§1.5 VoIP 的服务质量............................................................................................8
§1.5.1 影响语音质量的因素...........................................................................8
§1.5.2 VoIP 的QoS 技术参数.......................................................................10
§1.6 本文的主要研究内容和所做的工作...........................................................12
§1.7 本文的组织结构...........................................................................................13
第二章 播放同步机制与 RTP/RTCP 协议...................................................................14
§2.1 播放同步机制...............................................................................................14
§2.1.1 固定延迟播放策略.............................................................................15
§2.1.2 自适应延迟播放策略.........................................................................16
§2.2 RTP 基本作用...............................................................................................17
§2.3 RTP 分组格式...............................................................................................18
§2.3.1 RTP 端口分配.....................................................................................21
§2.4 混合器和转换器...........................................................................................21
§2.5 RTP 控制协议(RTCP)...................................................................................22
§2.5.1 RTCP 发送者报告(SR)分组...............................................................23
§2.5.2 RTCP 接收者报告(RR)分组...............................................................26
§2.5.3 RTCP 源终端描述(SDES)分组..........................................................27
§2.5.4 BYE 分组............................................................................................27
§2.5.5 应用相关功能分组.............................................................................28
§2.6 RTP/RTCP 协议在应用层保证多媒体信息实时传输................................29
§2.7 RTP/RTCP 协议在实际应用中的一些改进................................................29
§2.8 本章小结.......................................................................................................30
第三章 VoIP 实时语音系统的设计与实现及其应用层 QoS 控制策略.....................31
§3.1 系统概述.........................................................................................................31
§3.2 VOCAL 系统简介..........................................................................................31
§3.3 系统原理.........................................................................................................33
§3.4 系统主要数据结构.........................................................................................34
§3.5 系统结构设计与实现.....................................................................................35
§3.5.1 主线程...................................................................................................36
§3.5.2 发送端线程...........................................................................................37
§3.5.3 接收端线程...........................................................................................38
§3.5.4 流量调节线程.......................................................................................38
§3.5.5 协议栈部分...........................................................................................39
§3.6 系统的应用层 QoS 控制策略........................................................................43
§3.6.1 时延控制策略.......................................................................................43
§3.6.2 抖动控制策略.......................................................................................45
§3.6.3 丢包修复的策略...................................................................................46
§3.7 本章小结.......................................................................................................50
第四章 VoIP 网络层 QoS 保证机制.............................................................................51
§4.1 综合服务/资源预留协议 RSVP..................................................................51
§4.2 DiffServ 差分服务模型介绍........................................................................52
§4.2.1 差分服务中标记策略.........................................................................53
§4.2.2 差分服务中队列管理.........................................................................55