Know your gear
Cisco Unified Presence supports interdomain federation over the SIP protocol with the AOL SIP Access Gateway (SAG). SIP federation with AOL enables Cisco Unified Presence users to federate with the following users: users with AOL public communities, for example, aim.com, aol.com, users of an enterprise whose domain is hosted by AOL, users of a foreign enterprise that federates with AOL, Cisco Unified Presence could use AOL as a clearing house to federate with these foreign enterprises.