Congestion Control Through Input Rate Regulation

Abstract

Traditional packet switching networks have typically employed window-based congestion control schemes in order to regulate traffic flow. In broadband networks, the high speed of the communication links and the varied nature of the carried traffic make such schemes inappropriate. Therefore, simpler and more efficient schemes have to be proposed to fully exploit the large available bandwidth. These schemes usually operate through input rate regulation, typically, they force the information sources to limit their average input rate below some predefined rate while still allowing for a certain degree of burstiness. This ensures that no source will exceed for an extensive period of time the rate provided by the network during the call-setup procedure. The “leaky bucket” scheme is an example of an input rate regulation. In this paper, input rate regulation schemes are extensively studied from the viewpoint of smoothing and regulating effects of the incoming traffic. The smoothing effect is characterized by the variance of the interdeparture time of the packet departure process from the input rate regulation mechanism. Under the assumption of Poisson arrivals the characteristics of this departure process are explicitly derived in terms of scheme’s parameters and the tradeoff between the smoothness of the departure process and packets waiting time is studied. We present results for both finite and infinite buffer pool sizes. © 1993 IEEE