光纤通道区分服务优先级流量的路径分配方法

A Route Allocation Method for Differential Service Priority Flows in Fibre Channel Networks

针对航空电子光纤通道网络通信任务服务要求的不同,对于硬实时偶发、硬实时周期以及软实时任务区分优先级,发展了一种优先考虑高优先级任务的端到端延迟保证路径分配方法。采用共轭网络演算分析得到流量经过级联后的端到端最坏情况延迟上限,并结合优先级得到流量的路径。共轭网络演算使级联服务曲线的min-plus卷积转化成变换域中的加法,简化了端到端服务曲线的计算。最后通过一个实例进行分析验证,说明采用上述方法得到路径分配方案可以使高优先级任务的延迟上界小于不进行区分服务的延迟上界。

A novel routing strategy is proposed to satisfy the various service demands on hard real-time sporadic occurrence, hard real-time periodicity and soft real-time in Fiber Channel. This routing strategy gives prior guarantee to the end-to-end delay of tasks with higher priority, The conjugate network calculus, transforming the Min-plus convolution of cascade service curve into addition in transform domain, is applied to analyze the delay upper-bound in those worst cases. Thus a simplified method is given to calculate the service curve of multiple nodes. In the end, an example adopting the above approach is given to achieve the path routing scheme. The simulation results indicate that the delay upper-bound of high priority tasks using proposed approach is much lower than that of tasks using no priority classification.