IS-IS Network Design Solutions

Sequence Number Packets

Link-state packets and their relevance to the process of gathering and disseminating routing information within the IS-IS protocol is covered, in detail, in the preceding section. This section discusses SNPs, which are used in auxiliary mechanisms that ensure integrity of the LSP-based routing information distribution process. You might recollect that hello packets establish and maintain adjacencies between neighbor routers, whereas LSPs are the vehicles for sharing routing information. In a link-state routing environment, routers in an area receive the LSPs from all other routers in the area through their directly connected neighbors in a process called flooding. Through flooding, routers in an area build identical (synchronized) ...