Not quite sure about your question. Hope this help:
https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13697-25.html#authentication
Not quite sure about your question. Hope this help:
Note: The area authentication command in the configuration enables authentication for all the interfaces of the router in a particular area. You can also use the ip ospf authentication command under the interface to configure plain text authentication for the interface. This command can be used if a different authentication method or no authentication method is configured under the area to which the interface belongs. It overrides the authentication method configured for the area. This is useful if different interfaces that belong to the same area need to use different authentication methods.
Not quite sure about your problem. Hope this help:
Note: The area authentication command in the configuration enables authentication for all the interfaces of the router in a particular area. You can also use the ip ospf authentication command under the interface to configure plain text authentication for the interface. This command can be used if a different authentication method or no authentication method is configured under the area to which the interface belongs. It overrides the authentication method configured for the area. This is useful if different interfaces that belong to the same area need to use different authentication methods.
首先OSPF支持区域认证和接口认证。
R1-----R2-----R3-----R4
上边四台路由器假设都属于OSPF Area 1区域,都开启了OSPF密文区域认证
这个时候R2----R3开启了接口认证(接口明文认证或者接口密文认证也好)这个时候R2和R3的接口认证方式高于前边的区域认证。
cisco有个特点,就是在接口下做的配置要高于在进程下的配置。就打个比方,cisco的OSPF协议network你可以在全局创建OSPF进程进行宣告,也可以在接口下进行宣告
接口下宣告命令:R1(config-if)# ip ospf 100 area 0