link state packet (LSP)
A link state packet ( LSP) is a data packet with which network topological information is transmitted. The LSP packets are generated by a router using the link state algorithm and list the neighboring routers. The link state database for this routing area is obtained from all link state packets generated by all routers in a routing area. The routers use the link state packets to monitor the network topology and enter changes directly into the link state database. The network topology is monitored either by flooding the LSP data packets or by confirmation procedures.
The Link State Packet is one of four message types used in the Intermediate System to Intermediate System Protocol( IS-IS).