EPFTS中基于时槽加权的公平调度算法

Timeslot Weighted Fair Scheduling in EPFTS

基于EPFTS(ethernet-likephysicalframetimeslotswitching)交换技术,提出了一种新型调度算法TWFS(timeslotweightedfairscheduling),可实现于EPFTS(ethernet-likephysicalframetimeslotswitching)交换节点,满足SUPANET(singlephysicallayeruser-dataplatformarchitecturenetwork)网络中具备QoS(qualityofservice)保障能力的快速数据转发的需要.通过分析两类典型的调度机制iSlip(iterationround-robinmatchwithslip)和BvN-switch(Birkhoff-vonneumannswitch)的优缺点,TWFS利用类似iSlip的迭代机制,以交换节点输入输出端口对上预定的时槽总数作为数据转发的度量权值(优先权),克服了BvN-switch对负载变化反应慢的缺点,同时又使算法时间复杂度保持在与iSlip相同的级别O(log2N).仿真实验结果表明,TWFS算法在算法有效性、公平性和实现复杂度之间取得了很好的平衡,因而特别适合于SUPAENT中的EPFTS高速交换节点.

Based on the technology of EPFTS （ethernet-like physical frame timeslot switching）, this paper introduces a new scheduling algorithm call TWFS （timeslot weighted fair scheduling） which could be implemented in EPFTS nodes to fit the requirement of fast data switching and QoS （quality of service） guarantee in SUPANET （single physical layer user-data platform architecture network）. By analyzing merits and shortcomings of the typical scheduling techniques such as iSlip （iteration round-robin match with slip） and BvN-switch （Birkhoff-von neumann switch）, TWFS utilizes the same iteration mechanism as iSlip and takes the total reserved timeslots of an I/O port pair as the weight （priority） for data switching, thus overcomes the shortcoming of the slow response to traffic fluctuation of BvN-switch, while keeping the same calculation complexity in iteration to O（log2N） as with iSlip. Simulation results have shown that TWFS can made an optimal balance among effectiveness, fairness, and complexity and is most suitable for future high-speed EPFTS nodes in SUPANET.