Hitron-Technologies CGN2-ROG, CVW-30360 User Manual

USER’S GUIDE

CGN2 RESIDENTIAL CABLE MODEM

VERSION 2.0 - FEBRUARY 2012

HITRON CGN2 USER’S GUIDE

ABOUT THIS USER’S GUIDE

INTENDED AUDIENCE

This manual is intended for people who want to configure the CGN2’s features via its Graphical User Interface (GUI).

HOW TO USE THIS USER’S GUIDE

This manual contains information on each the CGN2’s GUI screens, and describes how to use its various features.



Use the Introduction (page 12) to see an overview of the topics covered in this

manual.



Use the Table of Contents (page 7), List of Figures (page 10) and List of Tables

(page 11) to quickly find information about a particular GUI screen or topic.



Use the Index (page 110) to find information on a specific keyword.



Use the rest of this User’s Guide to see in-depth descriptions of the CGN2’s

features.

COMPLIANCES

FCC INTERFERENCE STATEMENT

This equipment has been tested and found to comply with the limits for a Class B digital device pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against radio interference in a commercial environment.

This equipment can generate, use and radiate radio frequency energy and, if not installed and used in accordance with the instructions in this manual, may cause harmful interference to radio communications.

Operation of this equipment in a residential area is likely to cause interference, in which case the user, at his own expense, will be required to take whatever measures are necessary to correct the interference. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one of the following measures:



Reorient or relocate the receiving antenna.



Increase the separation between the equipment and receiver.



Connect the equipment into an outlet on a circuit different from that to which the

receiver is connected.



Consult the dealer or an experienced radio/TV technician for help.

The device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate this equipment.

IEEE 802.11b or 802.11g operation of this product in the U.S.A is firmware-limited to channels 1 through 11.

IMPORTANT NOTE:

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FCC Radiation Exposure Statement:

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator & your body.

This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter.

The availability of some specific channels and/or operational frequency bands are country dependent and are firmware programmed at the factory to match the intended destination. The firmware setting is not accessible by the end user.

Note to CATV System Installer - The cable distribution system should be grounded (earthed) in accordance with ANSI/NFPA 70, the National Electrical Code (NEC), in particular Section 820.93, Grounding of Outer Conductive Shield of a Coaxial Cable. 107 SMCD3G3-CCR 4-Port Gateway Administrator Manual

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About This User’s Guide ................................................................ 2

Compliances .................................................................................... 5

Table of Contents ............................................................................ 7

List of Figures ............................................................................... 10

List of Tables ................................................................................. 11

Introduction ................................................................................... 12

1.1 CGN2 Overview ................................................................................ 12

1.1.1 Key Features ............................................................................ 13

1.2 Hardware Connections ...................................................................... 14

1.3 LEDs ................................................................................................. 18

1.4 IP Address Setup .............................................................................. 21

1.4.1 Manual IP Address Setup ......................................................... 22

1.5 Logging into the CGN2 ...................................................................... 23

1.6 GUI Overview .................................................................................... 24

1.7 Resetting the CGN2 .......................................................................... 25

Status ............................................................................................. 26

2.1 Cable Overview ................................................................................. 26

2.1.1 DOCSIS .................................................................................... 26

2.1.2 IP Addresses and Subnets ....................................................... 27

2.1.2.1 IP Address Format ........................................................... 27

2.1.2.2 IP Address Assignment .................................................... 27

2.1.2.3 Subnets ............................................................................ 28

2.1.3 DHCP ........................................................................................ 29

2.1.4 DHCP Lease ............................................................................. 30

2.1.5 MAC Addresses ........................................................................ 30

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2.1.6 Routing Mode ........................................................................... 31

