Robust congestion control for ATM ABR service with non-responding connections

Abstract

We propose a robust congestion control scheme for the ATM ABR service, which has non-responding connections. The control scheme is robust with respect to both the round trip delay and the loss of control information caused by non-responding connections. It is applied to both the unicast network and the multicast network. There are two typical methods for congestion control in ATM ABR service; congestion indication (CI) method and explicit rate (ER) based method. Out of them, the explicit rate (ER) indication based feedback flow control for the ABR service is more effective, but a little more complex than binary congestion indication (CI) based scheme. In this thesis, we want to structure and develop our ideas on the basis of ER indication scheme. We begin with a simple controller, and then increase the order of controller for more powerful stability margin in the case of losing control information. In addition, most of the proposed congestion control solutions cannot confirm the robust stability with respect to the unknown round trip delay, however we also want to solve such a problem. Finally, we extend the control scheme for non-responding problem in unicast network to the multicast network, which has more complexity. Thus, it is shown that the proposed control scheme guarantees the QoS of the network.