IBM OPTIONS ATM OC-3c User Manual

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8271 Nways Ethernet LAN Switch ATM OC-3c Module

User’s Guide

Before using this inform ation an d the prod uct i t supports, b e sure

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mation” and Appendix F, “Notices, Trademarks, and Warranties”.

First Edition (October 1997)

This e ditio n ap pl ies t o the IB M 82 71 Nw ays Eth er net L A N Swi tch ATM

3C-Oc Module with agent software version 1.05 and IBM 8271 Nways

Ethernet LAN Switch Models 524, 612, 624, 712 with agent software

version 3.1.

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ONTENTS

BOUT THIS GUIDE

Introduc tion 1 Terminology 1

AT M Te rmino logy 1 Finding Information in This Guide 2 Conventions 2 Related Documentation 3

EATURES AND BENEFITS

ATM Benefits 1-1 ATM Module Features 1-2

ETWORK LAYER CONCEPTS

The Layered Network Architecture 2-1 Upper Layer Protocols 2-2 What is LAN Emulation (LANE)? 2-2

LAN Emulation Components 2-3

LAN Emulation Client (LEC) 2-3 LAN Emulation Server (LES) 2-3 Broadcast and Unknown Server (BUS) 2-3 LAN Emulation Configuration Server (LE C S) 2-3

LAN Emulation Components in Your Network 2-4

LAN Emulation and IBM Dev ices 2-4

Joining th e ELAN 2- 5

Locating the LECS 2-5

Mapping Ethernet and ATM Addresses 2-6

Address Resolution 2-6 LAN Emulation Address Resolution Protocol (LE_ARP)

2-7 What Happens to Unic ast Frames? 2-7 What Happens to Broadcast and Mult icast Frames? 2-7

AT M Adaptation Layer (AAL) 2-8 Asynchronous Transfer Mode (ATM) Layer 2-8

ATM is Cell-based 2-8 AT M i s Service Transparent 2-9 AT M is Connection-oriented 2-9

Switched Virtual Circuits (SVCs) 2-12 Permanent Virtual Ci rcuits (PVCs) 2-12

ATM Interfaces 2-12

Interim Local Man agem ent Interface ( ILMI) 2-13 ATM Address Registration 2-13

The A TM Layer and Cell Stru cture 2-14

Physical Layer 2-15

SONET STS-3c 2-15 SDH STM-1 2-15

IRTUAL

LAN C

ONCEPTS

What is a Virtual LAN (VLAN)? 3-1 Creating Inter-switch VLANs 3-1 Extending VLANs into the AT M N e tw o rk 3-2

UTTING YOUR

ATM N

ETWORK TOGETHER

Planning Your Network 4-1 ATM Configuration Rules 4-2 Extending VLANs Through the A TM Network 4-2 A TM Connections Within Your Network 4-3

ETWORK CONFIGURATION EXAMPLES

A TM Backbone in the Buildi ng 5-1 Campus Configuration 5-2 Making a Building Resilient to Network Failure 5-4

NSTALLING AND SETTING UP THE MODULE

Following Saf ety Information 6-1 Device Support 6-3 Pre-installation Procedure 6-3

Check the Power Supply 6-3

Installa tion 6-4

Connecting a cable to the ATM Port 6-5 Powering Up the Switch 6-5

Power On Sel f Test (POST) 6-5

Post-Installation Checks 6-5

LED Summary 6-6 Checking the Power Supply 6-7 Checking that the ATM Module is Installed Cor rectly 6-7 Checking the Physical Connections 6-7

CCESSING MANAGEMENT FEATURES

Screen Map 7-1 Keyboard Shortcuts 7-1 Correcting Text Entry 7-1

Logging On 7-3 Logging Off 7-4

Automatic Logout 7-4

ANAGING THE

ATM M

ODULE

Configuring an ATM Port 8-2 Extending VLANs into the AT M N e tw o rk 8-4

Displaying all VLANs 8-5 AT M Por t Setup 8-6 Mapping Far End MAC Addresses 8-8

Creating a MAC Addre ss to ATM Ent ry 8-9

Finding an Addre ss Entry 8-10

Updating Addres s Entries 8-10

Deleting an Address Entry 8-10 Displaying an ATM Connecti on 8-10

Finding an ATM Connectio n 8-11

Updating Addres s Entries 8-11 Setting Up Resilient Links 8-11 Upgrading Software 8-12

Error Messages 8-13

Status Messa ges 8-14

ONITORING THE

ATM M

ODULE

Statisti cs O verview 9-2 ATM Port Statistics 9-3 AT M VLAN LEC Status 9-5 AT M Physical Layer Statistics 9-10

Using Physical Layer Statistics to Troubleshoot 9-12

AFETY INFORMATION

Safety Notices A-1

World Trade Safety Information A-1

CREEN ACCESS RIGHTS

ATM M

ODULE TECHNICAL SPECIFICATIONS

Environm ental Specifications C-1 ATM Cable Specification C-1

Does the Cable Provide Sufficient Bandwidth? C-2

ROUBL ESHOOTING

How to Use this Guide to Troubleshoot D -1 Using LEDs D-2 Identifying the Problem D-3

ELAN Configuration Problems D-15

Solving Known Problems D-17

Power Supply Problems D-18 Power On Self Test (POST) Failure D-19 Cable Connection Problems D-20 ATM Problems D-21 VLAN or ELAN Problems D-22

Cleaning Dirty Fiber Optic Connectors D-24

ECHNICAL SUPPORT AND SERVICE

Electr onic Support E-1

WWW E-1 FTP E-1 IBM Bulletin Board System E-1

Vo ice Support E-1

OTICES

, T

RADEMARKS, AND WARRANTIES

T rademarks F-1 Statement of Limited Warranty F-2

Production Status F-2 The IBM Warranty for Machines F-2 Warranty Service F-3 Exten t of Warr a nt y F -3 Limitation of Liability F-4

Electronic Emission Notices F-5

Federal Communications Commission (FCC) Statement

F-5

Canadian Department of Comm unications (DOC)

Compliance Statement F-5

Avis de confor mite aux normes du ministere des

Communications du Canada F-5 European Union (EU) Statement F-6 Japanese Voluntary Control Council for Inter ference

(VCCI) Statement Class B F-7 Korean Communications Statement F-7 Information To The User F-7

LOSSARY

IBLIOGRAPHY

Asynchronous Transfer Mode (ATM) 1 LAN Emulation (LANE) 1

NDEX

BOUT THIS

UIDE

Introduction

This guide provides the information that you need to install and configure the IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module (agent software version 1.05) within an IBM 8271 Nways Ethernet LAN switch which has version 3.1 agent software installed.

This guide is intended for use by network administrators who are responsible for installing and setting up networking equipment. It assumes a basic working knowledge of Local Area Networks.

This guide explai ns Asynchronous Transfer Mode (ATM) and LAN Emulatio n (LANE) concepts, and provides a Bibliography for further reading.

The Release Notes shipped with the ATM Module may contain information that updates or overrides information in this guide. You should always follow the informa t ion in t he Rel ea se N ot es if it is dif f e rent from the information given in this guide.

Terminology

In this User’ s Guide the term ATM Module is used when referring to the IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module.

The device into which the ATM Module is fitted, is known simply as the Switch. An example of a Switch is the IBM 8271 Nways Ethernet LAN Switch Model 624.

This type of Switch is often referred to as an edge-device, edge-switch or boundary switch.

The term ATM S witch is used to identify the ATM device to which the edge-switch is connected.

Switches in IBM’s 8271 Nways Ether net LAN Switc h device range provide support for the ATM Module.

ATM Terminology

This user guide uses the term Network-To-Network Interface (NNI). You may know this protocol by its

alternative name, Network-to-Node Interface (NNI). Additional ATM definitions can be found in the Glossary at the end of this guide.

2 A

BOUT THIS GUIDE

Finding Information in This Guide

The following table shows you where to find specific information within this guide.

Convent ions

Table 1 and Table 2 list conventions that are used throughout this guide.

Task Location

Learning concepts

Chapter 1, ‘Features and Benefits” Chapter 2, ‘Network Layer Concepts” Chapter 3, ‘Virtual LAN Concepts”

Planning your network

Chapter 1, ‘Features and Benefits” Chapter 4, ‘Putting Your ATM Network Together” Chapter 5, ‘Network Configuration Examples” Appendix C, ‘ATM Module T echnical Specifications”

Upgrading Software

Chapter 8, ‘Managing the ATM Module”

Installing the A TM Mo dule

Chapter 6, ‘Installing and Setting Up the Module” Appendix A, ‘Safety Information”

Accessing screens Chapter 7, ‘Accessing Management Features”

Appendix B, ‘Screen Access Rights”

Managing the ATM Module

Chapter 8, ‘Managing the ATM Module”

Monitoring the ATM Module

Chap ter 9, ‘Monit oring t he ATM Modu le”

Troubleshooting Appendix D, ‘Troubleshooting” Getting Technical

Support

Appendix E, ‘Technical Support and Service”

Identifying terms ‘Glossary” Further reading ‘Bibliography”

Table 1

Notice Icons

Icon Notice Type Alerts you to...

Information note

Important features or instructions

ATTENTION Risk of system damage or data loss

CAUTION Conditions or procedures that can cause

personal injury that is neither lethal nor extremely hazardous

DANGER Conditions or proce dures that can result in

death or severe personal injury

Table 2

Text Conventions

Convention Description

Screen display

This typeface represents information as it appears on the screen.

The words “Enter” and “Type”

The word “enter” means type something and then press the Retu rn or En ter k ey. Do not press the Return or Enter key when an instruction simply says “type.”

[Key] names Key names appear in text in one of two ways:

■

Referred to by their labels, such as “the Return key” or “the Escape key”.

■

Enclosed within brackets, such as [Return] or [Esc].

If you must press two or more keys simultaneously, the key names are linked with a plus sign (+). For example: Press [Ctrl]+[Alt]+[Del].

Related Documentation

The ATM OC-3c Module documetation set includes:

■

IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module Quick Reference Guide.

Part Number 02L1333

■

IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module Release Notes.

Part Number 02L1334

Words in

Italics

Italics emphasize a point or denote new terms at the place where they are defined in the text.

Words in

bold

Bold text denotes key features.

Table 2

Text C onventions (continued)

Convention Description

4 A

BOUT THIS GUIDE

EATURES AND

ENEFITS

This chapter describes the main features of the IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module and the benefits of ATM within your network.

The ATM Module provides a high-speed ATM connection between your IBM 8271 Nways Etherne t LAN Switch and the ATM network.

Positioned within a workgroup or departmental LAN, the A TM Module p ro vides a fas t ATM downlink to the building or ATM campus.

Resilient links protect your Switch from network and equipment failure, while the software upgrade feature future-proofs your Switch by allowing you to add new features as they become available.

Additional featur es ar e provided by the Switch, and you should refer to the guide that accompanies y our Switch for mor e details. The Release Notes that accompany the ATM Module list the IBM 8271 Nways Ethernet LAN Switches that support the ATM Module.

ATM Benefits

ATM is the only technology specifically designed to carry voice, video and data traffic simultaneously and to provide the required level of service that these different applications need in order to run effectively across a network. ATM provides the following benefits:

■

It is easy and low cost to add additional services to the ATM network.

■

Services can be added as and when they are needed. It is easier to scale ATM networks compared to other network technologies.

■

ATM devices interoperate with your existing network. LAN Emulation (LANE) is a standards based technology specifically designed to provide interoperability between existing Ethernet/Fast Ethernet networks and ATM networks. LANE allows users to interoperate with ATM or traditional LAN based servers over ATM for higher performance and functionality.

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EATURES AND BENEFITS

ATM Module Features

The following list summarizes the ATM Module featu re s . These feat u res are d escrib ed in more detail in this guide.

■

Conforms to ATM Forum Standards

■

OC-3c 155Mbps Interface

■

SONET (STS 3c) and SDH (STM-1) compliant

■

Multi-mode Fiber, SC connectors

■

LAN Emulation (LANE)

version 1.0

■

16 Emulated LAN Clients

■

512 Virtual Circuits

■

1024 remote MAC Addresses

■

User -To-Network Interf ace (UN I)

version 3.0 and 3.1

■

Interim Local Management Interface (ILMI)

■

AAL5 ATM Adaptation Layer

■

16 Virtual LANs (VLANs)

■

RMON per Em ul ate d L AN. R MON Gr ou ps su pp ort e d:

■

Alarms

■

Events

■

Statistics

■

History

■

Data buffer to store 40,000 ATM cells

■

High performance with fast data transfer

■

Wire Rate Transmission

on ATM port

■

Low Latency (68 microseconds when using Store and Forward traffic management between ATM and Ethernet components)

■

Resilient Links protect your network against cable and equipment failure

■

SNMP management

■

Telnet and local management (using VT100 screens)

Cabling and environmental specifications are listed in Appendix C, ‘ATM Module Technical Specifications”.

ETWORK LAYER

ONCEPTS

This guide contains several chapters that describe the basic concepts behind ATM technology, and integrating ATM into your existing network:

■

This chapter describes some of the concepts behind the network layer architecture of a typical AT M network.

■

Chapter 3, “Virtual LAN Concepts” describes how Virtual LANs (VLANs) are extended into the ATM network.

■

Chapter 4, “Putting Y our ATM Network Together” describes how to plan your ATM network.

■

Chapter 5, “Network Configuration Examples” provides some examples of how you can use the AT M Module within an ATM networks.

If you are already familiar with these concepts, refer to Chapter 6, “Installing and Setting Up the Module”.

If you have read the concepts chapters and still requir e a more in-depth explan ati on , refer to the technical publications listed in the Bibliography.

The Layered Network Architecture

Asynchronous Transfer Mode (ATM) is on ly part of a layered net wo rk arch ite ct u re. Th is ar chit e c ture is shown in Figure 2-1.

Each of the layers in discussed in turn; starting with the Upper Layer and working down to the Physical Layer.

Figure 2-1

Network Layer Architecture

2-2 C

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2: N

ETWORK LAYER CONCEPTS

Upper Layer Protocols

The

Upper Layer

is the layer in the network architecture that rel a tes to user applications and service requ ests. For example, an application could be fi l e transfer softwar e, and t he ser vic e reque st c ould be a req uest t o transfer a file from a user’s PC to a shared file server.

User data and control information is passed down the network layers in the source device, and passed up the layers at the destination device.

What is LAN Emulation (LANE)?

LAN Emulation (LANE)

allows users on Ethernet, Token Ring, and other traditional LAN networks, to communicate with each other over an ATM network.

LANE emulates the broadcast nature of traditional LANs. Each LANE broadcast domain is known as an

Emulated LAN (ELAN)

Each ELAN can only carry one type of traffic. For example, an ELAN could carry either Ethernet frames or Token Ring frames, but not both.

There can be several ELANs on a single ATM network. Some of these ELANs could be carrying Ethernet traffic and others could be carrying Token Ring traffic.

T raffic from one ELAN is not seen on another ELAN, as they are logically separate broadcast domains. If devices from different ELANs need to communicate with each other, t hey must do so using an ATM ro uter.

LAN emulation software is contained within ATM devices which can be added to your existing network.

LANE allows you to add ATM to your network without having to replace or upgrade the whole of your underlying technology. LANE allows you to do this because it is completely transparent to the ATM network and to the traditional LAN network, end-users, operating systems and applications.

LAN Emulation allows users on traditional LANs to communicate over ATM by performing the following tasks:

■

Emulates the broadcast nature of LANs.

■

Maps MAC addresses to ATM addresses.

■

Maps upper layer connection-less technologies to the

connection-oriented

ATM network.

