Sanjeev Sawai Vice President Research Development Envox Worldwide

Sanjeev Sawai Vice President, Research & Development Envox Worldwide The Role of SIP in IMS PROPRIETARY AND STRICTLY CONFIDENTIAL

Agenda • • • 2 IMS Defined SIP Background SIP within IMS The SIP Advantage IMS-specific SIP enhancements PROPRIETARY AND STRICTLY CONFIDENTIAL

IMS Defined • IMS is a standard architecture for deploying IP-based multimedia applications on a common infrastructure that is independent of the access network • IMS enables service providers to roll out new services rapidly and deliver them to any device over any network • IMS is the glue between the service/application layer and the network/media layer 3 PROPRIETARY AND STRICTLY CONFIDENTIAL

The IMS Promise • Ubiquitous access to all rich services available on the Internet from handheld devices via wireless and wireline networks – Voice, video, web, email, IM, IPTV • IMS standards enable convergence of the Internet and telephone networks 4 PROPRIETARY AND STRICTLY CONFIDENTIAL

IMS Functions • User authentication and security • Quality of service, prioritization for different applications • Application development benefits from standardization of interfaces and components 5 PROPRIETARY AND STRICTLY CONFIDENTIAL

SIP Background • Text based client/server protocol used to create sessions in an IP network – Enables simple two-way calls through multi-media conferencing solutions • Extensible protocol enables support for new applications • Widely accepted by the Internet community 6 PROPRIETARY AND STRICTLY CONFIDENTIAL

The Role of SIP in IMS • SIP is the basis of IMS • SIP is the protocol for session control and communication between the service, control and media planes • SIP proxy servers (x-CSCF) are critical elements of the IMS network 7 PROPRIETARY AND STRICTLY CONFIDENTIAL

Call Session Control Function • Proxy-CSCF P-CSCF – SIP proxy that is the initial interface in a visited network – Security, authorization and translation • Serving-CSCF S-CSCF I-CSCF 8 PROPRIETARY AND STRICTLY CONFIDENTIAL – SIP server within the IMS signaling plane – Controls sessions and registrations; triggers and executes services • Interrogating-CSCF – SIP Proxy – Deals with registration, routing and forwarding of SIP messages and charging

The SIP in IMS Advantage • SIP is currently the basis of session control for many Internet services – Vo. IP, conferencing, video calls, presence management, IM • SIP provides IMS with provencall/session control capabilities on the IP network • Enables the IMS goal to provide ubiquitous access to all existing and future Internet services • Enables users to combine multiple services from different vendors to form entirely new services 9 PROPRIETARY AND STRICTLY CONFIDENTIAL

SIP Requirements for IMS • • 10 Private SIP headers IPv 6 support Compression for signaling between UE and P-CSCF Support for IM URI, PRES URI, and TEL URI Translation between TEL URI to SIP URI HTTP DIGEST using 3 GPP AKA Authentication IPsec - IP security PROPRIETARY AND STRICTLY CONFIDENTIAL

Summary • There is no IMS without SIP 11 PROPRIETARY AND STRICTLY CONFIDENTIAL