Owner's Manual

Chapter 25. OSPFv3 | 688
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25. OSPFv3
This chapter includes the following sections:
• Overview on page 688
• Route Redistribution on page 693
• OSPFv3 Configuration Example on page 694
Note: OSPFv3 is available on platforms with an Advanced Edge or Core
license. See
Appendix A, XCM8800 Software Licenses for
information about OSPFv3 licensing.
Overview
Open Shortest Path First (OSPF) is a link state protocol that distributes routing information
between routers belonging to a single IP domain; the IP domain is also known as an
autonomous system (AS). In a link-state routing protocol, each router maintains a database
describing the topology of the AS. Each participating router has an identical database for an area
maintained from the perspective of that router.
From the link state database (LSDB), each router constructs a tree of shortest paths, using itself
as the root. The shortest path tree provides the route to each destination in the AS. When
several equal-cost routes to a destination exist, traffic can be distributed among them. The cost
of a route is described by a single metric.
OSPFv3 supports IPv6, and uses commands only slightly modified from that used to support
IPv4. OSPFv3 has retained the use of the 4-byte, dotted decimal numbers for router IDs, LSA
IDs, and area IDs.
OSPFv3 is an interior gateway protocol (IGP), as is the other common IGP for IPv6, RIPng.
OSPFv3 and RIPng are compared in
Chapter 23, RIPng.