Ospf-Router; Link State Advertisement - Hirschmann MACH 4000 User Manual

OSPF

7.1.5 OSPF-Router

OSPF distinguishes between the following router types:
Interner Router:
Alle OSPF-Interfaces eines internen Routers liegen in der selben Area.
Area Border Router (ABR):
ABRs have OSPF interfaces in a number of areas, including the back-
bone area. ABRs thus participate in multiple areas. Where possible, you
summarize a number of routes and send "Summary LSAs" to the back-
bone area.
Autonomous System Area Border Router (ASBR):
An ASBR is located on the boundary of an autonomous system and links
OSPF to other autonomous systems / routing protocols. These external
routes are transferred into OSPF using what is known as redistributing
and are then summarized as "AS-external LSAs" and flooded into the
area.
Switch on the redistributing explicitly.
If you want to use subnetting, then you enter this explicitly. In OSPF, the
following "routing protocols" can be exported:
connected (local subnetworks on which OSPF is not switched on),
static (static routes),
RIP.

7.1.6 Link State Advertisement

As a basis for building up a database via the link states, OSPF uses Link
State Advertisements (LSA).
An LSA contains information about
the router,
the connected subnets,
the routes that can be reached,
the network masks and
the metrics.
Routing L3P
Release 4.0 11/07
7.1 OSPF-Topology
75