Algorithm-Based Fault Tolerance for FFT Networks

Call packing has been recognized as a routing scheme thatsignificantly reduces the blocking probability of connection requests ina circuit-switched Clos multistage interconnection network. In this briefcontribution, for the first time, we develop general analytical models forthe point-to-point blocking probability of the call-packing scheme appliedto Clos networks. By introducing a new parameter called the degree ofcallpacking, the models can correctly estimate the blocking probability ofboth call-packing and random routing schemes. The models are verifiedby computer simulation for various size networks and traflic conditions. Index TermBlocking probability, call packing, circuit switching,Clas network, multistage interconnection network, path rearrangement,random routing. Manuscript received May 18, 1992 revised September 27, 1992; revisedJanuary 7,1993. This work was supported in part by NSF Grant MIP-9196165and Texas State Government Grant ATP 18-269.Y. Mun was with the Department of Computer Science Engineering. TheUniversity of Texas at Arlington, Arlington, Texas 76019-0015 USA. He isnow with the Department of Computer Science. Soongsil University, Seoul,Korea.H. Y. Youn is with the Department of Computer Science Engineering, TheUniversity of Texas at Arlington, Arlington, Texas 76019-0015 USA; e-mail:[email protected] Log Number 9213781.