文档介绍：南京邮电大学
硕士学位论文
基于SIP协议的会议电话设计研究
姓名:徐伟
申请学位级别:硕士
专业:信号与信息处理
指导教师:曹雪虹
2011-03
南京邮电大学硕士研究生学位论文摘要
摘要
随着计算机和网络技术的快速发展,多媒体通信逐渐成为人们关注的热点,而网络电
话更是这一系列应用的典型代表。这个终端早已不是传统意义上的电话,而是一个可以为
广大用户提供各种多媒体业务的综合应用平台。目前网络实时通信系统采用的信令主要有
协议和 SIP 协议两大主流标准,虽然的发展比较成熟,但 SIP 凭借其具有相对
低成本、简单性、灵活性和易扩展性等特点而成为 3G 网络中的一种核心协议,并且也将在
NGN 中扮演越来越重要的角色,因而大有取代之势。
本文主要研究基于 SIP 网络的会议电话系统,首先讨论 SIP 信令控制协议和其多媒体
技术等关键环节,然后详细叙述了该电话终端的信令控制、音视频等关键模块的实现思想
以及具体流程,并在各模块的基础上给出了基于 SIP 协议的整个电话终端的实现方案。并
且,为了满足多方会议功能,本文分别给出基于该协议典型的分布式和集中式会议模型,
通过理论分析提出了既有利于会议的集中控制,又能减轻会议创建者发送数据负担的两级
集中式会议模型。该模型通过把会议参与者分为双向交互和单向旁听两类,并按特定规则
将其划归为模型两级,达到了减轻创建者数据发送负担的效果,仿真实验验证了该会议系
统模型的合理性。

关键词:会议电话两级集中式 SIP SDP QOS

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南京邮电大学硕士研究生学位论文 Abstract
ABSTRACT
With the rapid development of puter work technology, there has an
increasing focus on the munication while the VoIP is the typical representative
of this series. This terminal is no longer the phone in the traditional sense, but an application
platform which can provide customers a variety of multimedia services. Currently, and
SIP are two major signaling protocols standards in the real-munication system.
Although is a more mature technology, but SIP will replace it for the sake of its features
such as low cost, simplicity, flexibility and ease of scalability. Therefore, it will e the core
protocol in works and play an increasingly important role in NGN.
This paper studies the SIP based conference phone system. Firstly, we discuss the key
module such as the signaling control protocol and the multimedia technology, and then elaborate
on the implement ideas and specific processes of these modules. After that, the realization of this
terminal program is given by the integration of each module. In addition, in order to meet the
multi-party conferencing, this paper gives the distributed and centralized conference models, and
proposes the two-tier centralized conference model which not only