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OSPFv2 is a compatible upgrade to OSPF. It involves enhancements to
protocol message authentication, and the addition of a
point-to-multipoint interface which allows OSPF to run over
non-broadcast networks, as well as support for overlapping area ranges.
When using OSPF, you must organize your network (i.e., autonomous
system) into normal, stub, or not-so-stubby areas; configure the ranges of
subnet addresses that can be aggregated by link state advertisements; and
configure virtual links for areas that do not have direct physical access to
the OSFP backbone.
- To implement OSPF for a large network, you must first organize the
network into logical areas to limit the number of OSPF routers that
actively exchange Link State Advertisements (LSAs). You can then
define an OSPF interface by assigning an IP interface configured on
this router to one of these areas. This OSPF interface will send and
receive OSPF traffic to neighboring OSPF routers.
- You can further optimize the exchange of OSPF traffic by specifying
an area range that covers a large number of subnetwork addresses. This
is an important technique for limiting the amount of traffic exchanged
between Area Border Routers (ABRs).
- And finally, you must specify a virtual link to any OSPF area that is not
physically attached to the OSPF backbone. Virtual links can also be
used to provide a redundant link between contiguous areas to prevent
areas from being partitioned, or to merge backbone areas.

Configuring General Protocol Settings

To implement dynamic OSPF routing, first assign VLAN groups to each
IP subnet to which this router will be attached, then use the OSPF /
General Configuration menu to enable OSPF, assign an Router ID to this
device, and set the other basic protocol parameters.
Command Attributes
General Information –
OSPF Routing Process – Enables or disables OSPF routing for all IP
interfaces on the router. (Default: Disabled)