Design of SIPp-based IMPP client

Internet users are rapidly increased, and various services, which use Internet, are invented. Presence service is one of them. Most of products which have recently developed on presence and instant messaging services can't offer interoperability among each other. Now, people are focused on providing interoperability among different products. In this paper, the standard technologies for SIP-based presence service are introduced and system architecture and API s for SIP-based Presence services are described.