Research And Implementation Of Embedded Terminal Based On SIP

With the rapid development of Computer and Internet technology,the combination of embedded and network communication has been attracted more and more attentions.VoIP is a digital voice transfers technology based on IP networks, which identified by voice packet-switch.Embedded VoIP terminal will be an important application of embedded system.SIP protocol is the most widely used signaling control protocol in VoIP system, which is rapidly adopted by the telecommunications industry to build the next generation of applications.SIP is an application-layer control protocol that can establish,modify,and terminate multimedia sessions or conferences.VoIP technology which is based on SIP is becoming a hot area of research.This thesis researches a method to implement a embedded terminal which is based on SIP.The main contributions in this thesis are as follows:1.The thesis studies on the architecture of hardware and software systems,that is, taking S3C2410 ARM chip as the core controller and Linux operating system as software platform.2.This part discusses VoIP key technologies and studies the architecture, realization,message mechanism and signaling flow of SIP.3.Based on the theory of embedded system and combined with characteristics of Linux,the scheme based on Linux is proposed and development environment based on the embedded system is formed.In this thesis take a PC with Redhat9 to be the host.Cross-compile toolchains are installed on the host to construct cross-compile environment.The content structure,booting sequence and the difficulty of vivi porting are analyzed and vivi is ported successfully to the embedded system.The characteristics of Embeded Linux kernel,content structure are analyzed,and the kernel is ported successfully.According to the system requirement,based on busybox file system is constructed.4.In the third parts,the thesis researches the structure of oSIP protocol stack and Parser module,Finite State Machine module,and Facilities module.Propose the system structure of embedded SIP terminal and implement embedded SIP terminal based on oSIP protocol stack.At last,The thesis tests and analyses for the system after design on the SIP telephone terminal.The result shows that VoIP terminal, which is based on sip,achieves the requirements for all functions in this design and compliances with RFC3261 standards.