Buffer management for lossless service in shared buffer switches

Fair scheduling and buffer management are two typical approaches to provide differentiated service. Fair scheduling algorithms usually need to keep a separate queue and maintain associated state variables for each incoming flow, which make them difficult to operate and scale. On the contrary, buffer management (in conjunction with FIFO scheduling) needs only a constant amount of state information and processing, and can be efficiently implemented. In this paper, we consider using buffer management to provide lossless service for guaranteed performance flows in shared buffer switches. We study the buffer size requirement and buffer allocation strategies by starting with the single output switch and then extending the analytical results to the general multiple output switch. We present a universally applicable buffer allocation method for assuring lossless service, and validate the correctness of the theoretical results through simulations.