组播技术及其在光层的实现

带宽密集型的多媒体应用对现有网络提出了新的要求,组播技术有助于解决其在网络带宽和服务质量方面的问题,而在光层实现组播具有更简单、高效的特点.然而,光层组播由于光缓存、光分束和光波长变换等光器件的限制,呈现出和IP层组播不同的特点.对IP层和光层组播进行了讨论,分析了光层组播模型,并对稀疏光分束和稀疏波长变换的光网络组播路由提出了重路由到源和重路由到相关节点两种重路由方式.

Multicast Technology and Its Realization at Optical Layer

Since bandwidth-intensive multimedia applications have raised new request on existing networks, multicast technology can contribute to solve the issues of network bandwidth and quality of service, especially, multicast at optical layer is more simple and efficient. However, owing to some limitations on optical buffer, light splitter, and wavelength converter, optical multicast at optical layer offers different characteristics from those at IP layer. Consequently, the IP multicast and optical layer multicast are discussed, the model of optical layer multicast is analyzed, and two reroute approaches for multicast route in an optical network with sparse splitting and sparse wavelength conversion are proposed. Of which, one is reroute-to-source, and the other is reroute-to-relative.