swap-Fast-Recovery

The Line-Swap Fast Recovery function, which is enabled by default, allows the EDS to return to
normal operation extremely quickly after devices are unplugged and then re-plugged into different
ports. The recovery time is on the order of a few milliseconds (compare this with standard
commercial switches for which the recovery time could be on the order of several minutes). To
disable the Line-Swap Fast Recovery function, or to re-enable the function after it has already
been disabled, access either the Console utility’s Line-Swap recovery page, or the Web Browser
interface’s Line-Swap fast recovery page, as the following figure shows:

Configuring Line-Swap Fast Recovery

Enable Line-Swap-Fast-Recovery

Setting Description Factory Default

Enable/Disable Select this option to enable the

Line-Swap-Fast-Recovery function

Enable

Using Set Device IP

To reduce the effort required to set up IP addresses, the EDS comes equipped with DHCP/BOOTP
server and RARP protocol to set up IP addresses of Ethernet-enabled devices automatically.

When enabled, the Set device IP function allows The EDS to assign specific IP addresses
automatically to connected devices that are equIPped with DHCP Client or RARP protocol. In
effect, the EDS acts as a DHCP server by assigning a connected device with a specific IP address
stored in its internal memory. Each time the connected device is switched on or rebooted, the EDS
sends the device the desired IP address.

Perform the following steps to use the Set device IP function:

EDS-508A/505A Series User’s Manual Featured Functions

3-79

STEP 1—set up the connected devices
Set up those Ethernet-enabled devices connected to

the EDS for which you would like IP addresses to be
assigned automatically. The devices must be
configured to obtain their IP address automatically.

The devices’ configuration utility should include a
setup page that allows you to choose an option
similar to Obtain an IP address automatically.

For example, Windows’ TCP/IP Properties window
is shown at the right. Although your device’s
configuration utility may look quite a bit different,
this figure should give you some idea of what to look
for.

You also need to decide to which of the EDS’s ports
your Ethernet-enabled devices will be connected.
You will need to set up each of these ports separately,
as described in the following step.

STEP 2
Configure the EDS’s Set device IP function, either from the Console utility or from the Web

Browser interface. In either case, you simply need to enter the Desired IP for each port that needs
to be configured.

STEP 3
Be sure to activate your settings before exiting.

 When using the Web Browser interface, activate by clicking Activate.
 When using the Console utility, activate by first highlighting the Activate menu option, and

then press Enter. You should receive the Set device IP settings are now active! (Press any
key to continue) message.

Configuring Set Device IP

EDS-508A/505A Series User’s Manual Featured Functions

3-80

Desired IP Address

Setting Description Factory Default

IP Address Set the desired IP of connected devices. None
The DHCP Relay Agent makes it possible for DHCP broadcast messages to be sent over routers.

The DHCP Relay Agent enables DHCP clients to obtain IP addresses from a DHCP server on a
remote subnet, or those that are not located on the local subnet.

DHCP Relay Agent (Option 82)

Option 82 is used by the relay agent to insert additional information into the client’s DHCP
request. The Relay Agent Information option is inserted by the DHCP relay agent when
forwarding client-originated DHCP pac ket s to a DHCP server. Servers can recognize the Relay
Agent Information option and use the information to implement IP addresses to Clients.

When Option 82 is enabled on the switch, a subscriber device is identified by the switch port
through which it connects to the network (in addition to its MAC address). Multiple hosts on the
subscriber LAN can be connected to the same port on the access switch and are uniquely
identified.

The Option 82 information contains 2 sub-options: Circuit ID and Remote ID, which define the
relationship between end device IP and the DHCP Option 82 server. The “Circuit ID” is a 4-byte
number generated by the Ethernet switch—a combination of physical port number and VLAN ID.
The format of the “Circuit ID” is as described below:

FF–VV–VV–PP

Where the first byte “FF” is fixed to “01”, the second and the third byte “VV-VV” is formed by
the port VLAN ID in hex, and the last byte “PP” is formed by the port number in hex. For
example,

01–00–0F–03 is the “Circuit ID” of port number 3 with port VLAN ID 15.
The “Remote ID” is to identify the relay agent itself and it can be one of the following:

1. The IP address of the relay agent.

2. The MAC address of the relay agent.

3. A co mbin ation of IP address and MAC address of the relay agent.

4. A user-defined string.

EDS-508A/505A Series User’s Manual Featured Functions

3-81

Using Diagnosis

The EDS provides two important tools for administrators to diagnose network systems.

