Fault Tolerant Design of Batcher-Banyan Class ATM Switches

Many proposed packet switching systems for high-speed networks have employed the Batcher-Banyan fabric due to its modular structure, self-routing functionality, and distributed con ict-resolving mechanism. In this paper, we present a systematic fault-tolerant design for the Batcher-Banyan class switches. Our rst concern is the development of an on-line error detection mechanism which is the prerequisite of any e ective fault tolerant operation. Based on the technique developed by Davis [9], we propose a general fault-testing technique and verify it for a variety of unique-path self-routing networks. Furthermore, we extend this method to Batcher sorting networks and construct a fault-tolerant Batcher sorter. Lastly, after contemplating on the technique constraints and system performance, we deploy the above techniques into di erent levels of the Batcher-Banyan networks and achieve a fault-tolerant version of the StarBurst switch, a member of the Batcher-Banyan class switches. 1R. Liao is with Newbridge Networks Corp., Kanata, Ont., Canada, K2K 2E6, (e-mail: [email protected]). This work was carried out when he was in University of Toronto. 2A. Leon-Garcia is with Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ont., Canada M5S 1A4, (e-mail: [email protected]).