Router Id; Transit Area Id - Bay Networks NauticaRS Reference Manual

Router ID

Transit Area ID

117237-E Rev.00
The ID of a router is derived from its IP address. Router ID is a
hexadecimal number. For example, if a router has an IP address of
192.1.1.1, the Router ID is calculated as follows.
1. Calculate the hexadecimal value of 192 = C0
2. Calculate the value 0f 1 = 01
3. Router ID = C0010101
Note: The decimals in the IP address do not form part of the
Hex Router ID. Calculate each part of the IP Address
separately, and do not enter it as one number (an IP Address
comprises four numbers).
The Transit Area ID, is the area number through which the data
has to pass (transit) in order to reach the ABR with a link into the
backbone.
For example, in a network of four areas, Area 4 can only reach
Area 0 by passing through Area 2 using a router with an IP
address of 192.1.1.1. In this case, the following virtual link is
created:
bcc> co ip os vl c0010101/2
Where co moves the router from BCC mode (bcc>) to config
mode (box#), ip takes BCC into the IP context, os moves you to
the ospf# object, vl sets up the Virtual link, c0010101 is the router
id (198.1.1.1) and 2 is the area passed through to reach the router.
Note: The RouterID must be a router that has a direct link into
the backbone (Area 0).
Working with OSPF
18-9