Configuring OSPF
PR2000 Installation Guide
63
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Router ID. Enter the OSPF router ID. Every router in an OSPF
network needs a unique ID. This is normally the IP address of one
of the router interfaces.
•
This is an AS boundary router. An Autonomous System
Boundary Router (ASBR) can import and advertise external routes.
If you configure the router as an ASBR, you will also be asked to
configure the parameters that specify which routes are to be
imported by OSPF (non-OSPF interfaces, static routes, and RIP
routes).
The Area menu allows you to configure area-specific parameter such as
password and network range condensation.
•
Area ID. Because a router can belong to different areas, first you
are asked to identify the area you want to configure.
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Authentication Type. The PR2000 supports both OSPF networks
without authentication and OSPF networks with simple password
authentication. The authentication type should be the same for all
routers in an OSPF area. If used, the password for each interface is
configured in the per-interface OSPF configuration.
•
Stub Area. The backbone area cannot be a stub area. So, this
question will be presented if you are configuring areas other than
the backbone. Areas that are connected to the backbone through
only one border router can be configured as “stubs” . A stub is an
area where all the external routes are summarized by a “default”
route. If you configure an area as a “stub” area, you also need to
enter the metric for routing through this default route.
•
Area Ranges. OSPF Area Border Routers (ABR) link state
advertisements for all the networks in the area. You can potentially
reduce the number of such advertisements by condensing different
IP networks into a single range.
The Neighbors configuration is required if the router uses OSPF over NBMA
(non-broadcast multi-access) interfaces such as X.25 and Frame Relay. It lets
you configure the IP address and status of the neighbor.
Virtual Links allows you to configure OSPF virtual links. The parameters are:
•
Transit Area. Identifies the transit area configured by this virtual
link. The area ID is entered in dotted decimal notation.
•
Neighbor’s ID. Identifies the interface at the other end of the virtual
link. This router must be in the transit area specified above.
