Abstract: In order to solve the problem of insufficient execution time of the algorithm in the feedback-based two-stage switch architecture, a multichannel-feedback-based two-stage switch architecture called MFTS is proposed in this paper. The status data of the middle-stage buffers can be transmitted to the input port along the two-stage crossbars. The scheduling algorithm of input port can be started in advance based on the processed data. Any input port can obtain the scheduling results of the adjacent input port by the dedicated communication link. Based on such scheduling information and the inherent characteristics of the crossbar connection pattern, the scheduling algorithm is finalized and the final ruling result is used as the final algorithm scheduling result. Compared with the existing solutions, MFTS can increase the scheduling algorithm execution time by 2 times while avoiding packet collision and packet disordering problems, which makes it possible to support larger switching scale and higher port rate.

Key words: packet switching, switch fabric, load balancing, feedback mechanism

摘要： 为解决反馈型两级交换结构中算法可执行时间不足的问题，提出一种多路反馈型两级交换结构MFTS。该结构通过两级crossbar将中间缓存的状态数据反馈到输入端口，输入端口基于处理后的数据提前开始进行算法调度；通过相邻输入端口之间的通信链路使得任一输入端口都能获得邻端口的调度信息，基于该信息和crossbar连接模式的固有特性对调度算法的结果进行终裁，将终裁结果作为最终的算法调度结果。相对于现有方案，MFTS在避免数据包冲突和数据包失序问题的前提下将调度算法可执行时间提高两倍，这使其可支持更大交换规模和更高的端口速率。

关键词: 包交换, 交换结构, 负载平衡, 反馈机制