Development and analysis of ABR congestion control techniques for wide area ATM networks

Future high speed networks are expected to use the Asynchronous Transfer Mode (ATM) in which traffic with a wide variety of traffic characteristics and quality requirements share a common communication network. ATM traffic management becomes very difficult due to the various types of traffic expected on ATM networks; hence, providing the desired Quality of Service (QoS) for these traffic types is much more complex than for the data networks of today. Among those traffic types Available Bit Rate (ABR) traffic is designed for the future data traffic which takes the left-over bandwidth from the network and is not sensitive to delay but sensitive to cell loss. ABR flow control aims at high link utilization, low ABR cell transmission delay, low ABR cell loss ratio, and fair allocation of available bandwidth. The varying length of ABR source feedback delay, unexpected ABR source behavior, and interference among various links in the ABR control will render the achievement of desired control very difficult and challenging. The research here focuses on the design and analysis of end-to-end rate based feedback flow control of the ABR service in wide area ATM networks. The proposed algorithm is Explicit Rate based and utilizes Self-tuning Fuzzy Control technique, Minimum Variance Prediction technique, and Minimum Variance Control technique, which are shown to successfully handle the ABR congestion control problem under a variety of networking environments. The mathematical analysis also shows that global Max-Min fairness can be achieved in any network topology under the proposed schemes. By using both Local Area Network (LAN) and core-edge Wide Area Network (WAN) architectures with various round trip delays, simulations show that the ATM network can approach the desired network behavior very effectively and maintain high network resource utilization and good fairness. Comparisons with other ABR flow control mechanisms are also performed in both LAN and WAN configurations.