How to Configure OSPF Plain Text Authentication

Lessons Discussion
21

does OSPFv2 do the encryption or only ospfV3 does ??

22

Hello Narad

OSPFv2 does use MD5 for encryption of the authentication process. You can find out more here:

In addition, OSPFv2 based on RFC 2328 allows only MD5, but RFC 5709 has added the use of HMAC-SHA algorithms for cryptographic authentication.

As for OPSFv3, it supports authentication with IPsec. You can find out more about that here:

I hope this has been helpful!

Laz

23

Hi,

Does this always have to be configured per interface in OSPF or is there a command to configure it for the entire area in router ospf [proccesid] mode?

Thanks!

24

Hello Cameron

The enabling of the feature can either be done globally (per area on a router) or on a per-interface basis. Per interface, the command is:

R2(config)#interface fastEthernet 0/0
R2(config-if)#ip ospf authentication

Globally, the command is:

R1(config)#router ospf 1
R1(config-router)#area 0 authentication

Now the configuration of the authentication key must be done on a per-interface basis. This is because you may have a different keys for different neighbors that are connected to different interfaces. This command can only be applied to the interface like so:

R1(config)#interface fastEthernet 0/0
R1(config-if)#ip ospf authentication-key MYPASS

I hope this has been helpful!

Laz

25

Thank you for the clarification. It helped me a lot!

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