User`s guide

STATUS

HITRON CGN USER’S GUIDE

3.1.5 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 CGN via one of the LAN ports) and also has a wireless card (to

connect to your CGN over the wireless interface) the MAC addresses of the two

cards will be different. In the case of the CGN, each internal module (cable modem

module, Ethernet module, wireless module, etc.) possesses its own MAC address.

3.1.6 ROUTING MODE

When your CGN is in routing mode, it acts as a gateway for computers on the LAN to

access the Internet. The service provider assigns an IP address to the CGN on the

WAN, and all traffic for LAN computers is sent to that IP address. The CGN assigns

private IP addresses to LAN computers (when DHCP is active), and transmits the

relevant traffic to each private IP address.

NOTE: When DHCP is not active on the CGN in routing mode, each computer on the

LAN must be assigned an IP address in the CGN’s subnet manually.

When the CGN is not in routing mode, the service provider assigns an IP address to

each computer connected to the CGN directly. The CGN does not perform any

routing operations, and traffic flows between the computers and the service provider.

Routing mode is not user-configurable; it is specified by the service provider in the

CGN’s configuration file.