Abstract: To deliver real-time multimedia application end-to-end QoS, Differentiated services (DiffServ) has two key components -- packet marking (classification) and service policy. This paper discusses tools to Implementation of end-to-end QoS for real-time multimedia application. It also gives the analysis of key technologies of DiffServ classification and service policy for Quality of Service (QoS). Then the detail approaches and practical steps of Differentiated Service are proposed to provide the end-to-end Quality of Service (QoS) for real-time multimedia application. The approaches are implemented and evaluated using Cisco router and switch architecture. The results show that network resources are better allocated and control for real-time multimedia application. In the end, the drawbacks and future of the Differentiated Service are set forth.

Key words: Diff-Serv, QoS, Service Policy

摘要： 区分服务(Diff-Serv)模型其主要是通过实时多媒体通信数据包进行分类和策略控制来达到调节网络资源的目的，从而实现对实时多媒体服务端到端服务质量QoS。如何对多媒体网络系统中的不同的信息流进行正确的区分服务，然后对不同类别采取不同的服务策略和拥塞管理，从而对网络资源进行有效配置，是实现实时多媒体服务端到端服务质量QoS的关键步骤。文章重点对实时多媒体信息如何进行分类及相应的服务策略和拥塞管理进行对比研究，提出实现端到端QoS服务质量的具体措施和解决方案．并在Cisco思科路由器和交换机建立的DiffServ网络环境中进行验证，试验结果表明，对实时多媒体信息进行合理的分类及采用相应服务策略，能很好的实现实时多媒体信息流端到端的服务质量QoS．最后阐述了DiffServ区分服务存在的问题和未来的发展趋势．

关键词: 区分服务(Diff-Serv), QoS服务质量, 服务策略