Although LAN Emulation emulates a range of network technologies, all examples in this guide are be based on an Ethernet network.

What is LAN Emulation (LANE)? 2- 3

LAN Emulation Components

Each

Emulated LAN (ELAN)

is composed of a set of LAN Emulation components. This section describ es each of these components.

LAN Emulation Client (LEC)

Each ATM de v ic e has a number of LAN Emul at i on clients. Each

LAN Emulation Client (LEC)

is responsibl e for tak i ng Ethernet fr am e s and passing them through the ATM network to the LEC se rving the destination address. The dest ination LEC is r esponsible for re ceiving the frame from the ATM network and passing it to the local Ethernet network, where it can be delivered to the destination address.

LAN Emulation Server (LES)

Each

LAN Emulation Server (LES)

controls a single

Emulated LAN (ELAN)

. The purpose of the LES is to store address and control information for the ELAN it is serving, and to pass this information onto the clients and other components within the ELAN.

The LES, therefore, needs to know the address of every client and component in the ELAN.

Broadcast and Unknown Server (BUS)

Each ELAN has a

Broadcast and Unknown S erver (BU S)

. The BUS fo rward s frames that it receiv es fro m a n y client to all of the clients in the ELAN. The BUS is used to forward broadcast and multicast frames so that they are

flooded

throu ghout the ELAN . The BUS also

floods

unicast frames if the location of the destination MAC address is u nkn own.

LAN Emulation Configuration Ser ver (LECS)

The

LAN Emulation Configuration Server (LECS)

is an optional component, and is not essential for the normal running of an ELAN

The LECS stores the names of all th e ELA Ns that ha ve been set up on the ATM network, and the address of the

LAN Emulation Server (LES)

that serves each of

these ELANs. If there is an LECS on the network, any client can

interrogate the LECS to find the address of the server associated with the ELAN they wish to join. The clients may also get ELAN configuration information from the LECS.

If a LECS is not present on the A TM network, the server addres s to be used by the clie nt must be specif ied using the management software on that client’s ATM d evice.

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ETWORK LAYER CONCEPTS

LAN Emulation Components in Your Network

Each Emulated LAN consists of a single

LANE Service

and a number of LAN Emulation clients. A LANE Service consists of:

■

LAN Emulation Server (LES)

■

Broadcast and Unknown Server (BUS)

■

Optional

LAN Emulation Configuration Server (LECS)

Figure 2-2 shows a logical view of a typical ELAN.

Figure2-2

LAN Emulation Components

The router shown in Figure 2-2 is not a LAN Emulation component, but would be required should a device on one Emulated LAN need to communicate with a device on another Emulated LAN.

You may wish to have more than one LECS on your network for security reasons. For example, you may wish the Finance department to be controlled by one LECS and the rest of your network to be controlled by a different LECS.

LAN Emulation and IBM Devices

LAN Emulation components are implemented in ATM dev ic e s . The L A N Emulatio n standards ( re f erence d i n the Bibliography) do not specify how each vendor implements each of these components.

What is LAN Emulation (LANE)? 2- 5

Joining the ELAN

Before a LAN Emulation Client (LEC) can transmit any Ethernet frames onto the ATM network it must first join an ELAN . To join the ELAN:

The LEC must know the name of the ELAN it is to join.

The ELAN name is specified through the management software on the Switch.

The LEC must communicate with the LAN Emulation Server (LES) that is serving that ELAN.

To communicate with the LES, the LEC must first locate the LES. The LEC can find the ATM address of the LES in one of the following ways:

■

If there is a LAN Emulation Configuration Server (LECS) on the networ k, the LE C gets the ad dr ess of the LES from the LECS.

The way in which the LECS determines which LES the LEC needs to communicate with, depends on the

policy

that the LECS is running. Refer to the user guide that accompanies your LECS for more details of the policies your LECS uses.

■

If the network does not have a LECS, the LEC gets the LES address from the management software on the ATM device.

The LEC must have a connection to the Broadcast and Unknown Server (BUS).

When the LEC has joined the LES, the LES helps the LEC locate the

Broadcast and Unknown Server

(BUS)

associated with that ELAN.

Locating the LECS

Before the LEC can ask the LECS for the address of the LES, the LEC must first locate the LECS. There are three ways i n w h ich th e LEC can locat e the LECS, and the LEC tries these methods in the following order:

■

The LEC can ask the adjacent ATM Switch using the

Interim Local Management Interface (ILMI)

■

The LEC can use a well known ATM addr es s that is reserved for the LECS. The well known address is pre-programmed into most LECS devices. The well known address is:

47007900000000000000000000:00A 03E000001:00

■

The LEC can use a reserved

Permanent Virtual

Circuit (PVC)

which the ATM Switch has already routed to the LECS. The reserved PVC is VPI 0, VCI 17.

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ETWORK LAYER CONCEPTS

Mapping Ethernet and ATM Addresses

Each device connected to an Ethernet port has one or more MAC addresses.

Each ATM device has a number of LAN Emulation clients, and each

LAN Emulation Client (LEC)

has an

A TM address . A n exa mpl e of t hi s i s s how n in F i gur e2-3.

Figure2-3

LAN Emulation Clients and Ethernet Hosts

These clients represent (act as a proxy) for devices connected to the Ethernet ports.

Whenever an Ethernet device wants to communicate with another device over the ATM network, the LEC must first discover the ATM address of the LEC that is acting as a proxy for the destination MAC address. The LEC must do this for each unicast Ethernet fram e sent. The process is known as

Address Resolution.

Address Resolution

The process by which a LEC associates a LAN destination address with the ATM address of another LEC (or the BUS) is known as

Address Resolution

Each LEC keeps a LAN Emulation

ARP Table

(which should not to be confused with the IP ARP Table). The ARP T able lists the remote destination MAC addresses and the ATM address of the LEC though which each destination MAC address can be reached.

Prior to sending a frame with a known destination, the LEC checks th e ARP Table to s ee if the dest inati on MAC address of the frame is listed in the ARP Table. The action the LEC then takes depends on whether the MAC address is listed in the ARP Table:

■

If the destination MAC address is listed in the ARP Table:

■

and there is an A TM connection to that LEC, the frame is sent directly to that LEC.

■

and an ATM connection has not already been set up, the LEC sets up an ATM connection.

■

If the destination MAC address is not listed in the ARP Table

, the LEC sends the frame to the BUS. The BUS then sends the frame to all LECs on the Emulated LAN.

Sending a frame to every LEC is an inefficient use of resources, so the LEC also tries to locate the MAC address for future use.

To discover the correct address, the LEC uses a process called

LAN Emulation Address Resolution

Protocol (LE_ARP)

What is LAN Emulation (LANE)? 2- 7

LAN Emulation Address Resolution Protocol (LE_ARP)

An LE_ARP request is sent to the LES to locate the destination MAC address. The LES in turn sends the LE_ARP request to all of the LECs in the E mulated LAN.

LECs represent (act as a proxy) for MAC address devices connected to the Ethernet ports. When a LEC receives an LE_ARP request it checks whether the MAC address is on its Switch. It does this by checking the entries in the Switch database.

If the MAC address belongs to one of the devices connected to an Ethernet port, the LEC sends an LE_ARP response to the LEC that sent the original LE_ARP request.

The LEC that sent the LE_ARP request adds this information to its ARP Table. The LEC then sets up a direct connection through the ATM network to the appropriate LEC, so that subsequent frames are forwarded more efficiently.

What Happens to Unicast Frames?

The path a unicast frame takes through the ATM network depends on whether the location of the destination address is known to the sending LEC.

■

If the location of the destination address is known

, the LEC sets up a direct connection to the

LEC serving the destination address.

■

If the location of the destination address is unknown

, a unicast frame is sent to the

Broadcast

and Unknown Server (BUS)

; where it is treated in

the same way as a broadcast or multicast frame.

In addition the sending LEC attempts to locate the LEC serving the destination address. It does this using the LE_ARP process, described in “LAN Emulation Address Resolution Protocol (LE_ARP)”.

What Happens to Broadcast and Multicast Frames?

Each

Emulated LAN (ELAN)

acts as a broadcast domain. When a broadcast or multicast frame is passed to the LEC for transmission, the frame is sent to the

Broadcast and Unknown Server (BUS)

When the LEC receives a broadc as t, mul tic as t, or unicast frame it checks to see if it originally sent the frame, and then does the following:

■

If the LEC sent the frame, it discards the frame.

■

If the LEC did not send the frame, the LEC passes the frame to the Ethernet device so that it can be forwarded to the appropriate port(s).

Unlike broadcast and multicast frames, the number of unicast frames that can be sent to the BUS every second is limited so as not to overload the BUS and LECs with too much traffic.

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ETWORK LAYER CONCEPTS

ATM Adaptation Layer (AAL)

Ethernet frames can be between 64 and 1514 bytes in length. ATM transmits data in fixed length

cells

Each cell contains 48 bytes of user data. The

ATM

Adaptation Layer (AAL)

converts data between the

Ethernet and A TM formats. The AAL has a

Segmentation and Reassemb ly (SAR)

sub-layer that does the conversion. In the sending device the LEC passes the Ethernet

frames to the SAR. The SAR converts the user data into fixed length cells, and passes these cells to the ATM Layer for transmission across the ATM network.

In the receiving device, the SAR converts the ATM cells back into the appropriate user data again, and passes this data to the LEC.

As ATM can carry different traffic types (for example, voice, video, and other data), several Adaptation Layer protocols have been defined. These protocols operate simultaneously within the Adaptation Layer, and allow the ATM Layer to support different applications and traffic types.

The IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module uses the AAL5 ATM Adaptation Layer protocol, which is a data-oriented protocol. The ATM Module will only work with other AAL5 devices.

Asynchronous Transfer Mode (ATM) Layer

Asynchronous Transfer Mode (ATM)

is a connectionoriented transmission protocol that has the following features:

■

ATM us es the

Signalling Protocol (Q.2931)

to dynamically create, maint ain and clear ATM connections between end-systems.

■

ATM uses fixed length packets known as

cells

, and

each cell identifies the connection to be used.

■

ATM is transparen t to the m ul t ip l e se rv i ces it supports and c a n c arry cells f rom diffe rent applications over the same physical connection.

■

ATM has well-defined user and network interfaces.

ATM is Cell-based

ATM uses fixed length packets called

cells

. The first

five bytes of the cell is the

cell header

. The cell he ader contains the information necessary to deliver the cell to the correct destination.

Fixed-length cells offer smaller and more predictable switchin g d e la ys, be ca u se ce ll switching is le ss complex than variable-length packet switching.

Having all the data in the same cell format also dramatically increases the speed of transmission, by eliminating the need for protocol recognition and decoding. A good analogy is containerized shipping, where uniform shape and weight containers with standardized labelling, ease and speed up processing.

Asynchronous Transfer Mode (ATM) Layer 2-9

ATM is Service Transparent

ATM allows for the high speed transfer of a wide range of user traffic, inc l uding voice, v ideo and other da ta.

The cell format means that more than one service (traffic type) can be

multip lexed

over the same

physical line, see Figure 2-4.

Figure2-4

Service Processing

Cells ar e

de-multiplexed

at the other end of the connection and forwarded to the correct service destination.

Multi-service processing promotes scalability by significantly reducing the number of changes needed to add new service traffic types to your network.

ATM is Connection-oriented

ATM is a

connection-oriented

transport service that requires a communication channel to be set up between the ATM source and destination end-systems before ATM cells can pass between them.

Before a direct data connection can be set up between two end-systems, a number of control connections are set up. These control connections are beyond the scope of this guide. If you require further information about control connections, refer to the ATM Forum’s “LAN Emulation Over ATM” document.

Figure 2-5 shows the logical structure of a communication channel.

Figure 2-5

Communication Channels

Several communication channels can operate over the same physical link. Each

Virtual Path Connection (VPC)

contains several communication channels known as

Virtual Channel Connections (VCCs)

The ATM Module only manages Virtual Channel Connections (VCC).

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A VCC is defined as spanning end-to-end, whereas a

Virtual Channel (VC)

is the name given to a section of

the VCC, refer to Figure 2-6.

Figure2-6

Connection Terminology

Many virtual channels can exist on the same physical link. Each virtual channel is identi fie d by a pair of numbers:

■

The

Virtual Path Identifier (VPI)

and

■

The

Virtual Channel Identifier (VCI)

Any end-system that wishes to communicate with another end-system must first use the

Signalling

protocol to set up the VCC. The

Signalling

protocol negotiates with each ATM device between the end-systems to set up a series of virtual channels. Each of these virtual channels is identified u sing the VPI and VCI values.

Figure 2-7 on page 2-11 shows how ATM cells are switched through the A TM network using the VPI/VCI values.

Instead of containing the ATM address of the final destination device, each cell header contains the VPI/VCI values associated with the virtual channel it is going to take to get to the next ATM Switch in the connection.

Each ATM switch kno w s th at when it r eceives a cel l with a particular VPI/VCI value on one port that it must transmit the cell on another port with another VPI/VCI.

Cells are switched through the network based on these VPI/ VC I va lues, and swit c hin g is p e rf o rme d independently for every cell. Each cell can be thought of as taking a virtual channel connection.

The VPI/VCI values are only meaningful in the c onte xt of that user-to-switch, or switch-to-switch, interface. Identica l VP I/ VCI values ca n e xist on differ e nt interfaces within the network.

Connections t ha t ar e e stabl ishe d d ynamica lly usi ng the Signalling protocol are known as

Switched Virtual

Circuits (SVCs). Switche d V irtual C i rc uits

are described

in “Switched Vir tual Circu i ts (SVCs)” on pa ge 2-12. ATM connections can also be established via

management, and these type of connections are known as

Permanent Virtual Circuits (PVCs)

Permanent Virtual Circuits

are described in

“Permanent Virtual Circuits (PVCs)” on page 2-12.

Asynchronous Transfer Mode (ATM) Layer 2-11

Figure2-7

Switching Cells using VPI and VCI values.

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Switched Virtual Circuits (SVCs)

SVCs use the signalling protocol to dynamically define connections as they are needed and to release them when they are no longer needed.

SVCs use signalling for:

■

Connections initiated by the user/application.

■

Connections established and dropped dynamically.

■

Varied connection time.

■

Connections not automatically re-established after network failure.

Permanent Virtual Circuits (PVCs)

The most basic connection setup requires the definition of each connection via management. These type of connections generally remain established for long periods of time.

PVC attributes include:

■

Connections initiated by network management.

■

Long-term connection duration.

■

Automatically re-established after network failure.

■

Supported by MIB or other management entity.

The ATM Module does not support PVCs.

ATM Interfaces

ATM technology is implemented in A TM edge-devices and ATM Switches.

ATM provides a

User-to-Network I n terface

(UNI). The User-to-Netw o rk Interfac e (UNI) is us ed to con nect an ATM edge devic e to an ATM switch that is managed as part of the same network.

ATM al so provides a

Network-to-Network Interface (NNI)

that is typically used to interconnect two ATM switches managed as part of the same network.

The ATM Interfaces are shown in Figure 2-8.

Figure 2-8

ATM Interfaces

The User-to-Network Interface (UNI) is managed by the

Interim Loca l Management Interface (ILMI)

protocol.

Asynchronous Transfer Mode (ATM) Layer 2-13

Interim Local Management Interface (ILMI)

The ATM Forum produced the

Interim Local

Management Interface (ILMI)

to increase monitoring and diagnostic facilities, and to provide ATM address registration at the

User-to-Network Interface (UNI)

ILMI uses a

Management Information Base (MIB)

and

the

SNMP

protocol.

