BODHI - A HIGHLY MODULAR TERABIT ATM SWITCH FABRIC ARCHITECTURE

In this paper, we propose a high performance highly modular ATM switch architecture known as Bodhi which is suitable for small, large, and v ery large size ATM switch implementations. Its basic configuration con sists of two stages: an input stage and an output stage. The input sta ge consists of input group modules (IGMs) and output stage output grou p modules (OGMs). Each IGM-OGM pair is connected by multiple paths whi ch carry cells from IGMs to OGMs, Excess cells at the IGMs are recycle d to minimize the cell loss probability. Another module called recircu lation module is used to couple several IGMs together to create additi onal routes For recirculating cells which gives this architecture robu stness against nonuniform and directed traffic. Multicasting has been implemented by integrating copying and broadcasting techniques, and us ing some novel techniques to minimize the switch complexity. A hared b uffer architecture is employed for OGMs such that it implements multip le priorities dynamically in a weighted manner, requires no speedup, a nd, can function in standalone mode as small su itches. The performanc e of Bodhi has been evaluated by computer simulation to select design parameters for a Ik x Ik (k = 1024) switch Fabric. It allows growabili ty from 2.4 gigabit to 150 gigabit switch, and, expandability to 100() Terrabit switch with the complexity increasing approximately linearl y with sine. Based on the study presented in this paper, it is seen th at the Bodhi architecture offers a high degree of modularity, weighted dynamic priority control, robustness against nonuniform traffic condi tions. low complexity, low latency, and, supports multicasting efficie ntly and without any limitation. Bodhi, therefore, has high potential for application In high speed broadband networks.