Large-Scale IP Network Solutions (CCIE Professional Development)

Summary

This chapter discussed OSPF, which is a link-state protocol used as an IGP. There are five types of OSPF packets: hello, Database Description (DBD), request, update, and acknowledgment (ack). OSPF divides a large network into smaller subdomains, called areas. An area is a group of network segments and their interfaces. They are usually connected to each other by routers, creating a single autonomous system. There are four common types of areas in OSPF: regular, stub, totally stubby, and not so stubby (NSSA).

To enable OSPF in the global configuration mode, first define the network, and then assign those networks to specific areas. OSPF uses two types of configuration constants: fixed and configurable. There are four ways to configure ...