Performance evaluation of efficient multipath crossbars

This paper presents a comprehensive analysis of high-performance crossbars where crossbars can be asymmetrical in size, buffered at all crosspoints, and capable of multipath routing. A crossbar, as a building block of switching networks, with the mentioned features in its structure can demonstrate fault-tolerant property. This property is a major factor for crossbars to play the role of high-performance entity in modern computer and communication systems. A generic condition of n × k crossbar with n inputs (rows), k columns, and n outputs (rows) under which a crossbar becomes multipath is examined. In a multipath crossbar a packet can be routed through k different paths to an output. The multipath feature ensures the property of fault-tolerance and provides a faster congestion resolution especially under multicast traffic. The paper describes a two-dimensional Markov chain associated with the queueing model, and presents the performance evaluation of crossbars.