2[2]Radvision,SIP server technical overview[EB/OL],http://www.sipforum.org,2005.
3[5]Cisco systems,SIP:the next step in converged IP communications[EB/OL].http://www.cisco.com,2004.
4[6]HAVERINEN H,SALOWEY J.RFC4186,Extensible Authentication Protocol Method for Global System for Mobile Communications(GSM)Subscriber Identity Modules(EAP-SIM)[S].
5[7]ARKKO J,HAVERINEN H.RFC4187,Extensible Authentication Protocol Method for 3rd Generation Authentication and Key Agreement(EAP-AKA)[S].