Each device that provides ILMI support contains a

UNI Management Entity (UME)

, which uses SNMP to access management information stored in the ILMI MIB of the adjacent switch, see Figure 2-9.

Figure2-9

UNI Management Enti ti es

ATM Address Registrati on

In order to establish an ATM connection, both the user and the network must know the ATM addresses used at that

User -to-Ne twork Int erfac e (UNI)

. An

example of an ATM address is shown below. 47007900000000000000000000:00A03E000001:00 An ATM address consists of three sections of

information and is 20 bytes in length:

network:host:identifier

Where

network

is a network prefix assigned to the

device by the ATM Switch, and is 13 bytes long. Where

host

is the edge-device identifier, and is 6

bytes long. Where

identifier

identifies the client within the

edge-device, and is 1 byte long. ILMI provides a mechanism for the edge-device (in

this case the ATM Module) to inform the ATM Sw i tch of the addresses it represents.

When the ATM Module initializes, the ATM Switch sends a network prefix to th e ATM Module. The ATM Module then tries to register itself with the ATM Switch by attaching the prefix to the front of its MAC address, and an identifier to the end of the address. It then sends this back to the A TM switch. If a cceptable, the ATM Switch registers the address as the ATM Module’s ATM address.

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The ATM Layer and Cell Structure

This section describes the cell structure, and how the ATM Layer uses the information stored in the cell header to perform each of its task s.

The ATM Layer’ s primary responsibility is to manage the sending and receiving of cells between the user and the network.

The A TM Layer acc ept s the user data and control information from the ATM Adaptation Layer , adds the cell header, and passes the resulting 53 byte cell to the physical layer.

In addition, it also receives cells from the physical layer, strips off the cell header and passes the remaining 48 bytes to the higher layer protocols.

The ATM cell has 48 bytes of payload (information to be carried) and five bytes of header information, making the cell 53 bytes in length.

The cell header contains the information used by the network to forward each cell to its destination. The AT M cell structure is shown in Figure 2-10.

Figure2-10

ATM Cell Structure

The ATM cell header consists of the following fields:

Generi c Flow Control (GFC)

— Provides local

functions, such as flow control over the

User- to Network I nterface (UNI)

. The valu e enco ded i n the GFC is not carried end-to-end and can be overwritten by the ATM Switch.

Virtual Path Identifier (VPI)

and

Virtual Channel

Identifier (VCI)

— The VPI/VCI values allow the network to associate a cell with a given connection, so that the cell can be switched to its destination.

Payload Type Identifier (PTI)

— The PTI is used to indicate whether the cell contains user information, or management information. The management information is used for resource and network congestion management.

Cell Loss Priority (CLP)

— The purpose of the

Cell

Loss Priority (CLP)

bit in the A TM cell is to i ndicate that cells with this bit set should be discarded before cells which do not have the CLP bit set. Cells can be discarded based on CLP condition and according to the network load. When the network overloads, a discard mechanism, based on the value of the CLP bit in the cell header, may come into operation.

Header Error Check (HEC)

— The HEC field is used for detecting bit errors in the cell header. It is also used for cell delineation, defining where the cell begins in a SONET frame.

Physical Layer 2-15

Physical Layer

The physical layer is responsible for transmitting and receiving ATM cells over a physical medium. It is also responsible for checking the integrity of the bits being transferred over a physical media, and for making sure that they are error-free.

The ATM Module is compliant with both

SONET STS-3c

and

SDH STM-1

physical layer standard s.

These standar d s ar e similar, and most devices allow you to use either framing standar d on each link in the AT M network.The same framing standard must be used at each end of the link.

Many users prefer to use the same framing st anda rd throughout the ir ne twork (f or example SONET STS-3c ).

The physical layer is sub-divided into:

■

Path

— SONET and SDH are capable of carrying traffic for a number of uppers layers, and ATM is only one of those layers. Each upper layer uses its own

Path

through the SONET/SDH layer.

■

Line

— A

line

is the whole path between one ATM device and the adjacent ATM switch or ATM end-station.

■

Section

— When ATM is used for telephone

networks, a

line

may cover a large distance, requiring optical repeaters to boost the signal along its way . The part of a

line

between an optical repeater and the adjacent repeater or switch is known as a

section

SONET STS-3c

Synchronous Optical N et w ork (SONET) is the phy sical layer most often associated with ATM. SONET provides, throug h a f raming struc ture, the mechanism for the transport of AT M c ells. Data c a n be transferred at

155.52Mbps.

SDH STM-1

SDH STM-1 is a physical layer similar to the SONET layer, but with some differences in frame fields. SDH STM-1 is the physical layer commonly used in Europe.

The physical layer and ATM layers in the network provide simple performance monitoring functions between ATM devices; providing basic information about the health of the link. These functions are known as “Operation and Maintenance (OAM)” functions.

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IRTUAL

LAN C

ONCEPTS

This chapter provides a brief overv i ew of Virt ual LAN (VLAN) concepts, and describes how to extend VLANs into the ATM network.

This user guide does not describe how to create or configure VLANs. VLAN configuration is described in the user guide that accompanies your Switch.

What is a Virtual LAN (VLAN)?

A V irtual LAN (VLAN) is a fle xibl e, loc ati on and t opolog y independent group of end-stati ons communicating as if they are on a common physical LAN.

You can create VLANs that closely correspond to how your network and business functions. For example, marketing personnel in different physical locations could be part of one VLAN and finance personnel could be in another VLAN.

VLANs provide the following benefits:

■

VLANs make mo ves an d cha nge s sim ple .

■

As each VLAN is a common broadcast domain, you can erect firewalls against broadcast storms.

■

VLANs improve security.

For a full description of VLAN functionality, refer to the user guide that accompanies your Switch.

Creating Inter-switch VLANs

You can create inter-switch VLANs using Virt ual LAN Trunks (VLTs ) on Fast Etherne t connec tions, as shown

in Figure 3-1.

Figure 3-1

Inter-sw itch VLANs

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Extending VLANs into the ATM Network

You can use LAN Emulation to define and extend VLANs seamlessly through the ATM network, as shown in the example in Figure 3-3.

Traffic from one

Emulated LAN (ELAN)

is not seen on another ELAN as they are logically separate domains. For this reason, when you plan your network, you should consider what ELANs you require, and how the VLANs will map to these ELANs.

The A T M Module has a LE C for each of th e Switch ’s 16 VLANS, and each VL A N/ L EC c an be mapped onto an

Emulated LAN (ELAN)

. In this way , E thernet traffic is mapped to an ELAN by a VLAN-to-LEC association. The mapping of VLANs to ELANs is shown in Figure 3-2.

When an Ethernet device attached to a Switch generates traffic, the Switch forwards the frames to the appropriate port.

A unicast frame is only forwarded to a port if the address of the destination device is known to be on that port and the destination port is in the same VLAN as the source port. If a unicast frame is forwarded to the ATM port, the ATM port uses the destination MAC addr es s to identify the ATM connection to use.

A broadcast or multicast frame is forwarded to all ports in the same VLAN as the source port. If a frame is received by the ATM port, the ATM port forwards i t to the BUS for the associated VLAN.

Figure 3-2

VLAN to ELAN M apping

Extending VLANs into the ATM Network 3-3

Figure3-3

Extending VLANs into the ATM Network.

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UTTING

OUR

ATM N

ETWORK TOGETHER

This chapter takes you through the process of planning your network. Topics include:

■

Planning and tracking your network configuration.

■

AT M Configuration Rules.

■

Extending Virtual LANs (VLANs) into the ATM network.

■

AT M connection types.

Planning Your Network

Before installing your ATM devices you shou ld spe nd some time planning your network structure. This section lists some of the points you should consider.

■

Are routes defin ed w it hi n y ou r ATM network so that your ATM devices can connect to your LAN Emulation services?

Examine your existing network topology and decide if further configuration is required. In particular , you should consider the location of your LAN Emulation services .

■

Does your existing ATM network have sufficient resources?

Consider the capacity of:

■

Your ATM Switc hes, and the num be r of additional c onnections yo ur ATM device requires.

■

Your LAN Emulation services, and the number of additional LAN Emulation Clients (LECs) your ATM edge-device will a ttempt to join.

■

Can your ATM devices communicate with each other?

■

Ensure that all of your ATM equipment is using the same line f ram in g and signallin g protocols.

■

Ensure that al l inter-switch routes ar e c onfig ur ed correctly.

■

How do you intend to manage the ATM network?

Can the network manager communicate with the ATM devices you wish to manage? Check the routing tables.

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■

Does your network meet s afety specifications?

You should always follow safety requirements and ensure that your device environment meets all technical specifications.

For the ATM Module these requirements are specified in Appendix A. For other devices, refer to the user guides that accompany those devices.

■

Does your networ k conform to the ATM configura t ion rules?

Make sure that your network meets the con figurati on rules described in “ATM Configuration Rules”.

ATM Conf igurati on Rule s

There are several things that you should consider before configuring your network:

■

Your cables and equipment must meet all of the tech nical specifications.

The ATM cable you connect to the ATM Module, must conform to the Multi-Mode Fiber (MMF-PMD) standard defined by ANSI x.3-166-1992.

3Com supports 62.5/125mm multi-mode fiber (MMF-PMD) cable. The maximum inter-s tation distance (including device- to-network connectors) should not exceed 2km (1.25 miles).

■

Allow for attenuation (weakening of sign al) when calculat i ng cable lengths.

■

Ensure that you have sufficient bandwidth.

Refer to Appendix C, “ATM Module Technical Specifica t ions” for more deta ils.

You cannot connect an IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module to another IBM 8271 Nways Ethernet LAN Switch ATM OC-3c Module; this is due to the signalling requirements used by ATM and LANE. There must be a standards-based ATM Switch between the two modules for them to operate correct ly.

Extending VLANs Through the ATM Network

When setting up VLANs and extending them into the ATM network you should consider the following:

■

What logical network domains, VLANs, do you wish to set up?

Traffic from one

Emulated LAN (ELAN)

will not be seen on another ELAN (unless a r outer i s used), as they are logically separate domains. For this r eas on you should consider:

■

What ELANs you require.

■

How the VLANs will map to the ELANs.

■

If you need to route between any of your ELANs.

■

Will you have sufficient ELAN resources?

When calculating the resources you require, you should consider the number of:

■

ELANs that your LAN Emulation services can support.

■

VLANs/ELANs th at ea ch edg e-dev ice ca n supp ort.

ATM Connections Within Your Network 4-3

■

Virtual circuits required.

■

MAC addresses that can be held in the device LAN Emulation ARP Table.

When a

LAN Emulation Client (LEC)

joins an ELAN, up to five control connections may be required before any data is transferr ed over a s eparate data connection (VCC). Each time a LEC connects to another LEC a further connection is required. You should keep this in mind when calculating the number of connections you require.

The ATM Module provides the following resources:

■

Up to 16 LECs to extend VLANs into the ATM network over ELANs.

■

512 Virtual Circuits to/from the ATM network.

■

1024 remote MAC Addresses.

The ATM Module supports only 16 LECs, but this does not limit your network to 16 ELANs.

■

Are the LAN Emulation services configured correctly?

Is the LAN Emulation service that the

LAN Emulation

Client (LEC)

is going to joi n configured corre c tly ?

For example, if your network uses a

LAN Emulation

Client Server (LECS)

, does the LECS know about the LES, and is the LES active? Have you supplied a valid ELAN name?

Configuring t he LECS and LES is outside of the scope of this user guide. C onsult the user guide that accompanies the device implementing the LECS or LES.

Alternatively, if your LEC will not be using a LECS and is being configured manually, ensure that:

■

The LES address that the LEC is using has been correctly entered via the local management screens.

■

The LES is active.

For the ATM Module, you can enter these settings using the Port Configuration screen described in “Displaying an ATM Connection”, on page 8-10.

ATM Connections Within Your Network

ATM connections in your ATM network can be established dynamically by the

Signalling

protocol

(

Switched Virtual Circui t

), or through management

(

Permanent Virtual Circuit

The ATM Module doe s no t sup port PVC connecti ons

. All A TM Module connections are SVCs. This network concepts section includes PVC configuration concepts for completeness.

■

Switched Virt ual Circuits (S VC)

— SVCs are set up dynamically by the signalling protocol. SVCs require very little configuration, and only use the resources you need. For these reasons, SVCs are commonly used in the LAN environment.

■

Permanent V i rtual Circuits (PVC)

— You may need to use a PVC within your network when a remote edge-device does not support

Switched

Virtual Circuits

. For example, remote edge-devices

Wide Area Networks (WANs)

often use PVCs.

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Figure 4-1 shows an example of a network configuration where a remote edge-device does not support LAN Emulation based on SVCs (it only supports PVC LAN Emulation).

Figure4-1

SVC Signalling Not Supported in Remote Edge-device

ETWORK

ONFIGURATION EXAMPLES

This chapter provides examples of possible network configurations using the ATM Module. If you are unfamiliar with ATM, you should read this chapter in conjunction with Chapter 4, “Putting Your ATM Network Together”.

ATM Backbone in the Building

This section gives an example of an ATM backbone within a single building, as shown in Figure 5-1.

In this case, the Ethernet Switch on each floor is provided with a high speed (155Mbps) full duplex link to the backbone. Using ATM as a backbone technology removes bottlenecks by providing scalable bandwidth, low-latency, high-speed data switching.

Ethernet VLANs can be extended into the ATM network using Emulated LANs (ELANs). Et h erne t packets are then switched between Ethernet to ATM transparently.

As well as providing a fast switched backbone between Ethernet LANs, ATM equipped file servers and services may be directly attached to the ATM network; giving improved performance to the Ethernet desktop.

Further advantages are gained in multi-media applications, due to ATM’s built-in quality of service.

Figure 5-1

ATM Backbone in the Building

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Campus Configuratio n

The section gives an exampl e of A TM within a campus environment. The diagram shown in Figure 5 -2 on page 5-3 demonstrates a balance between cost and performance requirements.

Building A

shows how you can concentrate IBM 8721 Nways Ethernet LAN Switch Model 612 and 624 devices using an IBM 8271 Nways Ethern et LAN Switch Mod el 71 2 . All t raffi c in te r na l t o Building A is switched over Fast Ethernet. In addition, an ATM link to the campus backbone provides high speed access to remote services.

Building B

shows how you can configure a building in a cost efficient manner, while retaining connectivity to the campus ATM network.

Only one A TM Module is required to connect the IBM 8271 Nways Ethernet LAN Switch Model 624 and Switch Model 524 devices to the ATM network. This provides connectivity for 48 Ethernet ports t o t he ATM backbone.

Building C

shows you a building similar to Building A, but with additional campus-wide, high performance access to directly connected ATM servers.

Campus Configuration 5- 3

Figure5-2

Campus and Cost Sensitive Network

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Making a Building Resilient to Network Failure

You can build resilience into your building backbone as shown in Figure 5-3. The provision of resilient links protects your network against cable and network failure by using a main and a standby link. Should the main link fail, a standby link automatically takes over the function of the main link.

In this example, the ATM Module fiber link provides the main link in t he resil ie nt link p ai r, and the Fast Ethernet fiber or copper link acts as the standby link.

This configuration ensures that all devices have access to a high-speed backbone connection at all times.

Figure 5-3

Resilient Link Configuration

NSTALLING AND SETTING

THE

ODULE

Following Safety Information

ATTENTION: Only hold the ATM Module by the edges to avoid damage from static. Do not touch the top or bottom of the circuit board.

DANGER: Before installing or removing anycomponents of a device, or carrying out anymaintenance work, you must read the safety informationprovided in Appendix A, “Safety Information” of this guide.

