Identifying IPSec Peers

IPSec requires the exact method of peer identity used for a session. There are two ways to identity a peer: via its fully qualified domain name (FQDN) or via an IP address. To configure the method of peer identity, we would issue the command:

 R1 (config)# crypto isakmp identity {address | hostname} 

The default is for the IOS-based router to identify its peer by IP address.