光纤通道交换式网络的虚拟通道分配策略

Allocation Scheme of Virtual Channel in Fibre Channel Switched Networks

为了满足光纤通道(Fibre Channel,FC)交换式网络不断增长的带宽需求,光纤通道协议提出了虚拟通道(Virtual Channel,VC)架构,通过逻辑上的通信通道对整网流量进行合理分配.本文将VC机制由"点到点"扩展为"端到端",并结合网络演算(Network Calculus)理论和信誉量漏桶机制,在强实时条件约束下,提出虚拟通道的分配策略,以减小整网业务流量的端到端延迟时间为优化目标,解决了VC架构的三项技术难题:每种VC数目的确定、每个VC的信誉量(Credit)如何保证、以及每条VC的路径选择.计算机仿真结果表明,随着网络负载强度的不断加大,扩展的VC分配策略具有适应能力,增强了在FC交换式网络中应用VC架构的有效性.

To satisfy the increasing bandwidth requirement of Fibre Channel（FC） switched networks,Virtual Channel（VC） architecture was proposed in new version FC protocols,in order to allocate traffic flows by logical communications channels.Under hard real-time constraint,VC has been expanded from ＂point-to-point＂ to ＂end-to-end＂,and this paper proposes the allocation scheme of VC based on Network Calculus and token bucket to reduce the end-to-end delay of traffic flows in whole FC networks.Thus it has been solved the three hard works in FC protocols：how to determine the number of each kind of VC;how to guarantee each VC＇s credit;and how to choose the path of each VC.Computer simulations results show that VC allocation scheme has good flexibility with traffic increasing intensity,thus enhance the availability of VC architecture into FC switched networks.