Danger: Avant d’installer ou de retirer les composantsd’une unité, ou de procéder à une opération de maintenance,vous devez prendre connaissance des consignes de sécurité figurant à l'annexe A, “Consignes de sécurité” du présent manuel.

Achtung: Vor dem Installieren oder Entfernen von Komponenten einer Einheit, bzw. vor dem Ausführen von Wartungsarbeiten unbedingt die Sicherheitshinweise in A nh a ng A , “Sicherheitshinweise”, dieses Handbuchs lesen.

Gevaar! Alvorens een component van een apparaat te installeren of te verwijderen, of alvorens een onderhoudstaak uit te voeren, moet u de veiligheid srichtlijne n le ze n in Ap p e nd ix A, “Sa fe ty Information”, van deze handleiding.

Perigo: Antes de instalar ou remover qualquer componente de um dispositivo, ou executar qualquer trabalho de manutenção, você deve ler as informações sobre segurança fornecidas no Apêndice A, “Informaçõíes de Segurança” deste guia.

Fare: Læs sikkerhedsforskrifterne i tillæg A, “SafetyInformation”, i denne vejledning, inden du installerer ellerafmonterer en enheds komponenter eller udfører vedligeholdelsesopgaver.

Gevaar: Voordat u onderhoudswerk uitvoertof componenten van een apparaat installeert of verwijdert,dient u eerst de veiligheidsvoorschriften te lezen in Appendix A, “Safety Information” van deze handleiding.

Pericolo: Prima di installare o di rimuovere qualunque componente di un dispositivo e prima di eseguire qualunque intervento di manutenzione, bisogna leggere le inf or m az ion i relative alla sicu rez za fornite nell'Appendice A di questaguida.

Fare: Før du installerer eller fjerner komponenter i en enhet eller utfører vedlikeholdsarbeid, må du lese sikkerhetsinformasjone n i Appendix A, “Safety Information” i denne boken.

Perigo: Antes de instalar ou remover qualquer componente de um dispositivo ou de executar

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NSTALLING AND SETTING UP THE MODULE

qualquer trabalho de manutenção, deve ler o conteúdo do Apêndice A, “Informações sobre Segurança”, deste manual.

Peligro:

Antes de instalar o extraer cualquiercomponente de un dispositivo, o realizar cualquier trabajo de mantenimiento, debe leer la información de seguridad incluída en el Apéndice, “Información de Seguridad” de esta guía.

FARA:

Lãs avsnittet “Safety Information” i Appendix A i det här dokumentet innan du utför underhållsarbete eller installerar/demonterar komponenter.

VAARA

: Ennen kuin asennat laitteeseen osia tai irrotat niitä siitä tai teet huoltotoimia, lue tämän julkaisun liitteessä A, “Safety Information”, olevat turvaohjeet.

ebezpečí:

řed instalací nebo odstraněním libovolné komponenty ze zařízen

ebo před prováděním údržby si musíte přečíst bezpečnostní

nformace z této publikace (Appendix A, "Safety Information").

Опасно:

Перед установкой или удалением какого-либо элемента устройства и проведением технического обслуживания необходимо ознакомиться с информацией по технике безопасности, приведенной в Приложении А, "Информация по технике безопасности".

Nebezpečenstvo:

Pred inštaláciou alebo odobratí ktorej koWvek jednotky, alebo inej práce spojene s daným zariadením, musíte si prečítaÝ bezpečnostné predpisy v Appendixe A, "Bezpečnostné predpisy" v tejto knihe.

Nevarnost !

Preden instalirate ali odstranite neko komponentno iz naprave ali kadar izvajate vzdrevalna dela, morate prebrati navodila za varno uporabo, navedena v Dodatku A " V arnostneinformacije" tega navodila.

Device Support 6-3

Device Support

The ATM Module allows you to connect your IBM 8271 Nways Ethernet LAN Switch to an ATM network. Switches that support the ATM Module are listed in the “Release Notes” that accompany your AT M Module.

Pre-installation Procedure

This section describes the procedures you need to perform before installing the ATM Module.

Check the Power Supply

Before installing the ATM Module ensure that you have sufficient power supply to power the Switch and ATM Module. Refer to the Release Notes for details about power supplies.

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Installation

This section describes how to install the ATM Module using the example of an IBM 8271 Nways Ethernet LAN Switch Model 624 device. Installation is similar for all devices compatible with this ATM Module.

If the Switch is connected to the network, turn off the power to the switch and disconnect the switch from the main power supply and the network.

Place the Switch on a flat, clean, hard, working surface.

Locate and remove the blanking plate which covers the ATM Module slot. Retain the blanking plate and the screws for future use.

Refer to the manual which accompanies your Switch to locate the slot where the ATM Module is located.

Use the guide rails within the Switch slot to align the ATM Module. The location of the guide rails and the correct positioning of the ATM Module is shown in Figure 6-1.

Slide the ATM Module into the slot without touching the top or bottom of the circuit board. Ensure that the module is pushed fully into the unit.

Use the thumb screws attached to the ATM Module to fix the module firmly into place.

Connect the Switch to the ATM network as described in “Connecting a cable to the AT M P ort” on page 6-5.

Power up the Switch as described in “Powering Up the Switch” on page 6-5

Follow the post-installation checks, as described in “Post-Installation Checks” on page 6-5.

Figure6-1

Fitting the ATM Module

Post-Installation Checks 6-5

Connecting a cable to the ATM Port

Ensure that the cable you wish to connect to the port meets the correct specificati on . For cable specifications, refer to “ATM Cable Specification” on page C-1.

Each end of the fiber cable has a transmit (Tx) and receive (Rx) connector. Connect the Rx connector to the port’s Tx socket. Connect the Tx connector to the port’s Rx socket. Do the same at the other end of the connection.

Powering Up the Switch

The Switch does not have an On/Off button, so the only way to power up the Switch is to connect it to the main power supply using a power cable.

Connecting a power supply and safety information is described in the user guide that accompanies your Switch.

Power On Self Test (POST)

When powered up, the Switch and ATM Module enter a

Power On Self Test (POST)

. The type of tests performed depend on how POST has been configured for the Switch. Two types of POST are availab le :

■

Normal POST

— a basic confidence check which takes between 10 and 20 seconds to compl ete, and includes:

■

Checksum tests of boot and system areas of

Flash

memory.

■

System memory tests.

■

MAC address verification test.

■

System timer test.

■

CAM (Contents Addressable Me mor y )

tests.

■

Console Port tests.

■

Internal packet forwarding tests.

■

Switch and ATM Module

ASIC (App lic ation

Specific Integrated Circuit)

tests.

■

Switch and ATM Module ASIC memory tests.

■

ATM Module interface tests.

■

ATM Module packet forwarding tests.

■

Extended POST

— more extensive testing which takes between 50 and 225 seconds to complete and includes all of the

Normal POST

tests plus more

extensive system memory and ASIC memory tests.

When a new Switch is powered-up for the first time, it performs a

Normal POST

, which is the default setting.

If you suspect that there is a problem with your device which has not been detected by the

Normal POST

, run

the

Extended POST

. Configuring POST is described in

the user guide that accompanies your Switch. The LEDs used to indicate POST failure and other

post-installation checks are described in “Post-Installation Checks”.

Post-Installation Checks

This section describes the LEDs and basic checks that you can use to verify your installation, and to ensure that the Switch and ATM Module are operating correctly.

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LED Summary

This section describes the LEDs that provide status and troubleshooting information. Table 6-1 lists the Switch LEDs, and Table 6-2 lists ATM Module LEDs.

Table 6-1

LEDs on the Switch

LED Name Color/State Indicates MGMT

(On the front of the Switch)

Green

Green flashing

Yellow

Yellow flashing

OFF

Switch and ATM Module are operating n ormally.

Switch or ATM Module is either downloading software or initializing, (which includes a

Power On Self Test

Switch has failed its

Power On Self

Test (POST)

ATM Module failed its

Power On Self

Test (POST)

No power to the Switch.

Module

(On the front of the Switch)

Green Green

flashing Green

(long on, short off)

Yellow

Yellow flashing

OFF

ATM port enabled; link present. ATM port disabled; link present.

This LED will flash until all configured LECs have successfully joined their ELANs.

ATM agent software is not installed correctly, or the ATM Module has failed its POST (if the MGMT LED is flashing yellow).

Switch has not recognized the ATM Module.

The A T M Module is n ot i nsta lled, or a link is not present on the ATM port, or the ATM Switc h is not on.

Table 6-2

LEDs on the ATM Module

LED Name Color/State Indicates Far End Status

(On ATM Module)

Green

OFF (and Link Status LED is Green)

OFF (and Link Status LED is OFF)

The ATM Switch has not detected an error on the ATM Module’s

transmit

link.

The ATM Switch at the far end of the con nection has detect ed a problem with the ATM Module’ s

transmit

connection , an d notified the A TM Module. For example, the

transmit

half of th e ATM Module’ s cable has been disconne cted at either the ATM Module e nd or ATM Switch end of the co nne ct io n.

The cable between the ATM Module and ATM Switch has been disconne cte d.

Link Status

(On ATM Module)

Green

OFF

A link i s prese nt on th e ATM port, and the port is receiving valid SONET frames.

The Link is not present on the ATM Port.

(On ATM Module)

Yellow

OFF

The ATM port is transmitting Ethernet, LANE, Signalling or control frames.

The ATM port is not transmitting cells.

(On ATM Module)

Yellow

OFF

The A TM p ort is r ec eivin g d ata cells.

The ATM port is not receiving incoming cells.

Post-Installation Checks 6-7

Checking the Power Supply

Check the MGMT LED on the Switch. If the MGMT LED is not lit there is a power supply problem. Try the following troubleshooting procedures:

Check that the power supply is plugged into the device, using a power outlet that is known to be working.

Check that the main power supply switch on the wall is set to the ON position.

Check and if necessary change the f use on the Switch or plug, and then power-up the Switch. Refer to the user guide that accompanies your Switch for details about fuses and safety instructions.

Replace the power cable with a cable known to be wor k ing, and pow er-up t he Swi tch.

Contact Technical Support. Refer to Appendix E.

Checking that the ATM Module is Installed Correctly

Power up the Switch and check that the Module LED (or Downlink Status LED) on the front of the Switch is lit green.

If the MGMT LED is not lit green, you should remove and then re-install the ATM module.

You can confir m th a t th e ATM Module is installed correctly b y accessing the lo cal management scr eens, as descr ibed in “Logging On” on page 7-3. If the ATM Module is in sta lled cor r ectl y, the ATM CONFIG URATION option appears in the Main Menu.

If the ATM CONFIGURATION option does not appear:

■

You may have an incompatible version of the software. Refer to the “Release Notes” for details of which version of the software should be downloaded.

■

It could be that the ATM Module is still initializing. If the ATM Module is still initializing, the MGMT LED flashes green.

Checking the Physical Connections

This section assumes that the ATM Module is correctly installed.

Check that the L ink Stat us an d Far End S tatus LEDs o n the ATM Module are lit green. If one or both of the LEDs is not lit, there is a problem with the physical connection. Follow the troubleshooting information below:

Ensure that both devices are powered-u p, and that the ports at both ends of the link are enabled.

Ensure that the cable is securely connected to the port at both ends of the link.

Check each end of the cable to ensure that each of the fiber connectors is correctly connected. If your cable connectors can be reversed, you may need to reverse the TX and RX cable connectors at one end of the link.

Some cable connectors have been designed so that they cannot be fitted incorrectly. Never use excessive force to connect cables.

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Remove any objects obstructing the cable and straighten out any kinks in the cable.

If you suspect that the fiber optic connector is dirty, refer to “Cleaning Dirty Fiber Optic Connectors” on page D-24.

Check that your cable meets the specifications described in “ATM Cable Specification” on page C-1.

Replace the cable, and check the Link Status LED again.

Contact IBM Technical Support; refer to Appendix E.

CCESSING

ANAGEMENT FEATURES

The menu-driven user interface bui lt into the de vice is known as the VT100 or Loca l Manageme n t interf ace. The VT100 management interface has a forms-based structure with pre-defined security levels, enabling access to be restricted to particular users.

Accessing and navigating the local screens is described in the manual which accompanies your IBM 8271 Nways Ethernet LAN switch.

Screen Map

Figure 7-1 on page 7-2 provides a map of available local management screens. The screens shaded gray appear when the ATM Module is installed. If these screens do not appear, your ATM Module is not installed co rrectly.

Keyboar d Sho rt cut s

There are several special characters or combinations of keyboard characters th at allo w you to navigate within the screens.

[Ctrl] + [K] displays a list of the available key strokes.

Correcting Text Entry

Use [Delete] on a VT100 terminal or [Backspace] on a PC. This moves the cursor one space to the left and deletes a character.

If you are using Telnet or a terminal emulation program you may find that some of the Control keys do not operate or that they activate other functions. Check carefully in the manual accompanying your Telnet or terminal emulation software before using the Control keys.

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Figure7-1

Screen Map

Logging On 7-3

Logging On

Connect your terminal to the Console port using a cross-over cable for a serial line connection.

At your terminal, press [Return] two or more times until the Main Banner is displayed, as shown in Figure 7-2.

Figure7-2

Main Banner

The Console port will automatically detect the line-speed (baud rate), and use the following default settings:

■

auto-baud

■

8 character size (data bits)

■

1 stop bit

■

no parity

Character size, stop bit, flow control, and parity values cannot be changed.

If your terminal is already setup with these values, the Main Banner will appear as soon as power-up is complete.

At the Main Banner, press [Return] to display the Logon screen, as shown in Figure 7-3.

Figure 7-3

Logon Screen

Type in your user name and password. Note that they are both case-sensitive:

■

If you are logging on for the first time (after installation or initialization), use a default user name and password to match your access requirements. We recommend that you use the default user

security

so that you can access all functions. The default users are shown in T able 7-1 on page 7-4.

■

If you have been assigned a user name, access level and password, type in these details.

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To find out which ATM screens can be accessed for each of the security levels, refer to Appendix B, “Screen Access Rights”.

For access rights to Switch scr eens, s ee the user guid e that accompanies your Switch.

When you have logged on, the Main Menu screen is displayed, as shown in Figure 7-4.

Logging Off

When you have finished using the facility, select the LOGOFF option from the bottom of the Main Menu. If you acce ssed t he fac ilit y us in g a Telnet session or modem, the connection will be closed automatically.

Figure 7-4

Main Screen

Automatic Logout

There is a built-in security timeout on the VT100 interface. If you do not press any keys for three minutes, a message warns you that the inactivity timer is about to expire. If you do not press a key within 10 seconds, the timer will expire and the screen will be loc ked ; an y d ispl ay e d st atistics will continue to be updated. When you next press any key, the display changes to the Auto Logout screen.

The Auto Logout screen asks you to enter your password again. If the password is correc tl y entered, the screen that was active when the timer expired is re-displayed. If you make a mistake entering your password, you are returned to the Logon screen.

Table 7-1

Default Users

User Na me Defaul t

Password

Access Level

monitor monitor monitor — this user can view, but

not change settings on the screens they can access.

manager manager manager — this user can view and

change the operational paramete rs (but not the special/security features) on the screens they can access.

security security security — this user can view and

change all manageable parameters on the screens they can access.

admin (no password) security — this user can view and

change all manageable parameters on the screens they can access.

ANAGING THE

ATM M

ODULE

This chapter describes how to manage the ATM Module. If you wish to view statistics, r efer to Chapter 9, “Monitoring the ATM Module”.

