AIS AI2524 user manual Specify Router-Lev elSupport, Configure IS-IS Authentication Passwords

AI2524 Router Card User’s Manual

Specify Router-Lev elSupport

It is seldom necessary to configure the IS type because the IS-IS pro- tocol will automatically establish this. However, you can configure th AI2524 to act as a Le vel1 (intra-area) router, as both a Level1 router and a Leve l2 (interarea) router, or as an interarea router only.

In router configuration mode, configure the IS-IS level at which the router is to operate:

is-type {level-1 level-1-2 level-2- only}

Configure IS-IS Authentication Passwords

You can assign authentication passwords to areas and domains. An area password is inserted in Level 1 (station router) link-state PDUs (LSPs), complete sequence number PDUs (CSNPs), and partial se- quence number PDUs (PSNPs). A routi ng domainauthentication password is inserted in Leve l2 (area router) LSP, CSNP, and PSNP.

In router configuration mode, configure area or domain passwords:

1.Configure the area authentication password. area-passwordpassword

2.Configure the routin g domainauthentication password. domain-passwordpassword

Ignore IS-IS Link-State Packet (LSP) Errors

You can configure the router to ignore IS-IS LSPs that are received with internal checksum errors, rather than purging the LSPs. LSPs are used by the receiving routers to maintain their routing tables.

The IS-IS protocol definition requires that a received LSP with an in- correct data-link checksum be purged by the receiver, which causes the initiator of the LSP to regenerate it. However, if a network has a link that causes data corruption while still delivering LSPs with correct data-link checksums, a continuous cycle of purging and regenerating large numbers of LSPs can occur, rendering the network nonfunc- tional.

In router configuration mode, allow the router to ignore LSPs with an internal checksum error:

ignore-lsp-errors

Page 9-28	August 1997
	2524UM