2.1.7 Configuration Files .................................................................... 31

2.1.8 Downstream and Upstream Transmissions .............................. 31

2.1.9 Cable Frequencies .................................................................... 31

2.1.10 Modulation .............................................................................. 32

2.1.11 TDMA, FDMA and SCDMA .................................................... 32

2.2 The System Info Screen .................................................................... 33

2.3 The Initialization Screen .................................................................... 37

2.4 The CM Status Screen ...................................................................... 38

2.5 The Password Screen ....................................................................... 41

2.6 The Capability Screen ....................................................................... 42

WAN/LAN ....................................................................................... 45

3.1 WAN/LAN Overview .......................................................................... 45

3.1.1 WAN and LAN .......................................................................... 45

3.1.2 LAN IP Addresses and Subnets ............................................... 46

3.1.3 DNS and Domain Suffix ............................................................ 46

3.1.4 Debugging (Ping and Traceroute) ............................................ 46

3.2 The IP Screen ................................................................................... 47

3.3 The Shared Media Screen ................................................................ 50

3.4 The Debug Screen ............................................................................ 51

3.5 The Backup Screen ........................................................................... 52

Firewall ........................................................................................... 54

4.1 Firewall Overview .............................................................................. 54

4.1.1 Firewall ..................................................................................... 54

4.1.2 Intrusion detection system ........................................................ 55

4.1.3 Ping ........................................................................................... 55

4.1.4 MAC Filtering ............................................................................ 55

4.1.5 IP Filtering ................................................................................. 55

4.1.6 Port Forwarding ........................................................................ 56

4.1.7 Port Triggering .......................................................................... 56

4.1.8 DMZ .......................................................................................... 56

4.2 The Firewall Options Screen ............................................................. 56

4.3 The Filter Setting Screen .................................................................. 57

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4.3.1 Adding or Editing an IP Filtering Rule ....................................... 63

4.4 The Forwarding Screen ..................................................................... 65

4.4.1 Adding or Editing a Port Forwarding Rule ................................ 67

4.5 The Port Triggering Screen ............................................................... 69

4.5.1 Adding or Editing a Port Triggering Rule .................................. 71

4.6 The DMZ Screen ............................................................................... 72

Parental Control ............................................................................ 74

5.1 Parental Control Overview ................................................................ 74

5.1.1 Website Blocking ...................................................................... 74

5.2 The Website Blocking Screen ........................................................... 75

5.3 The Scheduling Screen ..................................................................... 77

5.4 The Email / Syslog Alert Screen ....................................................... 79

Wireless ......................................................................................... 83

6.1 Wireless Overview ............................................................................ 83

6.1.1 Wireless Networking Basics ..................................................... 83

6.1.2 Architecture ............................................................................... 83

6.1.3 Wireless Standards ................................................................... 84

6.1.4 Service Sets and SSIDs ........................................................... 84

6.1.5 Wireless Security ...................................................................... 85

6.1.5.1 WPS ................................................................................. 85

6.1.6 WMM ........................................................................................ 86

6.2 The Setup Screen ............................................................................. 86

6.3 The Access Control Screen .............................................................. 93

6.4 The Advanced Screen ....................................................................... 95

6.4.1 Configuring WMM Parameters ............................................... 103

Troubleshooting .......................................................................... 107

Index ............................................................................................. 110

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LIST OF FIGURES

Figure 1: Application Overview ...........................................................................13

Figure 2: Hardware Connections ........................................................................15

Figure 3: Power Adaptor .....................................................................................18

Figure 4: LEDs ....................................................................................................19

Figure 5: Login ....................................................................................................23

Figure 6: GUI Overview ......................................................................................24

Figure 7: The Status > System Info Screen ........................................................34

Figure 8: The Status > Initialization Screen ........................................................37

Figure 9: The Status > CM Status Screen ..........................................................39

Figure 10: The Status > Password Screen .........................................................42

Figure 11: The Status > Capability Screen .........................................................43

Figure 12: The WAN/LAN > IP Screen ...............................................................48

Figure 13: The WAN/LAN > Shared Media Screen ............................................51

Figure 14: The WAN/LAN > Debug Screen ........................................................52

Figure 15: The WAN/LAN > Backup Screen .......................................................53

Figure 16: The Firewall > Firewall Options Screen .............................................57

Figure 17: The Firewall > Filter Setting Screen ..................................................59

Figure 18: The Firewall > Filter Settings > Add/Edit Screen ...............................63

Figure 19: The Firewall > Forwarding Screen .....................................................65

Figure 20: The Firewall > Forwarding > Add/Edit Screen ...................................67

Figure 21: The Firewall > Port Triggering Screen ...............................................69

