| Recently, networks technology,embedded technology,computer technology and multimedia communication technology having develop rapidly, the 3G license had issues to three domestic telecom operators in 2009, and deploying the 3G networks in full preparation. SIP protocol is a network communication signaling protocol, which is one of the signals protocol to develop VoIP network telephone, it is specified by IETF, and widely used around the world, because of easy control. Since VoIP network telephone invention, because the less cost of phone call, high intelligent, nice tone quality, easy network deployment and etc, VoIP phone has caused wide public concern, and loved by lots of people, especially the enterprise user, but has also brought formidable challenges to the traditional communication techniques. This topic developed and accomplished arm platform embedded VoIP network telephone, which is combining the embedded technology and the SIP network telephone communication technology.This paper deep analysis network telephone technology evolution, fully discuss the network telephone relative protocol, such as SIP,H.323,SDP protocol etc. Especially discuss SIP signaling protocol technologies and the implementation method. This topic accomplish the whole construct of the embedded platform, which is based on the underlying hardware platform of arm9 core S3C2440 CPU, and use the u-boot underlying bootstrap program, construct embedded linux operating system and yaffs2 root file system. Used the PJSIP protocol as the VoIP network telephone communication signaling protocol, fully introduce the design model of the PJSIP and how to use, and developed the VoIP software terminal. Then used embedded Qt4 as the GUI develop suit kit, port to the arm9 develop platform, and designed friendly VoIP telephone man-machine interaction GUI, facility the use of the software. The test results indicate that embedded VoIP terminal basically accomplish the communication of SIP signaling, and can have a voice communication with each other. |
