HP Routing Services -UX 11i v2 manual Areas Defined in an Autonomous System, Network Router Area

Figure 3-3

Configuring gated

Configuring the OSPF Protocol

Areas Defined in an Autonomous System

Area 1

A

2

Area 2

1

B

3

F

4 G

C D

E

Area 3

5 H

Other AS

I

6

Legend:

Network

Router

Area

Backbone

Internal routers have all their directly connected networks in the same area. In Figure 3-3, routers A, B, and H are internal routers.

Routers that are connected to multiple areas are called area border routers. In Figure 3-3, routers F and G are area border routers.

Routers that connect one AS to another are called AS boundary routers. In Figure 3-3, router D is an AS boundary router.

Neighbor routers are routers that interface to a common network. OSPF uses its own Hello subprotocol to determine which routers are neighbors. In Figure 3-3, routers A, B, and C are a set of neighbor routers that interface to network 1, while routers A and F are another set of neighbor routers that interface to network 2.

NOTE	The Hello subprotocol used with OSPF is not the same as the gated
	HELLO protocol. The Hello subprotocol is still supported.

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