IS-IS ISO Address

As IS-IS is protocol independant - sits at the data link layer, a non-ip address is used for routerid.

An ISO address is between 8 and 20 octets.

Address is broken into two sections (IDP/DSP), and is broken into three parts:

Area- group or location
ID - particular member of location
SEL - process on the host

IDP (interdomain part) External routing to AS, provided by ISO
- AFI - country code/international code/private
- IDI - organisation within the AFI
DSP (Domain Specific Part) - Internal routing within AS
- HODSP - area within AS
- System ID - might be based on IP or MAC address (cisco 6 bytes)
NSEL - Network Entity title 0x00