SIP論文
6.9萬(wàn)字 92頁(yè)



摘 要
隨著網(wǎng)絡(luò)技術(shù)和多媒體技術(shù)的不斷發(fā)展，多媒體通信業(yè)務(wù)逐漸在Internet應(yīng)用中占據(jù)主導(dǎo)地位，其中以VOIP技術(shù)的應(yīng)用尤為突出。VOIP即基于IP網(wǎng)絡(luò)的語(yǔ)音通信，它不僅是狹義上的IP電話，更是一個(gè)能提供包括視頻交互在內(nèi)各種多媒體業(yè)務(wù)的綜合性應(yīng)用平臺(tái)。
VOIP系統(tǒng)一般基于SIP或H.323兩種通信控制協(xié)議。SIP協(xié)議具有結(jié)構(gòu)簡(jiǎn)潔、易于擴(kuò)展和適于Internet接入等良好的特性，它可以有效地控制媒體網(wǎng)關(guān)，控制PC呼叫。在軟交換技術(shù)即將成為下一代網(wǎng)絡(luò)交換技術(shù)的大背景下，SIP以其諸多優(yōu)勢(shì)被認(rèn)為可作為軟交換技術(shù)的接入層核心協(xié)議，并被成功應(yīng)用于諸多電信運(yùn)營(yíng)商的代表性系統(tǒng)中。
基于上述情況，我們進(jìn)行了Windows平臺(tái)上基于SIP的多媒體網(wǎng)絡(luò)系統(tǒng)構(gòu)架的研究。SIP多媒體網(wǎng)絡(luò)包括SIP多媒體終端和SIP服務(wù)器的實(shí)現(xiàn)。其中SIP終端的研究工作包括SIP協(xié)議棧、視音頻流的編解碼以及RTP傳輸。本文在論述研究工作的同時(shí)也介紹了一些相關(guān)的背景知識(shí)如SIP協(xié)議的框架、VOIP和可視電話的發(fā)展歷史等。
本文重點(diǎn)論述了Windows平臺(tái)SIP多媒體終端的實(shí)現(xiàn)，包括SIP協(xié)議棧的實(shí)現(xiàn)、視音頻流的采集、編解碼和網(wǎng)絡(luò)傳輸方案、SIP終端的工作流程、以及編解碼器基于指令集的優(yōu)化。同時(shí)介紹了常用視頻會(huì)議系統(tǒng)的結(jié)構(gòu)、論述了軟交換體系中SIP協(xié)議的重要性，以及對(duì)SIP與H.323標(biāo)準(zhǔn)作了各方面的比較。在第一章中先介紹了視頻會(huì)議系統(tǒng)的發(fā)展歷史和框架結(jié)構(gòu)，概述了作者的研究工作。第二章主要論述了SIP協(xié)議的結(jié)構(gòu)和SIP網(wǎng)絡(luò)的模型；針對(duì)SIP的優(yōu)勢(shì)將之與H.323標(biāo)準(zhǔn)作了比較，然后結(jié)合軟交換網(wǎng)絡(luò)論述了SIP的應(yīng)用前景。在第三章中詳細(xì)論述了SIP終端的實(shí)現(xiàn)方案，包括各部分模塊的實(shí)現(xiàn)。第四章提出了SIP多功能服務(wù)器設(shè)計(jì)的一些設(shè)想，包括其原理和結(jié)構(gòu)。第五章做了總結(jié)和展望。