Figure 8-1 shows the screen map. Management features are shown in gray to help you locate the screen you need.

Figure8-1

Management Scr ee n Map

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Configuring a n ATM Port

The ATM Module Configuration Screen shows the settings and standards used by the ATM Module to communicate with other devices on the ATM network.

It is unlikely that you will need to change the value of these settings once they have been set.

ATTENTION: If you need to change the value of any of the settings, you may experience a temporary loss of communication while the device resets. If you do not need to make any changes, select the CANCEL button and not the OK button. Selecting the OK button resets the device.

The ATM Module Configuration screen can be accessed from the Main Menu or from the ATM Port Setup screen:

■

Select the ATM CONFIGURATION option from the Main Menu.

■

Alternatively, if you are already in the ATM Port Setup Screen, as described in “ATM Port Setup” on page 8-6, you can select the CONFIG button.

An example of the ATM Module Configuration screen is shown in Figure 8-2.

Figure 8-2

ATM Module Configuration Screen

Ensure that the A TM Mo dule and the ATM Switch it is connected to are set up to use the same signalling and SONET/SDH standards. The two devices should also use the same ILMI VCC and c ompatible values for MAX VPI Bits and MAX VCI Bits. If the devices do not use the same standards, they cannot communicate with each other.

The following fields are shown on the screen:

ATM Mode

Shows the

ATM Mode

of operation,

which is set to

LAN Emulation Version 1

. The

ATM

Mode

cannot be changed in this release.

Signalling

Specifies the

User-to-Network Interface (UNI)

Signalling

protocol used to communicate with other

devices. Select either

uni3.0

uni3.1

standards. The

default is

uni3.1

Configuring an ATM Port 8-3

SONET/SDH

Specifies the framing us ed. Selec t either

SONET STS-3c

SDH STM-1

. The d efau lt is

SONET

STS-3c.

The

MAX VPI Bits

and

MAX VCI Bits

fields described below, are used to determine how many bits can be used within each cell header to define the value of the VPI and VCI. The value of the VPI and VCI fields identify the connection.

MAX VPI Bits can be used to identify which WAN connection to use. If you have several remote sites (London, Manchester and Leeds) you can specify a unique VPI value which identifies traffic going to that site. For example, the VPI value for London could be = 1, Manchester could be = 2, and Leeds could be = 3.

There are 11 b i ts availab l e to b e s h ared between the VPI and VCI. The default is 3 VPI bits and 8 VCI bits. You should not normally need to change the defa ul t settings. The adjacent ATM Switch can read the settings of these fields via ILMI and normall y negotiates with the devices to use the lowest common denominator. If the ATM Switch is non-standar d, you may need to amend the

MAX VPI Bit s (0 –4 )

field.

MAX VPI Bits (0–4)

Shows the numb er of bi ts a vaila ble in the cell header that can be used to determine the value of the VPI. Up to 4 bits are available for use. The number of bits set offers a range of possible values for the VPI (as shown within Table 8-1).

Max VCI Bits

The number of bits available for the VCI is calculated aut omatically, using the foll o wing equation:

MAX VCI Bits = (11 minus the value of Max VPI Bits)

ILMI VCC

This number identifies the connection used

for

Interim L ocal Managem ent I nterf ace (I LMI)

requests.

The first field identifies the

Virtual Path

and the seco nd

field identifies the

Virtual Channel

Y ou should only change the ILMI VCC if the ATM switch connected to ATM Module does not use the default ILMI VCC (VPI = 0, VCI = 16).

VCC connections with values 0 (zero) to 31 are reserved for standard connections and you should avoid using these values wherever possible.

Hardware Version

Shows the version number of the

ATM Module hardware.

Table 8-1

VPI and Bit Settings

Desired Value of VPI Number of bits

required

00 0 or 1 1 within the range 0

–

within the range 0

–

7 3 (default)

within the range 0

–

15 4

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Upgradable Software Version

Shows the version number of agent software stored on the ATM Module (in

Flash EPROM

Boot Software Version

This is the version number

of the boot software stored on the ATM Module.

You should keep a copy of these version numbers, in case you need to contact IBM technical support.

ATM LEC SETUP

This button takes you to the ATM LEC Setup Screen (as shown in Figure 8-3) which allows you to extend VLANs into the ATM network.

Extending VLANs into the ATM Network

This section describes how to extend VLANs into the ATM networ k. T he ATM port can be in one or m ore VLANs. Each VLAN is associated with a LEC on the A TM Module, and each LEC is m a pped to an ATM E L AN.

There are two ways to access the ATM LEC Setup screen:

■

Select the ATM CONFIGURATION option from the Main Menu. The ATM Module Configuration screen is displayed, as shown in Figure 8-2 on page 8-2. Select the ATM LEC SETUP button.

■

Alternatively, if you are already in the ATM Port Setup Screen, as described in “ATM Port Setup” on page 8-6, you can select the CONFIG button to display the ATM Module Configuration screen. An example of the ATM Configuration screen is shown in Figure 8-2 on page 8-2. Select the ATM LEC SETUP button.

An example of the ATM LEC Setup screen is shown in Figure 8-3.

Figure 8-3

ATM LEC Setup Screen

Each time you complete the entry fields for a VLAN you must select APPLY to apply the changes. As soon as you select a different VLAN using the VLAN field any edits not already applied, using the APPLY button, are lost.

To set up an ATM VLAN:

Select the VLAN that you wish to c o nf igure. Enter the number associated with the VLAN in the designated field. VLAN to LEC mappings are shown in “ATM Port Setup” on page 8-6. The default VLAN is VLAN 1, the

admin

VLAN.

Y ou cannot configure VLAN 15 or VLAN 16 when these VLANs are being used for Auto-Select VLANs and Spanning Tree, respectively.

Extending VLANs into the ATM Network 8-5

If the VLAN is to be connected to an ELAN, select

Yes

. If you do not wish the VLAN to be connected to an ELAN, select No.

If there is a LECS cont ro lling ELANs on your network, it should automatically supply the LES address for the ELAN, and you should select the

LECS

option.

Only select the

Manual

option if:

■

A LECS is not in use on the network, or

■

The LECS is unaware of the existence of the ELAN to be joined, or

■

Y ou do not wish the LEC to join a LES controlled by a specific LECS.

Manual

is selected, the L ES addr ess field i s displ ayed on the screen, and you should enter the A TM address of the LES associated with the selected VLAN/ELAN.

Enter the name of the ELAN that the VLAN is to join. The ELAN must have already been set up in the ATM network and be operational.

Select the APPLY button.

If the LEC associated with the VLAN is activ e when APPLY is selected, it will te mporarily be co m e in a ctive while the changes are applied, and you may experience a brief loss of communication on that connection.

Displaying all VLANs

If you wish to display the VLAN membership for all ports on the Switch, complete the following steps. If you wish to configure VLANs for the ATM Module you should use the ATM VLAN Setup screen, as described in “Extending VLANs into the ATM Network” on page 8-4.

Select the SWITCH MANAGEMENT option from the Main Menu. The Switch Management screen is displayed, as shown in Figure 8 -4.

Figure 8-4

Switch Management Screen

For the

Management Level

field, select the

VLAN

option and press the [TAB] key. The scr een show n in Figure 8-5 on pag e 8-6 is displayed.

Select the SETUP button to display the VLAN Setup screen.

An example of the VLAN Setup screen is shown in Figure 8-6 on page 8-6.

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Figure8-5

VLAN Selected Screen

Figure8-6

Switch VLAN Setup Screen

Use [Ctrl]+[D] keys to scroll down the list box to view the rest of the list, including the ATM port.

The ATM port is shown as

ATM

in the

Type

field, or as

ATM Bp

if it has been set up as a backbone port.

ATM Port Setup

The ATM Port Setup screen allows you to switch the ATM port on or off, and provides status information about the state of the port, and the LECs associated with each of the VLANs. To display the screen:

From the Main Menu select SWITCH MANAGEMENT. The Switch Management screen is d isplayed, as shown in Figure 8 -4 on page 8-5.

For the

Management Level

field, select the

Port

option.

Ensure that the ATM port number is entered in the

Port ID

field. For example the ATM port is:

■

Port 13 on an IBM 8271 Nways Ethernet LAN Switch Model 612 and IBM 8271 Nways Ethernet LAN Switch Mod el 712

■

Port 25 on IBM 8271 Nways Ethernet LAN Switch Model 624 and IBM 8271 Nways Ethernet LAN Switch Model 524

Select the SETUP button to display ATM port setup information. An example of the ATM Po rt Setu p screen is shown in Figure 8-7 on page 8-7.

ATM Port Setup 8-7

Figure8-7

ATM Port Setup Screen

The screen shows the following field s :

Port

Identifies the selected port.

Port Speed

Shows the speed of the port connection.

Port State

Allows you to turn the port on and off. If you wish to allow traffic to pass through this port, select the

Enable

option. To prevent traffic passing

through the port, select

Disab le

Link State

Indicates whether the communication link connected to the port is capable of transmitting and receiving traffic. The states are:

Present

— the link is capable of transferring traffic; if

the ports are also turned on (

enabled

Not Available

— the link is not capable of transferring

traffic.

If the li nk is

Not Available

and both devices are powered-up and operational, there is a physical problem with your connection. For information about the cause of problems and possible solutions, see Table 8-2.

To transmit traffic the port must have a

Port State

Enabled

and the

Link State

must be

Present

Table 8-2

Link State Troubleshooting Summary

Problem Solution

The connectors at either end of the lin k have come loose, or been accidently pulled out.

Ensure that t he cable is securely connected to the port at both ends of the link.

The port at the far end of the link is

disabled

Enable the far end port.

If you have f iber ca ble with connectors that can be reversed; the two connectors at one end of the fiber cable may be plugged into the port the wrong way around.

Check that each cable connector is connected to the correct port socket. You may need to reverse the TX and RX cable co nnector s at one end of the link.

The cable is caught under a heavy object or become bent out of shape.

Remove any obstructions and straighte n out a ny kin ks i n t he cable.

The connector itself is physically damaged.

Contact your repair center for advice. Refer to Appendix E, “Technical Support and Service” for more deta ils.

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Lost Links

The number of times a link was unable to transmit traffic , that is, the number of times (si nce the device was reset) that the

Link State

became

Not

Available

LEC States

Shows the status of the LEC for each

VLAN. The state can be:

LEC Active

— traffic is passing through the LEC.

LEC Inacti ve

— traffic is not passing through the LEC.

LEC Not in Use

— you have decided not to connect this VLAN to t he ATM network. The VLAN may still be in operation within the Switch.

CONFIG

This button takes you to the ATM Module Configuration screen, which allows you to monitor and set the standards used by the ATM Module to communicate with other ATM devices. The ATM Module Configuration screen is described in “Configuring an ATM Port” on page 8-2.

ARP TABLE

This button takes you to the ARP Table screen, which allows you to displays the AT M and MAC addresses on remote devices. The ARP Table screen is described in “Mapping Far End MAC Addresses” on this page.

CONNECTI ON TABLE

This button takes you to the AT M Connection Table screen, which allows you to display AT M connection details. The ATM Connection T able is described in “Displaying an ATM Connection” on page 8-10.

Mapping Far End MAC Addresses

To communicate with a device, the software must be able to map the MAC address of the destination device to the destination edge-device’s ATM address.

This mapping is normally performed by the LEC, and for the vast majority of devices you do not need to map MAC addresses to ATM addresses.

The MAC address and ATM address mappings are stored in the LAN Emulation

ARP Table

(which should

not be confused with the IP ARP Table). To access the ATM ARP Table screen access the ATM

Port Setup screen, as described in “ATM Port Setup” on page 8-6, and then select the ARP TABLE button. An example of the ATM ARP Table screen is shown in Figure 8-8.

Figure 8-8

ATM ARP Table Screen

Mapping Far End MAC Addresses 8-9

VLAN

Allows you t o se lect a VL A N , an d displa y address information about remote systems connected to that VLAN.

Port

Identifies the selected port.

Far MAC Address

Shows the MAC Address on the

edge-device at the far end of the connection.

Far ATM Address

Shows the ATM Addres s for the LEC on the edge-device at the far end of the connection.

Type

The address entry can be:

Permanent

— The address entries are retained even if the device is reset or a power-off/on cycle occurs. All entries made through this screen are stored as Permanent entries.

Dynamic

— The address entries are aged out after a

set period of time.

Static

— The address entries are discarded when the

switch is reset. The following fields are used in conjunction with the

buttons at the bottom of the screen:

Far MAC Address

Allows you to type in the MAC

address of end-stations in the network.

Far ATM Address

Allows you to type in the ATM address of the far end LEC associated with the far end MAC address.

FIND A TM ADDRESS

This button allows you to l ocate

the A TM address mapped to a specifie d MAC address.

REFRESH

This button updates the view of the ARP

Table to include the latest available information.

INSERT

This button allows you to create a MAC

Address to ATM address mapping in the ARP T able.

DELETE

This button allows you to delete a MAC

address to ATM address mapping in the ARP Table.

Creating a MAC Address to ATM Entry

An easy way to edit an entry is to select a similar e ntry from the listbox using the spacebar. The far end ATM and MAC addresses of that entry are shown in the edit fields. You can then edit the addresses (without losing or changing the original entry) and select the INSERT button to create a new entry.

If you cannot select an entry in the listbox (because you are creating the first entry), use the following method:

In the

Far MAC Address

field, type in the MAC

address of the device to be added to the database.

In the

Far ATM Address

field, type in the far end ATM

address.

Select the INSERT button.

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Finding an Address Entry

In the

Far MAC Address

field, type in the MAC address associated with the ATM addr es s you are trying to locate.

Select the FIND ATM ADDRESS butt on. An asteris k (*) is shown next to the entry in the database listbox.

Updating Address Entries

To view up-to-date ARP Table entries, select the REFRESH button.

Deleting an Address Entry

Within the listbox, use the spacebar to select the entry you wish to delete.

Select the DELETE button.

Displaying an ATM Connection

This section describes how to create and view ATM connections in the ATM Connection Table.

To access the ATM Connection Table screen, access the A TM Port S etup s creen, as d escribed i n “ATM Port Setup” on page 8-6, and then select the CONNECTION TABLE but t on. An example of the ATM Connection T able screen is shown in Figure 8-9.

Figure 8-9

ATM Connection Table Screen

The following fields apply to the listbox:

Port

Identifies the selected port.

VPI:VCI

Identifies the ATM connection by showing

the Virtual Path Identifier and Virtual Circuit Identifier.

End

Identifies whether the near or far end LEC ATM

address is displayed. The options are:

Near

— the details are for the LEC in the A T M Module.

Far

— the details are f or the LEC at the far end of the connection, for example a LEC in an ATM Switch or attached ATM device.

Setting Up Resilient Links 8-11

ATM Address

Shows the ATM address of LEC for

either the ATM Module or the ATM Switch. If

Near

is shown in the

End

field, the address is the

address of the LEC in the ATM Module. If

Far

is shown in the

End

field, it is the add ress of the LEC in the AT M Switch or attached AT M devi c e at the far end of the connection.

Type

shows the connection type. The connection

types can be:

Incoming

— the switched virtual circuit was set up by

the Far End LEC.

Outgoing

— the switched virtual circuit was set up by

the Near End LEC.

Reserved

— a permanent virtual circuit has been set up.

VPI:VCI

Allows you to specify th e ATM connection by

typing in the

Virtual Path Identifier

and

Virtual Channel

Identifier

label s. Alt ernat ively, you can u se the sp ace bar

to select and copy a VPI:VCI entry from the listbox.

