This article proposes a new NAT and firewall traversal protocol called Session Layer Protocol for P2P-SIP system.

We propose a top-down design approach which specify desired global behaviors with a conversation protocol,after we analyzed the drawback of the bottom-up approach,and then verify whether the global protocol satisfy the preset system goals.

On the basis of analysis of features of Web service,this paper takes the example of BPEL4WS language to introduce the conversation protocol based on colored Petri net and corresponding method for Web composition service designing.

The notion of conversations,and their associated conversation protocols,as abstract representations to be used to characterize interaction between agents has been discussed in the agent community for several years now.

To solve the problem of Session Initiation Protocol(SIP) traversing Network Address Translator(NAT),this paper describes a new method based on port detection.

The design of a CDMA based wireless IP Phone terminal using SIP(session initiation protocol) upon the OMAP5912 platform was discussed,under the background of a vehicle electronic multi-media video and audio system.

11b wireless network interface cards in ad hoc mode can have the group communication ability by implementing MSR on network layer and using SIP signaling to control the communication.

By analyzing the problems while implementing SIP in mobile communication system,necessity of Signaling Compression(SigComp) is indicated.

Session Initiation Protocol (SIP) is a control protocol carrying on application layer used for multimedia communications at IP network that is proposed and supported to study by the IEEE.