基于SCTP的满意QoS覆盖多播实现方案的研究

现有的覆盖多播方案皆存在因传输层的单穴技术所导致的固有性能缺陷,为提高覆盖多播的传输性能,提出了相应的解决方案,首先基于传输层多穴技术的高容错性和同时多路径传输能力,采用层次化的设计思想提出了抽象服务接口层、传输服务层和覆盖多播层的多穴覆盖多播网络体系结构,造就了具有QoS保证实时媒体交付的基础环境.其次基于该体系结构设计了满意QoS多播算法,它是该方案的核心,该算法可为服务代理建立满意QoS多播服务树从而实现服务代理间的覆盖流量负荷的平衡提供保障.仿真实验表明该方案可有效地消除现有覆盖多播方案在满意QoS比率、多播树代价、平均链路压力和平均路径长度方面的性能瓶径,可进一步提高现有覆盖多播业务的服务质量.

QoS Satisfied Overlay Multicast Based on SCTP

The existing overlay multicast schemes have a common inherit performance limitation caused by transport layer singlehoming technologies. In order to improve the transfer performance of overlay multicast, a new network architecture of overlay multicast based on high fault tolerance and concurrent multipath transfer of transport layer multihoming was designed, which includes abstract service interface layer, transport service layer and overlay multicast layer. The QoS-satisfied multicast algorithm based on such overlay multicast architecture was presented, which established QoS-satisfied multicast tree and overlay traffic balance among the service brokers. The simulation showed that such new scheme eliminated the performance bottleneck such as QoS-satisfied ratio, multicast tree total cost, average link stress and average path length effectively.