Brocade Communications Systems ICX 7250 series, Руководство по настройке

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FIGURE 17 OSPF operating in a network
NOTE
For details of components and virtual links, refer to OSPFv2 components and roles on page 212 and Virtual links on page
219, respectively.
Once OSPFv2 is enabled on the system, the user assigns an IP address or number as the area ID for each area. The area ID is
representative of all IP addresses (subnets) on a router port. Each port on a router can support one area.
OSPFv2 components and roles
OSPFv2 can be configured on either a point-to-point or broadcast network.
Devices can take a variety of roles in an OSPFv2 topology, as discussed below.
Area Border Routers
An OSPF router can be a member of multiple areas. Routers with membership in multiple areas are known as Area Border Routers
(ABRs). All ABRs must have either a direct or indirect link to an OSPF backbone area (also known as area 0 or area 0.0.0.0). Each ABR
maintains a separate topological database for each area the router is in. Each topological database contains all LSA databases for each
router within a given area. The routers within the same area have identical topological databases. An ABR is responsible for forwarding
routing information or changes among its border areas.
For more information on OSPFv2 areas, refer to the OSPFv2 areas section.
Autonomous System Boundary Routers
An Autonomous System Boundary Router (ASBR) is a router that is running multiple protocols and serves as a gateway to routers
outside the OSPF domain and those operating with different protocols. The ASBR is able to import and translate different protocol routes
into OSPF through a process known as redistribution.
OSPFv2 components and roles
Brocade FastIron Layer 3 Routing Configuration Guide
212 53-1003903-04