Figure 22: The Firewall > Port Triggering > Add/Edit Screen .............................71

Figure 23: The Firewall > DMZ Screen ...............................................................73

Figure 24: The Parental Control > Web Site Blocking Screen ............................75

Figure 25: The Parental Control > Scheduling Screen .......................................78

Figure 26: The Parental Control > Email / Syslog Alert Screen ..........................79

Figure 27: Add Target Email Address .................................................................81

Figure 28: The Wireless > Setup Screen ............................................................87

Figure 29: WPS PIN ............................................................................................89

Figure 30: The Wireless > Access Control Screen .............................................93

Figure 31: The Wireless > Advanced Screen .....................................................96

Figure 32: The Wireless > Advanced > WMM Configuration Screen ...............103

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LIST OF TABLES

Table 1: Default Credentials ................................................................................4

Table 2: Hardware Connections ........................................................................16

Table 3: LEDs ....................................................................................................19

Table 4: GUI Overview .......................................................................................24

Table 5: Private IP Address Ranges ..................................................................28

Table 6: IP Address: Decimal and Binary ..........................................................28

Table 7: Subnet Mask: Decimal and Binary .......................................................29

Table 8: The Status > System Info Screen ........................................................35

Table 9: The Status > CM Status Screen ..........................................................39

Table 10: The Status > Password Screen .........................................................42

Table 11: The Status > Capability Screen .........................................................43

Table 12: The WAN/LAN > IP Screen ...............................................................48

Table 13: The WAN/LAN > Shared Media Screen ............................................51

Table 14: The WAN/LAN > Debug Screen ........................................................52

Table 15: The LAN > Backup Screen ................................................................53

Table 16: The Firewall > Firewall Options Screen .............................................57

Table 17: The Firewall > Filter Setting Screen ...................................................60

Table 18: The Firewall > Filter Settings > Add/Edit Screen ...............................64

Table 19: The Firewall > Forwarding Screen .....................................................65

Table 20: The Firewall > Forwarding > Add/Edit Screen ...................................68

Table 21: The Firewall > Port Triggering Screen ...............................................69

Table 22: The Firewall > Port Triggering > Add/Edit Screen .............................71

Table 23: The Firewall > DMZ Screen ...............................................................73

Table 24: The Parental Control > Web Site Blocking Screen ............................76

Table 25: The Parental Control > Scheduling Screen .......................................78

Table 26: The Parental Control > Email / Syslog Alert Screen ..........................80

Table 27: The Wireless > Setup Screen ............................................................87

Table 28: The Wireless > Access Control Screen .............................................94

Table 29: The Wireless > Advanced Screen .....................................................97

Table 30: The Wireless > Advanced > WMM Configuration Screen ................103

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INTRODUCTION

This chapter introduces the CGN2 and its GUI (Graphical User Interface). It contains the following sections:



CGN2 Overview on page 12



Hardware Connections on page 14



LEDs on page 18



IP Address Setup on page 21



Logging into the CGN2 on page 23



GUI Overview on page 24



Resetting the CGN2 on page 25

1.1 CGN2 OVERVIEW

Your CGN2 is a NAT-capable cable modem and wireless access point that allows you to connect your computers, wireless devices, and other network devices to one another, and to the Internet via the cable connection.

Computers with a wired connection to the CGN2 are on the Local Area Network (LAN), computers with a wireless connection to the CGN2 are on the Wireless Local Area Network (WLAN) and the CGN2 connects to the service provider over the Wide Area Network (WAN).

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Figure 1: Application Overview

1.1.1 KEY FEATURES

The CGN2 provides:



Internet connection to cable modem service via CABLE port (F-type RF

connector)



Local Area Network connection via four 10/100/1000 Mbps (megabits per

second) Ethernet ports



Dynamic Host Configuration Protocol (DHCP) for devices on the LAN



LAN troubleshooting tools (Ping and Traceroute)



IEEE 802.11b/g/n wireless MIMO (Multiple-In, Multiple-Out) networking, allowing

speeds of up to 300Mbps



Wireless security: WEP, WPA-PSK and WPA2-PSK encryption, Wifi Protected

Setup (WPS) push-button and PIN configuration, MAC filtering,



Wired security: stateful inspection firewall with intrusion detection system, IP and

MAC filtering, port forwarding and port triggering, De-Militarized Zone (DMZ) and event logging



Parental control: scheduled website blocking and access logs

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

Settings backup and restore



Secure configuration interface, accessible by Web browser

1.2 HARDWARE CONNECTIONS

This section describes the CGN2’s physical ports and buttons.