FIND ATM ADDRESS

This button allows you to find

an A TM Addr es s .

REFRESH

This button allows you to update the view

of ATM connection details.

Finding an ATM Connection

In the VPI:VCI field, type in the ATM Connection you wish to view.

Select the FIND ATM ADDRESS button.

Updating Address Entries

To view up-to-date ATM Connection Table details, select the REFRESH button.

Setting Up Resilient Links

You can protect a critical communication link against failure by ensuring that, should the main communication link fail, a standby duplicate communication link immediately and automatically take s over the task of the main link.

Each main and standby link pair is referred to as a

resilient li nk pair

■

If you wish to setup an ATM port as part of a resilient link, the other port in the resilient link must be a

Virtual LAN T runk

(a member of all

VLANs).

■

Typically the ATM Module port is paired with a Fast Ethernet port on the ATM Switch.

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Every 2 minutes the Switch checks the resilien t lin ks to ensure that the fastest link is the Main (active) link in the resilient link pair. If the fastest link is not the Main (acti ve ) lin k, th e Switch automa t ic a lly ma kes it the Main (active) link, on the condition that:

■

There have not been any

Lost Links

within the last 2 minutes on the faster link that will become the Main (acti ve ) link.

■

The faster link has been up for 2 minutes.

See the guide which accompanies your Switch for more details about setting up resilient links.

Upgradin g Sof tw are

The ATM Module has its own software which is upgraded independently of the Switch software.

You may ne ed to u p grade the softw are on the ATM Module or Swi tch if I BM produces a new version of the code, or if the existing code has somehow become corrupted.

The replacement software image must be held or placed on a local server which supports the

Trivial File Transfer Protocol (TFTP)

Select the SOFTWARE UPGRADE option from the Main Menu. An example of the Software Upgrade screen is shown in Figure 8-10.

Figure 8-10

Software Upgrade Screen

Complete the following fields:

Destination

Specify the type of device which you wish to receive the upgraded software. If you are upgrading the software on the ATM Module, select the ATM Module option.

File Name

Specify the name of the upgrade file held

on the server for this type of device.

Server Address

Specify the IP (or IPX) address of the

server holding the upgrade file.

If the upgrade is interrupted, due to a power failure for example, when the device powers up again, the MGMT LED is lit green and fla shes to i n dic ate that an upgrade is taking place, and the Module LED on the Switch is lit Yellow. The device attempts to download the last specified software image file.

Upgr adin g Sof twar e 8-13

When the OK button is selected, the status of the upgrade is displayed. The following error and status messages are avail ab l e:

Error Messages

This sectio n l i st s error messages th at may appear if an error occurs while downloading a new software image, and suggests solutions to the problem.

File Not Found

The file you require is not on the specified TF TP server. You need to specify a different TFTP serv er o r tran s fer the file you require to the correct directory on the TFTP server and try again.

Access Violation

You do not have access permissions to this file or director y. Ensure that the access permissions are changed.

Load server failed to respond

Communication with the TFTP server could not be established. Ensure that the workstation on which the TF TP server is set up is operating and that the network connection has been set up correctly.

The do w nload co uld not be star ted because of a lack of resources

Y ou are trying to download a file which requires more memory tha n is ava ila b le .

The record length differs from that implied by the value of the record length field.

The file you want to download may have been corrupted. You should obtain a valid file and try again.

The record type is not recognized

The file you want to download may have been corrupted, or is not the correct type of file for the selected device. You should obtain a valid file and try again.

Record checksum error

The file you want to download has been corrupted. In this case you should either retry with the current file, or obtain a valid file and try again.

The device type in the file is incorrect

The file you are trying to download is not suitable for the selected device. Ensure that you select either a different f ile or a dif fer ent devic e, befor e you try again.

The software image is not suitab le for this version of the hardware

The file you are trying to download is not suitable for the selected device. Ensure that you select either a different f ile or a dif fer ent devic e, befor e you try again.

Timeout

The operation to download the software failed after the operation timed-out. This may be due to a poor network connection, so try again.

If you see any other messages you should make a note of the message and contact your supplier.

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Status Messages

This section lists status messages that can appear when you download new software images to a device.

Active

The file is currently being downloaded to the selected device. Allow time for the download to complete.

Down load succ e ssful

The file you chose to download to the selected device was downloaded successfully.

Load Paused

The download failed and another attempt will be made. The download may have failed due to network re-configuration.

ONITORING THE

ATM M

ODULE

This chapter describes how to monitor the status and performance of your ATM Module.

Figure 9-1 shows the screen map. Monitoring screens are shaded gray to help you locate the screens you need.

Figure9-1

Status Monitoring Screen Map

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Statistics Overview

This section provi des a brief ove rview of the additi onal statistics that ar e available w hen you install an ATM Module. Refer to the user guide that accompanies the Switch for informat ion about the statistics that are provided by the Switch softwar e.

Table 9-1 groups the available statistics into logical categories, and tells you where each statistic is located.

ATM Module statistics screens are updated every 2 seconds to show the latest information.

Table 9-1

Statistics and Status Summary

Monitoring Use Backbone

To estimate the amount of traffic down the backbon e.

ATM Port Statistics screen:

■

Transmit Bandwidth Used

■

Receive Bandwidth Used

Physical Connection

To check that the physical connectio n is ope rational.

ATM Physical Layer Statistics screen:

■

Errored Seconds (Near)

■

Errored Seconds (Far)

■

Severe Errored Sec (Near)

■

Severe Errored Sec (Far)

■

Coding Violations (Near)

■

Coding Violations (Far)

■

Unavailable Seconds (Near)

■

Unavailable Seconds (Far)

ATM Port Statistics screen:

■

Receive Errors

VLAN/ELAN

To monitor the state of the LEC to LES set up process.

To monitor Ethernet traffic on the VLAN.

ATM VLAN LEC Stat us Screen:

■

LEC State

■

LEC ELAN Name

■

LEC ATM Address

■

Last LEC Failure Reason

■

LEC Operation at Failure

■

Fram es Received

■

Frames Transmitted

■

Octets Received

■

Octets Transmitted

ATM

To monitor ATM traffic.

ATM Port Statistics screen:

■

Cells Received

■

Cells Transmitted

■

Errored Cells

■

Bad VCC Received

AAL5

To monitor AAL5 traffic.

ATM Port Statistics screen:

■

Fram es Received

■

Frames Transmitted

■

Octets Received

■

Octets Transmitted

■

Errored Frames

■

Discarded Frames

Table 9-1

Statistics and Status Summary

Monitoring Use

ATM Port Statistics 9-3

ATM Port Statistics

The A TM Port Statistics screen provi d es a top level summary of traffic levels on the ATM Port. You can use the summary to estimate the amount of traffic on your network backbone, and to check the health of the incoming connection. Statistics are grouped into:

■

AT M Port Bandwidth use and incoming connection health.

■

AAL5 layer health and use.

■

ATM layer health and use.

To view the ATM Port statistics:

Select the SWITCH MANAGEMENT option from th e Main Menu. The Switch Management screen is displayed, as shown in Figure 9-2.

Figure9-2

Switch Management Screen

Enter the number of t he ATM port in the

Port ID

field.

Select the STATS b ut ton to display the ATM Port Statistics screen.

An example of the A TM Port Statistics scr een is shown in Figure 9-3.

Figure 9-3

ATM Port Statistics Screen

The figures shown for each statistic on this screen include ATM management traffic and normal Ethernet traffic.

The ATM Port Statistics screen displays the following fields:

Port ID

Identifies the currently selected port.

Transmit Bandwidth Used

Shows the percentage of available transmit bandwidth that is currently being used by transmit cells.

Receive Bandwid th U sed

Shows the percentage of available receive bandwidth that is currently being used by received cells.

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Receive Errors

Shows the percentage of cells received that have errors. For example, cells received with corrupted header information (

Header Error

Control – HEC

Receive Errors indicate that there is something wrong with the link, and you should check for the following faults:

■

Weak transmitter. Contact your supplier or Technical Support, as described in Appendix E.

■

The optic fiber cable is too long or does not meet other technical specifications. Check the cable against th e te ch nical spec ifica t io n given in Appendix C, “ATM Module Technical Specifications”.

■

The optic fiber connectors are dirty. To clean the connectors, follow the instructions given in “Cleaning Dirty Fiber Optic Connectors”, on page D-24.

■

If there is no traffic on the port, but there are Receive Errors, the SONET

Scramble

techniques on the ATM Module and ATM Switch are probably incompatible. Ensure that the SONET standards used are the same for the ATM Module and the ATM Switch.

The screen al so shows the AAL5 lay er sta tistic s. AA L is a set of protocols that translate user traffic from higher-layer applications/protocols into small, fixed size cells, and reassembles them into the higher level frame format at the destination device. The ATM Module supports AAL5. The screen shows the following AAL5 Layer statistics:

Frames Received

The number of frames received per second at the AAL5 interface for all traffic types (data and control).

Frames Transmitted

The number of frames transmitted per second at the AAL5 interface for all traffic types (data and control).

Errored Frames

The number of frames received that

contain an error.

Octets Received

The number of Ethernet octets

received at the AAL5 interface.

Octets Transmitted

The number of Ethernet octets

transmitted at the AAL5 interface.

Discarded Frames

The number of frames discarded

at the AAL5 interface due to lack of resources.

ATM VLAN LEC Status 9-5

The screen also shows the following ATM statisti cs:

Cells Receiv e d

The number of ATM cells received by

the port.

Cells Transmitted

The number of ATM cells

transmitted per second by the port.

Errored Cells

The number of ATM cells that contain

an error, for example, cells that have

Header Error

Control (HEC)

errors.

Bad VCC Received

The number of cells received where the specified connection is not recognized by the A TM Module (that is, the connection is not shown in the ATM Module Connection Table).

The following buttons are available on this screen:

CLEAR SCREEN COUNTERS

T o make it easier to note the changes in statistic values, you can use this button to reset the value of statistics shown on the screen to zero. Resetting the values shown on the screen does not reset the statistic values stored on this device.

LEC

This button takes you to the ATM VLAN LEC Status screen, w hich all ows you to monitor th e health of LECs and identifies the cause of any connection failures. The A TM VLAN LEC Status scr een is descr ibed in “ATM VLAN LEC Status” on this page.

PHYSICAL

This button takes y ou to the Physical L ayer Statistics Screen, which allows you to monitor the health of the physical connection, and is more useful in a WAN environment. The Physical Layer Statistics Screen is described in “ATM Physical Layer Statistics” on page 9-10.

ATM VLAN LEC Status

The A TM VLAN LE C Statu s scr een show s LEC stat isti cs for the ATM port. You can use the status information to monitor the health of a VLAN’s LEC and to track down the cause of any pr oblems. Y ou can also m onitor the amount of Ethernet traffic on the selected VLAN.

To access VLAN statistics, first access the ATM Port Statistics screen, as descri bed i n “ ATM Port Statistics” on page 9-3, and then select the LEC button.

An example of the ATM VLAN LEC Status screen is shown in Figure 9-4.

Figure 9-4

ATM VLAN LEC Status Screen

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Port ID

Identifies the currently selected port.

VLAN

Allows you to select the VLAN you wish to monitor. The default is VLAN 1. If you wish to review the state of all VLANs on the ATM Module, see “ATM Port Setup” on page 8-6.

LEC State

Shows the state of the LEC to LES

communication. The states are shown in Table 9-2.

LEC ELAN Name

Shows the name of the ELAN that

the VLAN/LE C ha s join e d.

LEC ATM Address

Shows the ATM Address of the

LEC associated with the selected VLAN.

Last LEC Failure Reason

If the LEC configuration fails, the last know failure st ate is show n. The fail ure state can be used to identify the cause of the failure. The failure state and possible causes are shown in Table 9-3.

Table 9-2

LEC State Summary

LEC State Description

Active The LEC is in use. Inactive The LEC is not in use. The LEC may be

inactive because it has not been able to establish communication with the LES and BUS, or because the ATM port has been disabled by management.

Not in Use You have specified that the LEC is not

required at the present time.

Table 9-3

Last LEC Failure Reason

State Possible Causes Possible Solutions None

The LEC is either inactive or has successfully completed the operation.

None required.

Timeout

A task could not be completed within its allotted time frame.

The s oftware has been set up to use a LECS, but a LECS is either not present on t he ne twork or broken.

The LES for th e EL AN is not functioning correctly

If there is a LECS on your network, ensure that it is operational and on part of the network that can be accessed by the ATM Module.

If a LECS is not present on the network, you must enter the LES Address for each ELAN manually using the A TM VLAN Setup Scr een (see “Extending VLA Ns into the ATM Network” on page 8-4).

Contact Technical Support.

Undefined Error

An error has occurred but no cause can be identified.

Unknown. Contact Technical

Support.

Version Not Supported

LANE 1.0 not supported.

The LANE services you are trying to connect to, do not support LANE version 1.0.

Ensure that the LANE Services use LAN E 1.0 .

(continued)

ATM VLAN LEC Status 9-7

Invalid Request Parameters

The LES/LE CS has rejected a requ est from the LEC because the request parameters were incompatible with the ELAN.

The LE C may b e requesting a resource that is on an ELAN which has a different LAN type to the LEC.

The frame size used could be wrong .

Check the underlying media for both the ELAN a nd the LEC requesting the service.

Check the frame sizes being used.

Duplicate LAN Destination

A destinatio n sour ce MAC add ress duplicates a previously registered MAC add ress.

The LES has received a request from a LEC which contains a MAC address already registered t o another LEC on the same ELAN.

You may have accide ntally en tered the same MAC addresses twice.

Ensu re that MAC addresses are unique.

Table 9-3

Last LEC Failure R eason

State Possible Cau ses Possible Solu ti o ns

Duplicated ATM Address

A source ATM addres s duplic a tes a previously registered ATM address.

The LES has received a request fr om a LEC which cont ains an ATM address already register ed to another LEC on the same ELAN.

For example, if a LES is faulty, when a LEC disconnects from the LES, the LES might fail to register the chan ge. When the LEC tries to rejoin the LES, the LES still has that LEC’s ATM address in its database , and thinks that two devices have the same ATM address.

You may have accidentally entered the same ATM addresses twice.

Ensure that AT M addresses are unique. Check the LES database for dup li ca te addresses.

(continued)

Table 9-3

Last LEC Failure Reason

State Possible Causes Possible Solutions

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Insufficient Resources

There are insufficient resources to grant a request.

Too many connections have been requeste d and the tables used by the LES may be full, and the connection cannot be set up.

The ATM Switch is busy and cannot provide LECS functionality.

There is a mismatch between the VPI/ VCI range supported by adjacent ATM devices.

Example:

If Switch A supports VPI/VCI values 7:511 and Switch B only supports values up to 7:255, w hen Si gn all i ng tries to set up a connect ion using the VPI/VCI value 7:256, Switch B rejects the connection.

You may wish to consider extending or restructuring your network.

Use a separate ATM Switch for LECS functionality.

Make the MAX VPI/VCI Bits compatible.

Access Denied

The L ES has denied the LEC access to the ELAN for security reasons.

The LEC is t rying to j oin an ELAN that it is not allowed to access.

Check your LANE Services setup.

(continued)

Table 9-3

Last LEC Failure R eason

State Possible Cau ses Possible Solu ti o ns

Invalid Requestor ID

The

LEC Identifier

(LECID)

is not zero, or is not recognized as this LEC’s LECID.

There is a problem with the L EC so ftware.

Contact 3Com Support.

Invalid LAN Destination

You are trying to register a multicast addre ss with th e L E S.

You may have configured an illegal Local Administration Address.

