ion Internet Draft Internet Engineering Task Force Internet Message Access Protocol Internet Protocol IPSec Internet Protocol Security IPTEL IP Telephony Instant Messaging and Presence Protocol IMT-2000 International Mobile Telecommunications 2000 Intelligent Network Intelligent Network Application Protocol INRIA Institut National de Recherche en Informatique et en Automatique Internet Research Group Acronyms Integrated Services Digital Network Internet Society ISDN User Part International Telecommunication Union ITU-T International Telecommunication Union Telecommunication Standardization Sector INRIA Videoconferencing System Kilobits per second Local Area Network Lightweight Directory Access Protocol Multipoint Control Unit Multipurpose Internet Mail Extensions Media Gateway Media Gateway Controller Media Gateway Control Protocol Multimedia Conference Control MMUSIC Multiparty Multimedia Session Control Mobile Switching Center Multimedia Terminal Adapter Network Control Protocol Network Call Signalling Private Branch Exchange Pulse Code Modulation Portable Document Format P-CSCF Proxy-Call/Session Control Function Per Hop Behavior PSTN and Internet Interworking Acronyms Presence and Instant Messaging Public Switched Telephone Network Presence User Agent Quality of Service Request for Comments Request for Information Request for Products ReSerVation Protocol Real-time Transport Control Protocol Real-time Transport Protocol Real-time Streaming Protocol Session Announcement Protocol Simple Conference Invitation Protocol Service Control Point S-CSCF Serving-Call/Session Control Function Stream Control Transmission Protocol Session Description Protocol SDPng SDP next generation Signalling Gateway SIMPLE SIP for Instant Messaging and Presence Leveraging Extensions Session Initiation Protocol Service Location Protocol S/MIME Secure/Multipurpose Internet Mail Extensions Simple Mail Transport Protocol Signalling System no. 6 Signalling System no. 7 Acronyms Service Switching Point Standard Transmission Control Protocol 