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Figure 2: Hardware Connections

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Table 2: Hardware Connections

ON/OFF Use this button to turn your CGN2 on or off.



To turn the CGN2 on, press and hold the ON/OFF button for less than 1 second.



To turn the CGN2 off, press and hold the ON/OFF button for longer than 4 seconds.

WPS PBC Press this button to begin the WiFi Protected Setup

(WPS) Push-Button Configuration (PBC) procedure.

Press the PBC button on your wireless clients in the coverage area within two minutes to enable them to join the wireless network.

See WPS on page 85 for more information.

Reset Use this button to reboot or reset your CGN2.



Press the button and hold it for less than five seconds

to reboot the CGN2. The CGN2 restarts, using your existing settings.



Press the button and hold it for more than five seconds to delete all user-configured settings and restart the CGN2 using its factory default settings. See Resetting the CGN2 on page 25 for more information on resetting the CGN2.

NOTE: Unless you previously backed-up the CGN2’s

configuration settings prior to resetting the CGN2, the settings cannot be recovered.

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Table 2: Hardware Connections

USB The CGN2 provides one USB 2.0 host port, allowing you

to plug in a USB flash disk for mounting and sharing through the LAN interfaces via the Samba protocol (network neighborhood).

The CGN2 supports the following Windows file systems:



FAT16



FAT32



NTFS

USB devices must not drain more than 500mA

from the USB port. USB devices requiring more than 500mA should be provided with their own power source(s).

LAN1 Use these ports to connect your computers and other

LAN2

LAN3

LAN4

network devices, using Category 5 or 6 Ethernet cables with RJ45 connectors.

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Table 2: Hardware Connections

CABLE Use this to connect to the Internet via an F-type RF

cable.

POWER Use this to connect to the 12v/2A power adapter that

came with your CGN2.

NEVER use another power adapter with your

CGN2. Doing so could harm your CGN2.

Figure 3: Power Adaptor

1.3 LEDS

This section describes the CGN2’s LEDs (lights).

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Figure 4: LEDs

Table 3: LEDs

LED STATUS DESCRIPTION

WIRELESS Off The wireless network is not enabled.

Green, steady The wireless network is enabled, and no data is

being transmitted or received over the wireless network.

Green, blinking The wireless network is enabled, and data is being

transmitted or received over the wireless network.

Bi-color Wi-Fi Protected Setup (WPS) is in operation.

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Table 3: LEDs

LAN 1~4 Off No device is connected to the relevant LAN port.

Green, blinking A device is connected to the relevant LAN port via a

Fast Ethernet (100Mbps) link, and is transmitting or receiving data.

Green, steady A device is connected to the relevant LAN port via a

Fast Ethernet (100Mbps) link, but is not transmitting or receiving data.

Blue, blinking A device is connected to the relevant LAN port via a

Gigabit Ethernet (1000Mbps) link, and is transmitting or receiving data.

Blue, steady A device is connected to the relevant LAN port via a

Gigabit Ethernet (1000Mbps) link, but is not transmitting or receiving data.

Status Blinking The CGN2’s cable modem is registering with the

service provider’s CMTS.

On The CGN2’s cable modem has successfully

registered with the service provider and is ready for data transfer.

US Green, blinking The CGN2 is searching for an upstream frequency

on the CABLE connection.

Green, steady The CGN2 has successfully located and locked

onto an upstream frequency on the CABLE connection.

Blue The CGN2 is engaged in channel bonding on the

upstream connection.

Off There is no upstream activity on the CABLE

connection.

DS Green, blinking The CGN2 is searching for a downstream

frequency on the CABLE connection.

Green, steady The CGN2 has successfully located and locked

onto a downstream frequency on the CABLE connection.

Blue The CGN2 is engaged in channel bonding on the

downstream connection.

