vate automatic branch exchange pulse code modulation personal digital assistant PDP (context) packet data protocol (context) personal digital communication packet data convergence protocol (fig 5.14) packet data protocol packet-data service node peer group peer group identifier peer group leader pretty good privacy per hop behaviour public key infrastructure public land mobile network private network-network interface point of interconnect post office protocol plain ordinary telephony service point-to-point protocol push proxy gateway point-to-point tunnelling protocol packet switching capability personal service environment management public-switched telephone network personal trusted device particular (fundamental) technical plans photonic cross-connect Quality of Service Quantitative assured media playback service RADIUS remote authentication dial-in user service ratio access bearer RANOS radio access network operation support radio base station request for comments Glossary xxvii routing information protocol radio link control radio network controller return on investment return on capital employed robust header compression ratio link control resource reservation protocol RSVP-TE RSVP - traffic engineering R-SGW roaming signalling gateway real time control protocol round trip delay real time protocol real time streaming protocol round trip time SIM application toolkit session description protocol supply chain management service control point service capability server stream control transmission protocol synchronous digital hierarchy service description protocol serving GPRS support node signalling gateway SHDSL single pair high bit rate digital subscriber line SIGTRAN signalling transport (working group) subscriber identity module session initiation protocol strategy, infrastructure and product service level agreement service level specification small and medium enterprise S/MIME secure multipurpose Internet mail extensions short message peer-to-peer protocol short message service simple mail transfer protoco