3Com 10014299 manual Configure Authentication, Key-id

436 CHAPTER 29: CONFIGURING OSPF

■ dead-timer: 40 seconds

Configuring OSPF supports simple text authentication and MD5 authentication between Authentication adjacent routers.

Perform the following configurations in interface view.

Table 502 Configure Authentication

Operation	Command
Specify a password for OSPF simple text	ospf authentication-mode simple
authentication	password
Specify the string and key-id for OSPF	ospf authentication-mode md5 string
MD5 authentication	key-id
Cancel authentication on the interface	undo ospf authentication-mode

By default, the interface does not authenticate OSPF packets.

The maximum length of a password for plain text authentication is 8 characters and for a MD5 string authentication the maximum length of the password is 16 characters. The key-idattribute is the key value of MD5 authentication, ranging from 1 to 255.

Note that the configured packet authentication mode, authentication password, and the key-id on the router interface in the same network segment must be consistent.

Configuring Route The dynamic routing protocols on the routers can share routing information. Due Import for OSPF to OSPF features, the routes found by other routing protocols are always regarded

as the routes outside the AS in processing. In the receiving command, the cost type of the route, cost value, and flag can be specified to overlap default routing parameters.

OSPF uses 4 different route types, whose sequence runs:

■Intra-area route — The route in an area of the AS.

■Inter-area route — The route between different areas of the AS.

■External router Type 1— The received IGP route (such as RIP, STATIC). The reliability of this route is high, so the calculated cost of the external route and the cost of the route inside the AS are in the same numeric level. It is comparable with the cost of OSPF route, i.e. the cost value of external route Type 1 = the cost value from the local router to the corresponding ASBR + the cost value from ASBR to the destination address of the route.

■External router Type 2 — The received EGP route. Due to the concerns of poor reliability of this route, the OSPF protocol considers the cost from the ASBR to outside the AS as much as, or more than, the cost to the ASBR within the AS. Therefore, mainly the former is considered in the calculation of route cost, i.e. the cost value to the external route Type 2 = the cost values from the ASBR to the route destination address. If the values are equal, consider the cost value from the local router to the corresponding ASBR.

Perform the following configurations in OSPF view.