ABSTRACT
This part introduction presents an overview of the key concepts discussed in the subsequent chapters. The part examines the technological details of OSPF and IS-IS. It aims to give the reader enough information so that he/she can fully operate real life OSPF and ISIS networks. The part explains the Link State Database (LSDB) structure of OSPF and IS-IS for the case of single-area networks. It introduces the synchronization mechanisms required to keep the LSDB updated and synchronized. The part discusses the extensions for the support of hierarchical routing. OSPF and IS-IS are the main Link State Routing players in today’s Internet. They are implemented by virtually all vendors of routing equipment and have been widely deployed in most large IP networks worldwide. When comparing the IPv4 and IPv6 versions of each technology, the main differences are in the LSDB structure. The synchronization mechanisms are essentially the same within a given technology.
