Fuzzy-based dynamic bandwidth allocation for heterogeneous sources in ATM networks

Abstract

Abstract Asynchronous Transfer Mode (ATM)-based Broadband Integrated Services Digital Network (B-ISDN) is to support multiple classes of traffic with widely different characteristics and Quality of Service (QoS) requirements. A major challenge in this network is to guarantee the promised QoS for the admitted users, while maximizing the resource allocation through dynamic resource sharing. In the case of multimedia call, each of the substreams has its own distinct QoS requirements concerning Cell Loss Ratio (CLR), Cell Transfer Delay (CTD) and Cell Delay Variation (CDV). The ATM network attempts to deliver the required QoS by allocating appropriate resources (e.g. bandwidth, buffers), and bandwidth allocation is a key in achieving this. Dynamic bandwidth allocation polices reported so far in the literature deal with homogeneous sources only. They do not consider QoS parameters and lead to unequal queue growth. In this work, we present and analyze Fuzzy Logic (FL)-based dynamic bandwidth allocation algorithm for heterogeneous sources with multiple QoS (CLR, CTD, CDV, and the arrival rate) requirements. Here, each substream can declare a range of acceptable QoS levels (e.g. High, Medium, and Low). As QoS demand varies, the proposed algorithm allocates the best possible bandwidth to each of the substreams. This maximizes the utilization and fair distribution of resources. We validate the proposed allocation method in a variety of scenarios, and show that the required QoS can be obtained by appropriately tuning the Fuzzy Logic Controller (FLC).