Off There is no downstream activity on the CABLE

connection.

Power On The CGN2 is receiving power.

Off The CGN2 is not receiving power.

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When you turn on the CGN2, the LEDs light up in the following order:



Power



Status



The ETH 1~4 LEDs light up as soon as there is activity on the relevant port, and

the WIRELESS LED lights up once the wireless network is ready.

1.4 IP ADDRESS SETUP

Before you log into the CGN2’s GUI, your computer’s IP address must be in the same subnet as the CGN2. This allows your computer to communicate with the CGN2.

NOTE: See IP Addresses and Subnets on page 27 for background information.

The CGN2 has a built-in DHCP server that, when active, assigns IP addresses to computers on the LAN. When the DHCP server is active, you can get an IP address automatically. The DHCP server is active by default.

If your computer is configured to get an IP address automatically, or if you are not sure, try to log in to the CGN2 (see Logging into the CGN2 on page 23).



If the login screen displays, your computer is already configured correctly.



If the login screen does not display, either the CGN2’s DHCP server is not active

or your computer is not configured correctly. Follow the procedure in Manual IP

Address Setup on page 22 and set your computer to get an IP address

automatically. Try to log in again. If you cannot log in, follow the manual IP address setup procedure again, and set a specific IP address as shown. Try to log in again.

NOTE: If you still cannot see the login screen, your CGN2’s IP settings may have

been changed from their defaults. If you do not know the CGN2’s new address, you should return it to its factory defaults. See Resetting the CGN2 on page 25. Bear in mind that ALL user-configured settings are lost.

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1.4.1 MANUAL IP ADDRESS SETUP

By default, your CGN2’s local IP address is 192.168.0.1. If your CGN2 is using the default IP address, you should set your computer’s IP address to be between

192.168.0.2 and 192.168.0.254.

NOTE: If your CGN2 DHCP server is active, set your computer to get an IP address

automatically in step 5. The CGN2 assigns an IP address to your computer. The DHCP server is active by default.

Take the following steps to manually set up your computer’s IP address to connect to the CGN2:

NOTE: This example uses Windows XP; the procedure for your operating system

may be different.

1 Click Start, then click Control Panel.

2 In the window that displays, double-click Network Connections.

3 Right-click your network connection (usually Local Area Connection) and click

Properties.

4 In the General tab’s This connection uses the following items list, scroll

down and select Internet Protocol (TCP/IP). Click Properties.

5 You can get an IP address automatically, or specify one manually:



If your CGN2’s DHCP server is active, select Get an IP address automatically.



If your CGN2’s DHCP server is active, select Use the following IP address. In the IP address field, enter a value between 192.168.0.2 and

192.168.0.254 (default). In the Subnet mask field, enter 255.255.255.0 (default).

NOTE: If your CGN2 is not using the default IP address, enter an IP address and

subnet mask that places your computer in the same subnet as the CGN2.

6 Click OK. The Internet Protocol (TCP/IP) window closes. In the Local Area

Connection Properties window, click OK.

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Your computer now obtains an IP address from the CGN2, or uses the IP address that you specified, and can communicate with the CGN2.

1.5 LOGGING INTO THE CGN2

Take the following steps to log into the CGN2’s GUI.

NOTE: You can log into the CGN2’s GUI via the wireless interface. However, it is

strongly recommended that you configure the CGN2 via a wired connection on the LAN.

1 Open a browser window.

2 Enter the CGN2’s IP address (default 192.168.0.1) in the URL bar. The Login

screen displays.

Figure 5: Login

3 Enter the Username and Password. The default login username is cusadmin,

and the default password is password.

NOTE: The Username and Password are case-sensitive; “password” is not the same

as “Password”.

4 Click Login. The System Info screen displays (see The System Info Screen on

page 33).

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1.6 GUI OVERVIEW

This section describes the CGN2’s GUI.

Figure 6: GUI Overview

Table 4: GUI Overview

Primary Navigation Bar

Secondary Navigation Bar

Main Window Use this section to read information about your CGN2’s

Each item in the Primary Navigation Bar has its own chapter in this User's Guide; items in the Secondary Navigation Bar have their own section within a chapter.

