输入缓冲结构ATM交换网络的窗口接入机理研究

Researches on Window Access Schemes for Input-Buffered ATM Switching Fabrics

本文研究了输入缓冲结构ATM交换网络的窗口接入机理．首先分析了一种传统的相关窗口接入（DWA）机理的最大吞吐率性能，然后，提出了一种独立的窗口接入（IWA）机理，IWA能彻底消除采用传统的DWA机理时在输入缓冲器窗口中存在的队头阻塞现象借助于概率母函数的方法分析了采用该IWA机理的输入缓冲ATM交换网络的时延和吞吐率性能，给出了求解平均信元时延和最大吞吐率的封闭显式．分析表明，IWA机理的性能比传统的DWA机理有较大改善，尤其是在窗口尺寸较小的时候计算机模拟结果验证了理论计算的精确性．

In this paper, the window access schemes for input-buffered ATM switching fabrics are studied. The maximum switch throughput with a haditional Dependent Window Access (DWA) scheme is analyzed;An Independent Window Access (IWA) scheme is proposed, and the performances of an input-buffered ATM switching fabric with the IWA scheme, including the average cell delay and the maximum throughput are analyzed by means of a probability generating functions approach. The analytical results show that the IWA scheme makes the switching fabric have better performances than the DWA scheme, and improvements of the performance are more significant for smaller Window size. Finally, the accuracy of the calculated results is verified by computer simulations.