A robust mechanism for congestion control: INC*

Abstract

Several techniques to prevent congestion in multiprocessor interconnection networks have been recently proposed. Unfortunately, they either suffer from a lack of robustness or detect congestion relying on global information that wastes a lot of transmission resources. This paper presents a new mechanism that uses only local information to avoid network saturation in wormhole networks. It is robust and works properly in different conditions. It first applies preventive measures of different intensity depending on the estimated traffic level; and if necessary, it uses message throttling during predefined time intervals that are extended if congestion is repeatedly detected. Evaluation results for different network loads and topologies show that the proposed mechanism avoids network performance degradation. Most important, without introducing any penalty for low and medium network loads. © Springer - Verlag 2003.