Compatible Systems 5.4 manual Ospf 259 Ospf Area Name, Ospf Authentication Type, Enable Stub Area

Chapter 15 - OSPF 259

OSPF Area Name

The OSPF Area Name is an integer or IP address. If more than one area is configured within an AS, then one of these areas has to be area 0, which is the backbone. The backbone has to be physically connected to all other areas. It is recommended that you start with area 0 and then expand into other areas.

ϖNote: The only exception to starting with area 0 is with virtual links, which are explained in the following section.

OSPF Authentication Type

This pull-down box specifies whether the router will perform authentication of Link State Advertisements received from other routers.

•If Simple is selected, you must specify an authentication key for any interface which is associated with this area.

•If None is selected, no authentication will be done on Link State Adver- tisements.

Authentication Key

This sets the OSPF packet authentication key. The authentication key must match for each router connected to the interface and belonging to the area. The authentication key must be between one and eight alphanumeric charac- ters.

Enable Stub Area

This checkbox sets whether this area will function as a stub area. A stub area is an area which cannot receive external advertisements, which means RIP or static routes will not be redistributed into this area.

If routing from a stub area to external routes (i.e., non-OSPF routes) is needed, a default route must be set. A stub area may not be a transit area for a virtual link.

ϖNote: The backbone area (area 0) cannot be designated as a stub area.

Stub Default Cost

This value sets the cost of the default route which will be used by routers within the stub area to route to external destinations. The value must be a number between 0 and 65,535.

Net Range

The Net Range can be used to consolidate routing information at area bound- aries, or to hide routing information from routers outside the area. Net Ranges only apply to inter-area networks. If all the routers are in one area, any defined Net Ranges will not be used by the router. You may specify several different Net Ranges.