3Com Switch 8800 Advanced Software V5 Configuration Guide

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OSPF CONFIGURATION
Open Shortest Path First (OSPF) is a link state based interior gateway protocol
developed by the OSPF working group of the Internet Engineering Task Force
(IETF). At present, OSPF version 2 (RFC2328) is used.
When configuring OSPF, go to these sections for information you are interested in:
■ “Introduction to OSPF” on page 301
■ “OSPF Configuration Task List” on page 321
■ “Configuring OSPF Basic Functions” on page 323
■ “Configuring OSPF Area Parameters” on page 324
■ “Configuring OSPF Network Types” on page 325
■ “Configuring OSPF Route Control” on page 327
■ “Configuring OSPF Network Optimization” on page 330
■ “Displaying and Maintaining OSPF Configuration” on page 337
■ “OSPF Configuration Examples” on page 337
■ “Troubleshooting OSPF Configuration” on page 350
n
The term "router" in this document refers to a router in a generic sense or an
Ethernet switch running routing protocols.
Introduction to OSPF
n
Unless otherwise noted, OSPF refers to OSPFv2 throughout this document.
OSPF has the following features:
■ Wide scope: Supports networks of various sizes and up to several hundred
routers in an OSPF routing domain.
■ Fast convergence: Transmits updates instantly after network topology changes
for routing information synchronization in the AS.
■ Loop-free: Computes routes with the shortest path first (SPF) algorithm
according to the collected link states, so no route loops are generated.
■ Area partition: Allows an AS to be split into different areas for ease of
management and the routing information transmitted between areas is
summarized to reduce network bandwidth consumption.
■ Equal-cost multi-route: Supports multiple equal-cost routes to a destination.
■ Routing hierarchy: Supports a four-level routing hierarchy that prioritizes the
routes into intra-area, inter-area, external type-1, and external type-2 routes.