Check that the Local Administrat ion Address is valid.

Local Administration Addre ss setup is beyond the scope of this guide.

Invalid ATM Address

Source or destination ATM address is not in a recognized format.

The ATM address field may have been corrupted or not in the corr ect format.

For e xamp le, it m ay be in E.164 when OSI N-SAP address coding is required.

Contact your supplier or 3Com Technical Support.

No Configuration

The LECS/LES does not recognize the LEC or the requested ELAN

The MAC address may be invalid.

The LEC may be requesting a resource that is on an ELAN whic h has a different LAN type to the LEC.

You may have entered an invalid ELAN name.

Check that each MAC address on y our network is unique.

Check the LAN type used.

Check that the ELAN name is correct, and the ELAN has been set up correctly.

Table 9-3

Last LEC Failure Reason

State Possible Causes Possible Solutions

ATM VLAN LEC Status 9-9

LEC Operation at Failure

Identifies the operation that was being carried out when the LEC setup failed. This field should be used in conjunction with the Last LEC Failure Reason to identify the cause of the problem. The possible operations are shown in Table 9-4.

LE_CONFIGURE Error

This state may be given to refuse a service without giving a specific reason.

The information provided by the LEC may be invalid.

You may have entered an invalid ELAN name.

As this state is used to indicate a range of problems , you shou ld chec k the other states and solutions described in this table. If this does not resolve the problem c ontact 3Com Technical Support.

Check that the ELAN name is correct, and the ELAN has bee n set up correctly.

Insufficient Information

The LEC has not provided sufficient information to allow the LECS to assign it to a spec ific ELAN.

The MAC address may be invalid.

The LE C may b e requesting a resource that is on an ELAN which has a different LAN type to the LEC.

You may have entered an invalid ELAN name.

Check that each MAC address on your network is unique.

Check the LAN type used.

Check that the ELAN name is correct, and the ELAN has bee n set up correctly.

Table 9-3

Last LEC Failure R eason

State Possible Cau ses Possible Solu ti o ns

Table 9-4

LEC O peration at Failure

Operation Description None

There are no known operation failures.

Calling LECS

The LEC is tryi ng to connect to the LECS to receive LANE configuration information.

Reading Configuration from LECS

The LEC receives configuration information from the LECS in preparation for joining the LES.

Joining LES

The LEC is trying to join the ELAN by registering itself with the LES that controls that ELAN.

When the LEC has joined the LES, it is given a unique

LAN Emulation Client

Identifier (LECID)

, knows the Emulated LAN’s maxim um frame size , and knows its LAN type (either Ethernet or Token Ring).

Initial Registration

After joining, a LEC can register any number of MAC addresses and/or Route Descriptors (for Token Ring implementations).

Connecting to BUS

In order to establish a connection to the

Broadcast and Unknown Server

(BUS)

the LEC requir es the broadcast address. It requests the broadcast address from the LES.

Operational

The LEC is now part of the ELAN.

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Frames Received

The number of Ethernet frames

received by the LEC.

Frames Transmitted

The number of Ethernet frames

transmitted by the LEC.

Octets Received

The number of Ethernet octets

received by the LEC.

Octets Transmitted

The number of Ethernet octets

transmitted by the LEC. If you see the following symptoms, there may be a

problem at the ATM Switch end of the connection: The LEC is

active

and the

LEC Operation at Failure

None

, but the frames or octets counters are showing

zero.

If you have followed the troubleshooting instructions in this section and within Appendix D, and you still have a problem, contact IBM Technical Support. Refer to Appendix E for details.

The following button is available on this screen:

CLEAR SCREEN COUNTERS

ATM Physical Layer Statistics

The Physical Layer Statistics screen shows

SONET STS-3c

and

SDH STM-1

error statistics. These statistics are used to track down problems with the physical connection, and are more useful in a WAN environment.

To access Phy s ical Layer statistics, first access the ATM Port Statistics screen, as described in “ATM Port Statistics” on page 9-3, and then select the PHYSICAL button.

An example of the Physical Layer Statistics screen is shown in Figure 9-5 on page 9-11, and the statistics are described in the following text.

Port

Identifies the currently selected port.

OCD State

Shows the

Out of Cell Delineation (OCD)

state. The OCD State is set to

Fail

when seven consecutive cells have had Header Error Control violations. This implies that the cell has been corrupted and that there is probably a hardware problem with the ATM Module or ATM Swit c h .

The OCD State is only set to OK when six good cells are received by the ATM Module followed by approximately 10 seconds of good signal from the ATM fiber optic cable.

ATM Physical Layer Statistics 9-11

Figure9-5

Physical Layer Statistics

Current Sample

Specifies the number of seconds

elapsed within the current sampling period. SONET/SDH counters are acc u mul ated over a perio d

of 15 minutes (900 seconds). At the end of the 15 minute sampling period, the software stores the results of the current sampling period, and resets the values shown o n the sc reen to zero.

The results of the previous 96 sampling periods can be accessed through the SONET MIB using a MIB Browser.

Physical Layer statistics are broken down into the following layers:

■

Path

— The Path Layer deals with the mapping of ATM cells to SONET or SDH frames. The ATM Module supports 1 path.

■

Line

— The Line Layer provides synchronization and multiplexing functions for the Path Layer across the physical medium.

■

Section

— The Section Layer deals with framing,

scrambling, and section error monitoring.

Physical Layer errors are measured in units called

Seconds:

each

Second

is a second in time

In the following statistics a

second

is cons id e red

errored if it contains a

Coding Violation

coding violation

occurs when the parity check in the SONET or SDH frame indicates that the cell payload has been corrupted.

second

is considered severely errored if it contains

coding violations

for a path or section, or 32

coding violations

for a line counter.

second

is unavailable if 10 continuous severely

errored

seconds

are seen at the ATM interface.

second

becomes available agai n, when 10

consecutive

seconds

are received that are not severely

errored.

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The following statistics ar e ava ilab l e:

Errored Seconds (Near)

The number of errored

seconds

at the ATM Module end of the connection.

Errored Seconds (Far)

The number of

seconds

at the

ATM Switch end of the connection.

Severe Errored Sec (Near)

The number of severely

errored

seconds

at the ATM Module end of the

connection.

Severe Errored Sec (Far)

The number of severely

errored

seconds

at the ATM Swit ch end of the

connection.

Coding Vi ol ati ons (Near)

The number of c

oding

violations

that have occurred at the A TM Module end

of the connection.

Coding Vi ol ati ons (Far)

The number of

coding

violations

that have occurred at the ATM Switch end

of the physical connection.

Unavailable Seconds (Near)

The number of

seconds

that were unavailable at the ATM interface

on the ATM Module.

Unavailable Seconds (Far)

The number of

seconds

that were unavailable at the ATM interface on the ATM Sw itch.

Using Physical Layer Statistics to Troubleshoot

This section describes how to use the physical layer statistics to track and resolve problems.

If no values are shown on the screen, the problem probably lies with the ATM Switch rather than the ATM Module. Follow the troubleshooting information in the user guide that accompanies your ATM Switch.

High values usually i ndicate that the SON ET stand ard s are incompatibl e, or th at there is a fau lt on the c ab l e. Use the following troubleshooting suggestions to try and resolve the problem:

Check that the ports at both end of the link are

enabled

Check that the cable is sec ur ely connected to th e port at both ends of the link.

Check each end of the cable to ensure that each of the fiber connectors is correctly connected. If you have connectors that can be reversed, you may need to reverse the TX and RX cable connectors at one end of the link.

Make sure that the cable does not exceed the cable length or other technical specifications. Check the cable against the technical specification given in Appendix C.

Remove any obstructions and straighten out any kinks in the cable.

If you suspect that the fiber optic connector is dirty, refer to “Cleaning Dirty Fiber Optic Connectors” on page D-24.

ATM Physical Layer Statistics 9-13

If you suspect that the fiber optic cable is not working, replace the cable with a cable known to be working, and check the Link Status LED.

Check that the cable has not been accidently plugged into an FDDI connector at one end of the connection.

Check that the ATM Module and ATM Switch are using compatible transmit clocking options.

Check that the Line Rate settings on the two devices are com patible.

If there is still a problem, contact your repair center for advice. For more details, refer to Appendix E.

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AFETY INFORMATION

You must read the following safety information before carrying out any installation or remov al of components, or any ma intenance procedures on the Switch.

Safety No tices

Safety notices are printed throughout this manual.

DANGER

notices warn you of conditions or p rocedures that can result in death or severe personal injury. CAUTION notices warn you o f conditions or procedures that can cause personal injury that is neither lethal not extremely hazardous.

World Trade Safety Information

Some countries require the safety information contained in publications to be presented in their national languages. Before using an English-language publication to set up , install, or operate this IBM product, you first should become familiar with the related safety information.

DANGER: Before you begin to install this product, read the safety information in Caution: Safety Infor- mation – Read This First, SD21-0030. This booklet describes safe procedures for cabling a nd plugging in electrical equipment.

Varning — livs fara: Innan du börj a installera den här produkten bör du läsa säkerhetsinformtionen i dokumentet Varning: Säkerhetsföreskrifter – Läs detta först, SD21-0030. Där beskrivs hur du på ett säkert sätt ansluter elektrisk utrustning.

Fare: Før du begynner å installere dette produktet, må du lese sikkerhetsinformasjonen i Advars el: Si k- kerhetsinformasjon – Les dette først, SD21-0030 som beskriver sikkerhetsrutinene for kabling og tilkobling av elektrisk utstyr.

Fare: Før du installerer dette produkt, skal du læ se sikkerhedsforskrifterne i NB: Sikkerhedsforskrifter – Læs dette først, SD21-0030. Vejiedningen beskriver den fremgangsmåde, d u skal bruge ve d tilslutning af kabier og udstyr.

Gevarr: Voordat u begint met de installatie van dit produkt, moet u eerst de veiligheidsinstructies lezen in de brochure PAS OP! Veiligheidsinstructie s – Lees dit eerst, SD21-0030. Hierin wordt beschreven hoe u electrische apparatuur op een veilige manier moet bekabelen en aansluiten.

A-2 A

PPENDIX

A: S

AFETY INFORMATION

Gevarr:

Voordat u begint met het installeren van dit produkt, dient u eerst de veiligheidsrichtlijnen te lezen die zijn vermeld in d e publikatie

Caution:

Safety Informtion – Read This First

, SD21-0030. In dit boekje vindt u veilige p rocedures voor het aansluiten van elektrische appratuur.

Vo rs icht:

Bevor mit der Installation des Produktes

begonnen wird, die Sicherheitshinweise in

Achtung:

Sicherheitsinformationen – Bitte zuerst lesen

, IBM Form SD21-0030. Diese Veröffentlichung beschreibt die Sicherheitsvorkehrungen für das Verkabeln und Anschließen elktrische r Geräte.

Danger:

Avant d'installer le présent produit, con-

sultez le livret

Attention: Informations pour la sécu-

rité – Lisez-moi d'abord,

SD21-0030, qu i décrit les procédures à respecter pour effectuer les opérations de câblage et brancher les équipements électriques en toute sécurité.

Danger:

Avant de procéder à l'installation de ce produit, lisez d'abord les consignes de sécurité dans la brochure

ATTENTION: Consignes de sécurité – A

lire au préalable

, SD21-0030. Cette brochure décrit les procédures pour câbler et co nnecter les appareils électriques en toute sécurité.

Pericolo:

prima di iniziare l'installazione di questo prodotto, l eggere le inform azioni relative alla sicurezza riportate nell'opuscolo

Attenzion: Infor-

mazioni di sicurezza – Prime informazioni da leggere

in cui sono descritte le procedure per il cablaggio ed il collegamento di apparecchiature elettriche.

Perigo:

Antes de iniciar a instalação deste produto,

leia as informações de segurança

Cuidado: Infor-

mações de Segurança – Leia Primeiro

, SD21-0030. Este documento descreve como efectuar, de um modo seguro, as ligações eléctricas dos equipamentos.

Peligro:

Antes de empezar a instalar este producto,

lea la informaci ón de segurid ad en

Ate nc ión: In fo r-

mación de Seguridad – Lea Esto Primero

, SD21-0030. Este doc umento describe lo s procedimientos de seguridad para cablear y e nchufar equipos eléctricos.

Perigo:

Antes de começ ar a instalar este prod uto,

leia as informações de segurança contidas em

Cuidado: Informações Sobre Segurança – Leia Isto Primeiro

, SD21-0030. Esse folhet o descreve procedimentos de seguranç a para a insta lação de cabos e conexões em equip amentos elétricos.

VARRA:

Ennen kuin aloitat tämän tuotteen asen-

nuks en, lu e julk aisuss a

Varoitus: Turvaohjeet – Lue

tämä ensin

, SD21-0030, olevat turvaohj eet. Tässä kirjasessa on ohjeet siitä, miten sähkölaitteet kaapeloidaan ja kytketään turvallisesti.

Safety Notices A-3

Vigyázat: Mielôtt megkezdi a berendezés üzembe helyezését, olvassa el a Caution: Safety Information – Read This First, SD21-0030 könyvecskében leírt biztonság i információk at. Ez a könyv leír ja, milyen biztonsági intézkedéseket kell megtenni az elektromos berendezés huzalozásakor illetve csatlakoztatásakor.

Pozor: Preden zaènete z i nstalacijo tega produkta prebertte poglavje: 'Opozorilo: Informacije o varnem rokovanju - preberi pred uporabo ,” SD21-0030. To poglavje opisuje pravilne postopke za kabliranje,

A-4 A

PPENDIX

A: S

AFETY INFORMATION

ATTENTION

DANGER:

Installat ion an d remo val of t he un it must

be carried out by qualified personnel only.

DANGER:

L'insta llation et l'enlè vemen t de l' unité doivent être faits seulement par le personnel qualifié.

DANGER:

Ein- und Ausbau des Gerätes ist nur von Fachpersonal vorzunehmen.

Gevaar!

De eenheid m ag alleen worden geïn-

stalleerd of verwijderd doorbevoegde person en.

Perigo:

A instalação e remoção da unidade deve ser

feita apenas porpessoal especializado.

Fare!

Installation og afmontering af enheden skal

udføres afuddannet personale.

Gevaar:

Installat ie en verwijde ring v an de e enheid moet uitsluitend worden uitgevoerd door getraind personeel.

Verra:

Yksikön saavat asentaa ja irrottaa vain tähän

koulutetut henkilöt.

Pericolo:

L’installazione e la rimozione d ell’unità devono essere eseguite esclusivamente da personale specializzato.

Fare:

Det er bare kvalifisert personale som kan

installere og ta ut enheten.

Perigo:

A instalação e a remoção da unidade devem ser efectuadas apenas por pessoal qualificado.

Peligro:

La instalación y extracción de la unidad

debe efectuarseúnicamente por personal cualificado.

Fara:

Installation och flyttning av enheten måste

utföras av utbildad personal.

Class 1

LED Product

Class 1

LED Product

LED

Klasse 1

LED

Klasse 1

Luokan 1

LEDLAITE

Luokan 1

LEDLAITE

Appareil a LED

de Classe 1

Appareil a LED

de Classe 1

Neodstraňujte desky modulů, pokud je připojeno napájení.

Safety Notices A-5

DANGER: This unit operates under SELV conditions (Safety Extra Low Voltage) according to IEC 950, the conditions of which are maintained only if the equipment to which it is connected is also operational under SELV.

DANGER: Cette unité marche sous les condition s SELV (Safety Extra Low Voltage) conformément à IEC 950, ces conditions sont m aintenues seulement si le matériel auquel elle est branchée, est aussi en exploitation sous SELV.