Mirror Port

The Mirror port function can be used to monitor data being transmitted through a specific port.
This is done by setting up another port (the mirror port) to receive the same data being transmitted
from, or both to and from, the port under observation. This allows the network administrator to
“sniff” the observed port and thus keep tabs on network activity.

EDS-508A/505A Series User’s Manual Featured Functions

3-82

Perform the following steps to set up the Mirror Port function:
STEP 1

Configure the EDS’s Mirror Port function from either the Console utility or Web Browser
interface. You will need to configure three settings:

Monitored Port

Select the port number of the port whose network activity will be
monitored.

Mirror Port

Select the port number of the port that will be used to monitor the
activity of the monitored port.

Watch Direction

Select one of the following three watch direction options:

 Input data stream

Select this option to monitor only those data packets coming in
through the EDS’s port.

 Output data stream

Select this option to monitor only those data packets being sent out
through the EDS’s port.

 Bi-directional

Select this option to monitor data packets both coming into, and
being sent out through, the EDS’s port.

STEP 2
Be sure to activate your settings before exiting.

 When using the Web Browser interface, activate by clicking Activate.
 When using the Console utility, activate by first highlighting the Activate menu option, and

then press Enter. You should receive the Mirror port settings are now active! (Press any key
to continue) message.

Ping

The Ping function uses the ping command to give users a simple but powerful tool for
troubleshooting network problems. The function’s most unique feature is that even though the
ping command is entered from the user’s PC keyboard, the actual ping command originates from
EDS itself. In this way, the user can essentially control the EDS and send ping commands out
through its ports.

To use the Ping function, type in the desired IP address, and then press Enter from the Console
utility, or click Ping when using the Web Browser interface.

EDS-508A/505A Series User’s Manual Featured Functions

3-83

LLDP Function Overview

Defined by IEEE 802.11AB, LLDP is an OSI Layer 2 Protocol that standardizes the metho dology
of self-identity advertisement. It allows each networking device, e.g. a Moxa managed switch, to
periodically inform its neighbors about its self-information and configurations. As a result, all of
the devices would have knowledge about each other; and through SNMP, this knowledge can be
transferred to Moxa’s MXview for auto-topology and network visualization.

LLDP Web Interface

From the switch’s web interface, users have the option of either enabling or disabling the LLDP,
as well as setting the LLDP transmit interval (as shown in the figure below). In addition, users are
able to view each switch’s neighbor-list, which is reported by its network neighbors. Most
importantly, enabling the LLDP function allows Moxa’s MXview to automatically display the
network’s topology as well as system setup details such as VLAN, and Trunking for the entire
network.

EDS-508A/505A Series User’s Manual Featured Functions

3-84

LLDP Settings

Enable LLDP

Setting Description Factory Default

Enable or Disable Enable or disable LLDP function. Enable

Value

Setting Description Factory Default

Numbers from
5~32768 secs

To set the transmit interval of LLDP messages. Unit is
in seconds.

30 (seconds)

LLDT Table

Port Neighbor ID Neighbor Port

Neighbor Port

Description

Neighbor System

Port: The port number that connects to the neighbor device.
Neighbor ID: A unique entity which identifies a neighbor device; this is typically the MAC

address.

Neighbor Port: The port number of the neighbor device.
Neighbor Port Description: A textual description of the neighbor device’s interface.
Neighbor System: Hostname of the neighbor device.

EDS-508A/505A Series User’s Manual Featured Functions

3-85

Using Monitor

You can monitor statistics in real time from the EDS’s web console and serial console.

Monitor by Switch

Access the Monitor by selecting “System” from the left selection bar. Monitor by System allows
the user to view a graph that shows the combined data transmission activity of all of the EDS’s
ports. Click one of the four options—Total Packets, TX Packets, RX Packets, or Error
Packets—to view transmission activity of specific types of packets. Recall that TX Packets are
packets sent out from the EDS, RX Packets are packets received from connected devices, and
Error Packets are packets that did not pass TCP/IP’s error checking algorithm. The Total Packets
option displays a graph that combines TX, RX, and TX Error, RX Error Packets activ ity. The
graph displays data transmission activity by showing Packets/s (i.e., packets per second, or pps)
versus sec. (seconds). In fact, three curves are displayed on the same graph: Unicast packets (in
red color), Multicast packets (in green color), and Broadcast packets (in blue color). The graph is
updated every few seconds, allowing the user to analyze data transmission activity in real-time.