3com 5500-ei pwr Installation Instruction
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OSPF Configuration
When configuring OSPF, go to these sections for information you are interested in:
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The term router in this chapter refers to a router in a generic sense or an Ethernet switch running a
routing protocol.
OSPF Overview
Introduction to OSPF
Open Shortest Path First (OSPF) is a link state-based interior gateway protocol developed by IETF. At
present, OSPF version 2 (RFC 2328) is used, which has the following features:
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High applicability: OSPF supports various networks in size, and even networks with up to several
hundred routers.
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Fast convergence: OSPF can transmit update packets immediately after the network topology
changes so that the change can be synchronized in the autonomous system (AS).
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Loop-free: Since OSPF calculates routes with the shortest path first algorithm according to the
collected link states, it guarantees that no loop routes will be generated.
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Area partition: OSPF allows an autonomous system network to be divided into different areas for
convenient management so that routing information transmitted between the areas is summarized
further, thereby reducing network bandwidth consumption.
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Equivalent route: OSPF supports multiple equivalent routes to the same destination.
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Routing hierarchy: OSPF has a four-level routing hierarchy. It prioritizes the routes as intra-area,
inter-area, external type-1, and external type-2 routes.
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Authentication: OSPF supports interface-based packet authentication to guarantee the security of
route calculation.
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Multicast transmission: OSPF supports transmitting protocol packets in multicast mode.