【關(guān)鍵詞】視頻會(huì)議 可視電話 SIP VOIP H.323 RTP 編解碼
MMX指令



Abstract
With the development of technology in the network and multimedia area, the business of multimedia communication, especially the VOIP technology, has become a leading element in Internet applications. VOIP is the abbreviation of Voice communication Over IP net. It refers to not merely the IP Phone, but also a comprehensive application platform that provides various multimedia operations including video exchange.
Most VOIP systems are based on SIP or H.323 call control protocols. The Session Initiation Protocol(SIP) advanced by IETF has its distinct advantages: it is very concise in the structure, easy to be extended and more suitable to access the Internet. It can control the media gate way and thus control the PC call streaming in a multi-domain network effectively. Under the circumstance that Softswitch is to become the next generation technology of network switch, SIP is considered as the kernel protocol in access layer of the Soft switch technology, and it has been successfully applied to several representative communication systems due to the interest of lots of famous telecommunication companies.
From this point, we have carried out some research work in the construction of SIP based network on Windows platform. This network includes the SIP terminal and server. And our research work includes SIP stack, video and audio codecs and network transmission. This paper also provides some background knowledge about SIP and Video Conference, such as the SIP framework, the history of VOIP and Video Conference, etc.
This paper emphasizes on the implementation of SIP terminal on the Windows platform, including the realization of SIP stack, the capture and compression of video and audio steams, RTP transmission of stream data, the working thread of SIP terminal and the optimization of video codecs. This paper also introduces the structure of standard Video Conference, demonstrates the importance of SIP in the Softswitch network and makes comparison between SIP and the H.323 standard. In the first chapter the history and framework of Video Conference is introduced, and then the author’s research work is also introduced. In the second chapter the author firstly introduces the structure and network model of SIP, then compares SIP with the H.323 standard, and demonstrates the importance of SIP according to the Softswitch network. In the third chapter, the author discusses the realization of SIP terminal in detail, including the implementation of all modules. The author brings out some opinions about the multi-services SIP server in the forth chapter, including its theory and structure. The fifth chapter is about some conclusions and tasks in the future.


[keywords] video conference video phone SIP VOIP H.323 RTP CODEC
MMX instruciton






目 錄
摘 要 I
ABSTRACT II
目 錄 IV
第1章 概述 1
§1.1 視頻會(huì)議系統(tǒng)簡(jiǎn)介 1
§1.1.1 視頻會(huì)議和VOIP的發(fā)展歷史 1
§1.1.2 視頻會(huì)議和VOIP的系統(tǒng)架構(gòu) 3
§1.2 研究工作的簡(jiǎn)要說(shuō)明 7
第2章 SIP協(xié)議與SIP網(wǎng)絡(luò)構(gòu)架 7
§2.1 SIP多媒體通信協(xié)議簡(jiǎn)介 7
§2.1.1 SIP會(huì)話流程和SIP消息的描述 8
§2.1.2 會(huì)議參數(shù)的協(xié)商 13
§2.1.3 SIP中的事務(wù)和對(duì)話 15
§2.1.4 UA的工作機(jī)制 17
§2.1.5 SIP注冊(cè)機(jī)制 19
§2.2 SIP網(wǎng)絡(luò)的構(gòu)架 20
§2.2.1 SIP組網(wǎng)模型 20
§2.2.2 SIP代理服務(wù)器 22
§2.3 SIP與H.323的比較 23
§2.4 SIP與軟交換網(wǎng)絡(luò)體系 27
§2.4.1 軟交換網(wǎng)絡(luò)體系結(jié)構(gòu) 27
§2.4.2 軟交換網(wǎng)絡(luò)中的SIP 30
第3章 WINDOWS平臺(tái)SIP終端的設(shè)計(jì) 32
§3.1 終端方案概述 32
§3.2 SIP終端的運(yùn)作模式 37
§3.2.1 程序初始化 38
§3.2.2 SIP會(huì)議的發(fā)起（加入） 47
§3.2.3 媒體流通信 51
§3.2.4 結(jié)束會(huì)議 58
§3.2.5 斷線監(jiān)測(cè)功能 58
§3.3 SIP協(xié)議棧 59
§3.3.1 OSIP核心協(xié)議棧 59
§3.3.1 UA外圍框架結(jié)構(gòu) 62
§3.4 視頻編解碼器的優(yōu)化 67
§3.4.1 優(yōu)化的策略 67
§3.4.2 編解碼器優(yōu)化過(guò)程 68
§3.5 VIDEXPRESS的測(cè)試結(jié)果 73
第4章 SIP服務(wù)器的設(shè)計(jì)方案 74
§4.1 多用途SIP服務(wù)器概述 74
§4.2 多用途SIP服務(wù)器實(shí)現(xiàn)方案 75
§4.2.1 服務(wù)器網(wǎng)內(nèi)功能模塊 76
§4.2.2 服務(wù)器跨網(wǎng)絡(luò)功能模塊 77
第5章 總結(jié)與展望 77
結(jié) 束 語(yǔ) 79
參 考 文 獻(xiàn) 80
附 錄 83
致 謝 87



參 考 文 獻(xiàn)
[1] 浙江大學(xué)碩士學(xué)位論文 《基于IP的可視電話中H.263+編碼器的實(shí)現(xiàn)及其優(yōu)化》 楊俊智 2003年2月
[2] VoIP技術(shù)及其在寬帶IP網(wǎng)的應(yīng)用 占億民，林寶成 有線電視技術(shù) 2002，9(15)