一种新的容错ATM交换机结构的冗余路径分析

The Redundant Path Analysis of A Kind of New Fault-Tolerant ATM Switch

异步传输模式 ATM是国际电信联盟建议用于宽带综合业务数字网 (B- ISDN)的传输模式 .容错是提高网络可靠性的主要方法 .该文讨论了一种新的容错 ATM交换机结构 .该结构以 Banyan交换机结构为基础 ,通过增加子交换单元和扩展链路来增加冗余路径的数目 ,该结构可以容错多个故障 ,并且冗余路径的数目随着交换机级数的增加而指数增长 .同现有文献中其它容错 ATM交换机对比分析可以看出 ,在具有相近的交换元素个数的前提下 ,建议的交换机提供了更高的容错能力 .

We discuss a kind of new fault-tolerant ATM switches based on the Lo's work. This kind of switches is based on Banyan network and increases the redundant paths by subswitches and extended links. This switch is an N×N network with N input ports and N output ports. The network is constructed by adding subswitches between switching stages of the network. Subswitches are added between base switches. Except those in the stages connected with output ports, each base switch has a chain-in link and chain-out link. Similarly each subswitch has a chain-in link and chain-out link And each base switch has an extra link to the subswitch. These construct one kind of multistage interconnection network. We analyze the total number of switching elements and total number of redundant paths of the proposed network. By the analysis we can draw the conclusion that this architecture can tolerate multiple faults and the number of redundant paths increases exponentially as the size of the switch stages increases. Compared with the other architectures with similar number of switch elements found in the literature, the proposed switch is much more fault-tolerant.