Study Of Embedded Home Gateway Based On SIP Protocol

With the promoting of standard of living and continuous seeking for our habitation,Intelligent Home will become one of obligatory need in our future life. The study of Home Gateway will become one of hotspot in the whole World,which is for that Home Gateway is the core in the communication between inside and outside of the Intelligent Home.Besides that,Home Gateway is a carrier of long-range control,video monitor,multimedia communication and so on.The question of that the terminals of different standards are unable to access to the Home Gateway is aimed in the paper.The solution of it is proposed in the paper, and which is to use Home Gateway in p2p environment.The resource of the smart cell can be shared by the solution.The routing algorithm is optimized and the robustness study of Home Gateway in p2p surrounding is raised in the paper.The embedded development process is adopted as the total development program.The development board of QQ2440V3 is adopted as substrate.The cutting and transplantation is achieved in development board,Linux system,and application software,which realize the hardware and software platform of the Home Gateway.Numerous study works are done to realize the embedded Home Gateway based on SIP protocol:(1) The SIP protocol which is accorded great importance by IETF and 3GPP is pulled into Home Gateway based on the comparison to H.323.The next core network and 3G network will be switched into by SIP protocol.The rich multimedia functions will be supported by using SIP protocol.The new function will be achieved by expanding the information packet header,which raises the expansion of Home Gateway.(2) The Chord arithmetic is pulled into Home Gateway to switch in non-standard SIP terminal and share resources in intelligent subdistrict.The Chord Loop is formed by Home Gateway.The SDRAM of Home Gateway is used to store the information aboat the terminal of intelligent home and sharing of intelligent subdistrict, which is applied to realize the locating and communication of different standard terminals.(3) The Zigbee protocol is applied to design the module of wireless,which will be convenient to install terminals.The Zigbee is more superior Bluetooth technology. The wired and wireless terminals can be switch flexibly in Home Gateway,which will promote the experience of users.(4) The RADIUS and iptables are transplanted to ARM,which promote the security of Home Gateway by coordinating with encrypted transmission of SIP protocol.(5) The SIP protocol is come ture by OpenSER in the paper.The OpenSER and RADIUS are fused by altering the configuration of them,which brings aboat the integration of RADIUS,OpenSER,and Mysql.(6) The question which is how the different standard terminals switch in and how the resources will be shared is resolved by the P2P solution of Home Gateway.The Home Gateway is used in new and complex environment and the new research content of robustness is raised.The relative robustness mechanism is studied and designed,which promote the robustness of intelligent home and intelligent subdistrict.The hardware and software platform are designed for the Home Gateway based on total architecture in the paper.The hardware platform is designed again on the basis of QQ2440V3.The module of Internet is improved and the CS8900a is replaced of DM9000,which lets the reticle of 100Mbits/S can be pulled into the Home Gateway.The requirement of multimedia communication and digital TV will be met by the improvement of Internet module.The wireless module of Zigbee is mainly developed in the hardware platform.The module is realized by MC13193 and MC9S08GT60,which is produced by Freescale.The module is directly attached to MCU by serial prot and the Zigbee protocol stack need not be designed by yourself, which cuts down the research period and reduces the cost.The software platform is achieved by embedded system and application software and the application software is mainly studied.The embedded system is realized by cutting out and ARM transplantment of bootloader,system kernel,and root filesystem.The OpenSER protocol stack,RADIUS module,and Chord arithmetic are included in the development of software platform.The SIP protocol is achieved by OpenSER,which provides the carrier for the multimedia communication.The security is raised by RADIUS module and the integration of RADIUS,OpenSER,and Mysql is realized by altering configuration file.The Chord arithmetic is realized by SHA-1 arithmetic and it is the sticking point to achieve P2P network for Home Gateway.The function module is designed and communication mechanism is researched in the paper.The Home Gateway is used in P2P environment for switching in different standards of terminals,which let the robustness of Home Gateway has new feature. Four fields are included in the study of robustness for the Home Gateway in the paper: the robustness of external connection,divertion and backuping the resources of Home Gateway,the updating of three tables for Chord arithmetic,the optimization of routing arithmetic for Chord arithmetic.The terminal information can be routed by the study of robustness aboat external connection,which can prevent the interruption of link;The information of non-standard SIP terminal and the sharing information aboat intelligent subdistrict can be effectively protected by the mechanism of divertion and backuping for resources when the Home Gateway is restarted;The three tables of Chord arithmetic are point to FingerTable,ReverseFingerTable,Successor-Table. The crucial effect of FingerTable is embodied when the information is routed. The ReverseTable and SuccessorTable will be used on the time of divertion and backuping for resources.The updating of FingerTable and ReverseTable is triggered by event in the paper and the refreshening of SuccessorTable is achieved by the parameter of heartbeat.The variation of network topology for Chord is reflected by updation of three tables for Chord arithmetic,which will determine the location, calling,and session between the terminals;The quantum of information for Home Gateway is vary large and the speed of route is the embodiment for rebustness.The route arithmetic of Full Chord is pulled into the paper by using FingerTable and ReverseFingerTable,which promotes the routing efficiency nearly 50%than the original Chord arithmetic.The function tests are done for validating the functions of Home Gateway which is designed in the paper.The pictures aboat three typical function tests are intercepted: the voice session between standard SIP terminals,the video session between standard SIP terminals,and three-part conference between different standards of terminals.The requests which raised at the study plan are satisfied in the Home Gateway,which is proved by the function tests.The Home Gateway designed in the paper can resolve the question that different standards can not be switched into Home Gateway and supports the communication for mutilmedia.The embedded Home Gateway based on SIP protocol is actually used in Hangzhou and the result is good.The merits of the embedded Home Gateway based on SIP protocol includes:(1) The P2P solution for Home Gateway is raised and the Chord arithmetic is pulled into intelligent subdistrict to realize the Chord Loop for Home Gateway.The question that different standards of terminals can not be switched into original Home Gateway is settled and the sharing of resources in intelligent subdistrict can be brought aboat in the paper.(2) The new features of robustness which are embodied in P2P environment are proposed in the paper and the related robustness mechanism is studied.The question of that the terminals of different standards are unable to access to the Home Gateway is resolved by Embedded Home Gateway Based on SIP Protocol. The multimedia communication is supported in it and it has expansion,high security and high robustness.The Home Gateway designed in this paper is verified by experiment and examed by actual use.There is economic significance and social significance in the designed Home Gateway in the paper.