Use this section to move from one part of the GUI to another.

Use this section to move from one related screen to another.

configuration, and make configuration changes.

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1.7 RESETTING THE CGN2

When you reset the CGN2 to its factory defaults, all user-configured settings are lost, and the CGN2 is returned to its initial configuration state.

There are two ways to reset the CGN2:



Press the RESET button on the CGN2, and hold it in for ten seconds or longer.



Click WAN/LAN > Backup. In the screen that displays, click the Factory Reset

button.

The CGN2 turns off and on again, using its factory default settings.

NOTE: Depending on your CGN2’s previous configuration, you may need to re-

configure your computer’s IP settings; see IP Address Setup on page 21.

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STATUS

This chapter describes the screens that display when you click Status in the toolbar. It contains the following sections:



Cable Overview on page 26



The System Info Screen on page 33



The Initialization Screen on page 37



The CM Status Screen on page 38



The Password Screen on page 41



The Capability Screen on page 42

2.1 CABLE OVERVIEW

This section describes some of the concepts related to the Cable screens.

2.1.1 DOCSIS

The Data Over Cable Service Interface Specification (DOCSIS) is a telecommunications standard that defines the provision of data services) Internet access) over a traditional cable TV (CATV) network.

Your CGN2 supports DOCSIS version 3.0.

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2.1.2 IP ADDRESSES AND SUBNETS

Every computer on the Internet must have a unique Internet Protocol (IP) address. The IP address works much like a street address, in that it identifies a specific location to which information is transmitted. No two computers on a network can have the same IP address.

2.1.2.1 IP ADDRESS FORMAT

IP addresses consist of four octets (8-bit numerical values) and are usually represented in decimal notation, for example 192.168.1.1. In decimal notation, this means that each octet has a minimum value of 0 and a maximum value of 255.

An IP address carries two basic pieces of information: the “network number” (the address of the network as a whole, analogous to a street name) and the “host ID” (analogous to a house number) which identifies the specific computer (or other network device).

2.1.2.2 IP ADDRESS ASSIGNMENT

IP addresses can come from three places:



The Internet Assigned Numbers Agency (IANA)



Your Internet Service Provider



You (or your network devices)

IANA is responsible for IP address allocation on a global scale, and your ISP assigns IP addresses to its customers. You should never attempt to define your own IP addresses on a public network, but you are free to do so on a private network.

In the case of the CGN2:



The public network (Wide Area Network or WAN) is the link between the cable

connector and your Internet Service Provider. Your CGN2’s IP address on this network is assigned by your service provider.

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

The private network (in routing mode - see Routing Mode on page 31) is your

Local Area Network (LAN) and Wireless Local Area Network (WLAN), if enabled. You are free to assign IP addresses to computers on the LAN and WLAN manually, or to allow the CGN2 to assign them automatically via DHCP (Dynamic Host Configuration Protocol). IANA has reserved the following blocks of IP addresses to be used for private networks only:

Table 5: Private IP Address Ranges

FROM... ...TO

10.0.0.0 10.255.255.255

172.16.0.0 172.31.255.255

192.168.0.0 192.168.255.255

If you assign addresses manually, they must be within the CGN2’s LAN subnet.

2.1.2.3 SUBNETS

A subnet (short for sub-network) is, as the name suggests, a separate section of a network, distinct from the main network of which it is a part. A subnet may contain all of the computers at one corporate local office, for example, while the main network includes several offices.

In order to define the extent of a subnet, and to differentiate it from the main network, a subnet mask is used. This “masks” the part of the IP address that refers to the main network, leaving the part of the IP address that refers to the sub-network.

Each subnet mask has 32 bits (binary digits), as does each IP address:



A binary value of 1 in the subnet mask indicates that the corresponding bit in the

IP address is part of the main network.



A binary value of 0 in the subnet mask indicates that the corresponding bit in the

IP address is part of the sub-network.

For example, the following table shows the IP address of a computer (192.168.1.1) expressed in decimal and binary (each cell in the table indicates one octet):

Table 6: IP Address: Decimal and Binary

192 168 0 1

11000000 10101000 00000000 00000001

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The following table shows a subnet mask that “masks” the first twenty-four bits of the IP address, in both its decimal and binary notation.