DANGER: Das Gerät wird mit Sicherheits-Kleinspannung nach IEC 950 (SELV = Safety Extra Low Voltage) betrieben. Angeschloßen werden können nur Geräte, die ebenfalls nach SELV b etrieben werden.

Gevarr: D eze eenheid w erkt onder SELV (Safety Extra Low Voltage) volgens IEC 950, waarvan de voorwaarden alleen beho uden blijven indien d e apparatuur waarop het is aangesloten, ook onder SELV werkt.

Perigo: Esta unidade funciona sob condições SELV (Safety Extra Low Voltage) de acordo co m IEC 950 mas, essa situação é mantida apenas se oequipamento ao qual ela est conectada também funcionar sob a condição SELV.

Fare! Denne enh ed fungerer ved svagstrøm i he nhold til betingelsern ei IEC 950. D isse betingelser overholdes kun, hvis det udstyr, enheden er sluttet til, også fungerer ved svagstrøm.

Монтаж и демонтаж оборудования должен выполнять только квалифицированный персонал.

A-6 A

PPENDIX

A: S

AFETY INFORMATION

Gervaar:

Deze eenheid werkt onder extra lage spanning (SELV, Safety Extra Low Voltage) volgens norm IEC 950. Er wo rdt uitsluitend aan dez e norm voldaan zolang de appara tuur waarmee de eenhe id is verbonden, ook werkt on der SELV.

Vaara:

Tämä yksikkö sisältää kansainvälisen turvastandardin IEC 950 mukaisia SELV (Safety Extra LowVoltage) -suojajännitepiirejä. Yksikkö täyttää standardissa kuvatut ehdot vain, jos laite, jo honyksikkö liitetään, käyttää SELV-piirejä.

Pericolo:

Questa unità funziona i n condizioni di bassissima tensionedi sicurezza (SELV, Safety Extra Low Voltage) secondo l’IEC 950.Tali condizioni so no rispettate solo se anche l’apparecchiaturaa cui l’unità è collegata funziona in SELV.

Fare:

Dette utstyret drives med strøm fra kretser med ekstra lav spenning (SELV-kretser) i henhold til standarden IEC 950. Denne s penningen opprettholdes kun dersom utsty ret som det er koblet til, også drives av såkalte SELV-kretser.

Perigo:

Esta unidade funciona sob condições SELV (Safety Extra LowVoltage - Tensão Muito Baixa, de Segurança), de acordo com anorma IEC 950. O estabelecido nesta norma só pode rá se r m antidos e o equipamento ao qual a unidade for ligada também funcionarsob aquelas condições SELV.

Peligro:

Esta unidad opera bajo condiciones SELV (Safety Extra Low Voltage /Voltaje Extra Bajo de Seguridad) de acuerdo a la norma IEC 950, sibien tales condiciones únicam ente se mantienen s i el equipo alque se conec tan es asimismo opera cional bajo SELV.

Fara:

Den här enheten arbetar under villkoren för kyddsklenspänning (Safety Extra Low Voltage) enligt IEC 950. Dessa villkor uppfylls endast om utrustning till vilken enheten ansluts också arbetar med skyddsklenspänning.

Safety Notices A-7

Это устройство работает по стандарту IEC 950 в условиях Безопасно низкого напряжения (SELV) только при условии, что все оборудование в цепи отвечает стандартам SELV.

A-8 A

PPENDIX

A: S

AFETY INFORMATION

CREEN

CCESS

IGHTS

This appendix lists the security access level you must have to be able to access the ATM Module local management screens, and lists the type of action that can be performed for each security level.

This appendix only covers screens specifically associated with ATM functionality. Refer to the user guide which accompanies your IBM 8271 Nways Ethernet LAN Switch for additional screen access rights.

The general actions that can be performed by users for each of the security access levels is as follows:

Security/Specialist — read and write Manager — read and write Monitor/Secure Monitor — read only

Table B- 1 s hows the access rights required for each of the A TM screens.

Table B-1

Access Rights

Screen Available to access level... ATM Mod ul e

Configur ati o n

Manager Security

ATM LEC Setup

Security Manager

ATM ARP Table

Manager Monitor Secu rit y

ATM Port Setup

Manager Monitor Security

ATM Connection Table

Manager Monitor Security

ATM Physic al Layer

Manager Monitor Security

ATM Port Statistics

Manager Monitor Security

ATM VLAN LEC Status

Manager Monitor Secu rity

B-2 A

PPENDIX

B: S

CREEN ACCESS RIGHTS

ATM M

ODULE TECHNICAL SPECIFICATIONS

Environmental Specifications

The environmental specifications for the ATM Module are shown in Table C-1.

ATM Cable Specification

In addition to adhering to your local standards, all cables must conform to:

The American National Standard ATM Physical Layer Medium Dependent (PMD) standard, ISO.166-1990, American National Standards Institute.

The ATM cable you connect to the ATM Module must conform to the Multi-Mode Fiber (MMF-PMD) standard defined by ANSI x.3-166-1992.

IBM supports 62.5/125mm Multi-Mode Fiber (MMF-PMD). The maximum inter-station distance (including device-to-network connectors) should not exceed 2 kilometers (1.25 miles).

Table C-2 on page C-2 shows the cable specifications for standard multi-mode cabling.

Table C-1

Environ men tal Spec i fications Operating Temperature 0 to 50° C / 32 to 122°F Operating Humidity 10–95% relative humidity,

non-condensing

Standards EN60068 (IEC68)

Safety Agency Certifications UL 1950,

EN60950, CSA 22.2 No. 950, ECMA 97

Electromagnetic Emissions (Agency Certification)

EN55022 Class B, FCC Part 15 Class A, C108.8-M1983 Class A, EN 50082-1 (IEC801 Parts 2-5), EN60555 Part 2

C-2 A

PPENDIX

C: ATM M

ODULE TECHNICAL SPECIFICATIONS

Maximum attenuation includes attenuation and the loss induced by other components such as connectors, splices, and the mating of unlike fiber types. Although some 2km (1.25 miles) cables have a total attenuation of less than 11dB, the 2km (1.25 miles) inter-station distance m ust be m ain tai ne d to comply with modal bandwidth requirements.

The maximum attenuation value in this table is based on a cable diameter of 62.5, 80 or 100mm.

Table C-3 shows the alternative Multi-Mode fiber types that can be used.

If you are using fiber with a diameter of 50mm and have IBM 8271 Nways Ethernet LAN Switch equipment at both ends of the link, substitute 8.0dB for the maximum attenuation. If IBM 8271 Nways Ethernet LAN Switch equipment is only at one end, substitute 6.0dB for the maximum attenuation value.

If you are using equipment at the end of the link from a vendor other than IBM, you must perform a separate loss budget analysis. Contact the vendor(s) for values to use in your analysis.

Does the Cable Provide Sufficient Bandwidth?

Bandwidth for multi-mode fiber is referred to as modal bandwidth because it varies with the modal field (or core diameter) of the fiber.

Modal bandwidth is specified in units of MHz.km, which indicates the amount of bandwidth supported by the fiber for a 1km (0.625 miles) distance. Your cable must have a Modal bandwidth of 500MHz, which allows the cable to support end-to-end bandwidth of 250MHz at the maximum 2km (1.25 miles) distan c e.

Table C-2

Standard Multi-mode Cable Specifications

Specification Description

Core 62.5µm diameter Cladding 125µm diameter nominal

122µm minimum

128µm maximum Numerical aperture 0.275 Maximum attenuation 11dB (including 1dB allowed for

reflection and dispersion penalties) Modal bandwidth 500 MHz.km Maximum distance between

nodes

2km (1.25 miles)

Output power (from transceiver) -20dB minimum

-14dB maximum

Receiver power -31dB minimum sensitivity

-14dB maximum sensi t ivity

Table C-3

Alternative Multi-mode Cable Specifications

Core (Pm) Cladding (Pm) Numerical Aperture

50 125 0.20 50 125 0.22 85 125 0.28 100 140 0.29

ATM Cabl e Spec ifica tio n C-3

To check that the bandwidth of your fiber is within an acceptable range:

Divide the amount of bandwidth available according to the fiber specification by the total length of fiber (km).

If the result is lower th an 25 0M H z, the link may be prone to bit errors. You should shorten the length of the fiber or use a different fiber until the result of the calculation reaches 250MHz.

Example:

A cable with modal bandwidth of 500 MHz.km will have 250 MHz of bandwidth at 2km (1.25 miles).

The same cable would have a 500MHz of bandwidth at 1km (0.625 miles).

A fiber cable with a bandwidth specification of 200 MHz.km would have only 100MHz of bandwidth at 2km (1.25 miles), which would not support ATM. In this case, another type of fiber which has a bandwidth of 155MHz would be required.

C-4 A

PPENDIX

C: ATM M

ODULE TECHNICAL SPECIFICATIONS

ROUBLESHOOTING

How to Use this Guide to Troubleshoot

This troubleshooting section describes how to identify the cause of a problem and suggests possible solutions. Troubleshooting has been divided into four sections.

■

Using LEDs

LEDs on the Switch and ATM Module provide valuable status information that can be used for troubleshooting. You may find it useful to familiarize yourself with these LEDs before reading the troubleshooting suggestions in the following sections.

■

Identify the Problem

Use this section when you do not know the cause of the problem.

■

Solving a known Problem

Use this section when you have detected a problem, and want to look up possible solutions. You should read this troubleshooting information in conjunction with the troubleshooting provided in the user guide that accompanies your Switch.

■

Cleaning D irt y Fiber Optic Conn ecto rs

This section tells you how to clean the fiber optic connectors on the ATM Module and connecting cables.

If you have problems that are not addressed by troubleshooting information in this guide, contact IBM Technical Support, or your service person. For Technical Support information refer to Appendix E.

D-2 A

PPENDIX

D: T

ROUBLESHOOTING

Using LEDs

Table D-1 describes the LEDs on the Switch, and Table D-2 describes the LEDs on the ATM Module.

Table D-1

LEDs on the Switch

LED Name Color/State Indicates MGMT

(On the front of the Switch)

Green

Green flashing

Yellow

Yellow flashing

OFF

Switch and ATM Module are operating normally.

Switch or ATM Module is either downloading software or initializing, (which includes a

Power On Self Test

Switch has failed its

Power On Self

Test (POST

)

ATM Module failed its

Power On Self

Test (POST)

No power to the Switch.

Module

(On the front of the Switch)

Green Green

flashing Green

(long on, short off)

Yellow

Yellow flashing

OFF

ATM port enabled; link present. ATM port disabled; link present.

This LED will flash until all configured LECs have successfully joined their ELANs.

ATM agent softwar e is not installed correctly, or the ATM Module has failed its POST (if the MGMT LED is flashing yellow).

Switch has not recogni ze d the ATM Module.

The ATM Module is not ins tall e d, or a link is not present on the ATM port, or the ATM Switch is not on.

Table D-2

LEDs on the ATM Module

LED Name Color/State Indicates Far End Status

(On ATM Module)

Green

OFF (and Link Status LED is Green)

OFF (and Link Status LED is OFF)

The ATM Switch has not detected an error on the ATM Module’s

transmit

link.

The AT M Switch at the far end of the connection has detected a problem with th e A TM Module ’s

transmit

connecti on, and notified the ATM Modu le. For example, the

transmit

half o f t he ATM Module’s cable has been disconnected at either the ATM Module end or ATM Switch end of the c onn ection.

The cable between the ATM Module and ATM Switch has been disconne cte d.

Link Status

(On ATM Module)

Green

OFF

A link i s prese nt on th e ATM port, and the port is receiving valid SONET frames.

The Link is not present on the ATM Port.

(On ATM Module)

Yellow

OFF

The ATM port is transmitting Ethernet, LANE, Signalling or control frames.

The A TM port is not transmitt ing cells.

(On ATM Module)

Yellow

OFF

The A TM p ort is r ec eivin g d ata cells.

The ATM port is not receiving incoming cells.

Identifying the Problem D-3

Identifying the Problem

This section describes how to identify problems, and suggests possible solutions. Flow diagrams have been used to summarize the process, and each step shown in the flow diagrams is described in more detail in the text.

This section assumes that the following conditions have been met:

■

The A TM Modul e has been inst al led correctly, as described in Chapter 6, “Installing and Setting Up the Module”.

■

The device is “alive” when pinged, and can be accessed through the local management screens.

■

Both the ATM Module and the ATM Switch or attached ATM device are using the same physical standard; eith er

SONET STS-3c

SDH STM-1

D-4 A

PPENDIX

D: T

ROUBLESHOOTING

Figure D-1

Troubleshooting Flow Diagram

Identifying the Problem D-5

The numbered st ep s in th is se ct ion relate to the numbered steps shown in Figure D-1.

Access the Physical Layer Statistics Screen

Select the SWITCH MANAGEMENT option from the Main Menu. The S witc h Management s cr een i s displayed.

Ensure that the Port option is selected in the Management Level field.

Ensure that the ATM port number is entered in the Port ID field. For example the ATM port is:

■

Port 13 on an IBM 8271 Nways Ethernet LAN Switch Model 612 and IBM 8271 Nways Ethernet LAN Switch Model 712

■

Port 25 on an IBM 8271 Nways Ethernet LAN Switch Model 624 and IBM 8271 Nways Ethernet LAN Switch Model 524

Select the STATS button. The AT M Port Statistics screen is displa ye d.

Select the PHYSICAL button to display the SONET or SDH physical layer statistics. An example of the Physical Layer Statistics screen is shown in Figure D-2.

Figure D-2

ATM Phys ical Layer Statistics

Are there Physical Layer Errors?

If the OCD State field is set to

Fail

, there is a

problem with the physical connection.

If there are a lot of errors, there is a problem with the physical connection.

Is the error rate high?

Yes

— go to step 3.

— go to step 4.

D-6 A

PPENDIX

D: T

ROUBLESHOOTING

Check the Physical Connections

Check that the Link Status and Far End Status LEDs on the ATM Module are ON and lit green. If one or both of the LEDs is not lit, there is a problem with the physical connection. Follow the troubleshooting information below:

Ensure that both devices are powered-up, and that the ports at both ends of the link are enabled.

Ensure that the cable is securely connected to the port at both ends of the link.

Check each end of the cable to ensure that each of the fiber connectors is correctly connected. If your connectors can be reversed, you may need to reverse the TX and RX cable connectors at one end of the link.

Remove any objects obstructing the cable and straighten out any kinks in the cable.

If you suspect that the fiber optic connector is dirty, see “Cleaning Dirty Fiber Optic Connectors” in this sectio n.

Check that your cable meets the specifications described in “ATM Cable Specification” on page C-1

Replace the cable with a cable known to be working, and check the Link Status LED again.

If there is still a problem, contact your repair center for advice. For more details, see Appendix E.

Access the ATM Port Setup Screen

Select the SWITCH MANAGEMENT option from the Main Menu. The Switch Management screen is displayed.

Ensure that the

Port

option is sele cted in the

Management Level

fiel d .

Ensure that the ATM port number is entered in the

Port ID

field. For example the ATM port is:

■

Port 13 on an IBM 8271 Nways Ethernet LAN Switch Model 612 and IBM 8271 Nways Ethernet LAN Switch Model 712

■

Port 25 on an IBM 8271 Nways Ethernet LAN Switch Model 624 and IBM 8271 Nways Ethernet LAN Switch Model 524

Select the SETUP button to display ATM port setup information. An example of the The A TM Por t Setup screen is shown in Figure D-3.

Figure D-3

ATM Port Setup Screen

IBM OPTIONS ATM OC-3c User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual