Research And Design Of Embedded SIP Server Based On ARM9

SIP, Session Initiation Protocol, was initially proposed by IETF as an IP phone signaling protocol. It has been playing an important role in many fields including VoIP, soft switch, NGN and 3G.SIP, as one of the most important protocols since HTTP and SMTP, leads the trend of computer network and telecommunication. Now more carriers and VoIP providers are providing service based on SIP. Furthermore, network device providers are developing hardware supporting SIP signaling. Shenyang institute of computer applications of Chinese academy of sciences and the institute of computer science technologies of Beijing University have done some efforts and got much achievement.However, SIP is not mature enough. It's important and necessary for us to study its implementation, security and efficiency. Under this situation, based on a project of building the real-time voice communication platform in an e-government system, the paper conducts the study of SIP and the design of an embedded SIP server based on S3C2410. This task of the paper is as follows.1st, deep research on SIP architecture including SIP Protocol, message mechanism, signaling flow and some other critical technique, such as registering process and reliability. After the analysis of the mechanism of SIP security and its authentication, the paper then provides the improvement of SIP's HTTP digest authentication.2nd, according to the users' demand analysis, the paper builds the hardware platform with S3C2410, which is of ARM9 architecture. The paper ports Linux 2.6 to S3C2410, and implements SIP protocol and SIP server. In the end, to meet the user requirements, the paper designs B/S management and online-updating program, which greatly increases its value.3rd, the paper also optimizes embedded Linux system and application according to the system hardware and software platform in various ways, which greatly improves its speed and efficiency.The embedded SIP server, which is based on ARM9 CPU, runs well in an e-government system as an important part of the LAN real-time voice communication platform. It is good for application in any other area.