Ospf Fundamentals - Bay Networks NauticaRS Reference Manual

NauticaRS 5.5R Reference Guide

OSPF Fundamentals

18-2
Using RIP to route information does have limitations. RIP, for
example, only routes over a maximum of 15 routers or hops.
Often, in larger organizations, information needs to be routed
over distances greater than 15 hops. OSPF overcomes this and
many other RIP limitations.
OSPF is set-up around areas, with the central area (or backbone)
being the common link to all areas. The basic rule with OSPF is
that all the areas need to see the backbone (Area 0), but they do
not have to see each other.
The routers that link the various areas into the backbone are
known as Area Border Routers (ABRs). An ABR is a router that
can see at least two other areas (one of which must be the
Backbone).
OSPF can be divided into two distinct forms, Intra-Area OSPF,
where information is routed inside an area, or Inter-Area OSPF,
where information is routed between different OSPF areas.
In the table below, click on the topic for which you require further
information.
Intra-Area OSPF Inter-Area OSPF
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