Research And Realization Of Instant Communication Based On SIP

In the paper, the idea that SIP is applied to the instant communication in network is presented through learning the knowledge about VoIP, analysing the abroad and domestic development situation of VoIP and Studying the SIP that is the most popular protocol about signal control now.SIP stands for Session Initial Protocol. It can build, hold and stop the session. To negotiate the media arguments with the other, SDP that stands for Session Description Protocol is used. The system uses the MS multimedia development kit to gather and broadcast the voice data that is divided and merged to be transported in network. To ensure the voice transported instantly, RTP is also used. Because of NAT, the STUN is used to solve the problem. The realization and use of the protocols is introduced in the paper that also describes the realization of the system.