Table 7: Subnet Mask: Decimal and Binary

255 255 255 0

11111111 11111111 11111111 00000000

This shows that in this subnet, the first three octets (192.168.1, in the example IP address) define the main network, and the final octet (1, in the example IP address) defines the computer’s address on the subnet.

The decimal and binary notations give us the two common ways to write a subnet mask:



Decimal: the subnet mask is written in the same fashion as the IP address:

255.255.255.0, for example.



Binary: the subnet mask is indicated after the IP address (preceded by a forward

slash), specifying the number of binary digits that it masks. The subnet mask

255.255.255.0 masks the first twenty-four bits of the IP address, so it would be written as follows: 192.168.1.1/24.

2.1.3 DHCP

The Dynamic Host Configuration Protocol, or DHCP, defines the process by which IP addresses can be assigned to computers and other networking devices automatically, from another device on the network. This device is known as a DHCP server, and provides addresses to all the DHCP client devices.

In order to receive an IP address via DHCP, a computer must first request one from the DHCP server (this is a broadcast request, meaning that it is sent out to the whole network, rather than just one IP address). The DHCP server hears the requests, and responds by assigning an IP address to the computer that requested it.

If a computer is not configured to request an IP address via DHCP, you must configure an IP address manually if you want to access other computers and devices on the network. See

By default, the CGN2 is a DHCP client on the WAN (the CATV connection). It broadcasts an IP address over the cable network, and receives one from the service provider. By default, the CGN2 is a DHCP server on the LAN; it provides IP addresses to computers on the LAN which request them.

IP Address Setup on page 21 for more information.

HITRON CGN2 USER’S GUIDE

2.1.4 DHCP LEASE

“DHCP lease” refers to the length of time for which a DHCP server allows a DHCP client to use an IP address. Usually, a DHCP client will request a DHCP lease renewal before the lease time is up, and can continue to use the IP address for an additional period. However, if the client does not request a renewal, the DHCP server stops allowing the client to use the IP address.

This is done to prevent IP addresses from being used up by computers that no longer require them, since the pool of available IP addresses is finite.

2.1.5 MAC ADDRESSES

Every network device possesses a Media Access Control (MAC) address. This is a unique alphanumeric code, given to the device at the factory, which in most cases cannot be changed (although some devices are capable of “MAC spoofing”, where they impersonate another device’s MAC address).

MAC addresses are the most reliable way of identifying network devices, since IP addresses tend to change over time (whether manually altered, or updated via DHCP).

Each MAC address displays as six groups of two hexadecimal digits separated by colons (or, occasionally, dashes) for example 00:AA:FF:1A:B5:74.

NOTE: Each group of two hexadecimal digits is known as an “octet”, since it

represents eight bits.

Bear in mind that a MAC address does not precisely represent a computer on your network (or elsewhere), it represents a network device, which may be part of a computer (or other device). For example, if a single computer has an Ethernet card (to connect to your CGN2 via one of the LAN ports) and also has a wireless card (to connect to your CGN2 over the wireless interface) the MAC addresses of the two cards will be different. In the case of the CGN2, each internal module (cable modem module, Ethernet module, wireless module, etc.) possesses its own MAC address.

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Hitron-Technologies CGN2-ROG, CVW-30360 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

ABOUT THIS USER’S GUIDE

COMPLIANCES

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

INTRODUCTION

1.1 CGN2 OVERVIEW

1.1.1 KEY FEATURES

1.2 HARDWARE CONNECTIONS

1.3 LEDS

1.4 IP ADDRESS SETUP

1.4.1 MANUAL IP ADDRESS SETUP

1.5 LOGGING INTO THE CGN2

1.6 GUI OVERVIEW

1.7 RESETTING THE CGN2

STATUS

2.1 CABLE OVERVIEW

2.1.1 DOCSIS

2.1.2 IP ADDRESSES AND SUBNETS

2.1.2.1 IP ADDRESS FORMAT

2.1.2.2 IP ADDRESS ASSIGNMENT

2.1.2.3 SUBNETS

2.1.3 DHCP

2.1.4 DHCP LEASE

2.1.5 MAC ADDRESSES