A Flexible Multipoint-to-Point Traffic Control Algorithm for ABR Services in ATM Networks

Traffic control for point-to-multipoint ABR services in ATM networks has been studied extensively, but this is not the case for multipoint-to-point (mp-p) traffic control. No consensus has been reached concerning the issue of fairness of bandwidth allocation among multipoint connections, or between point-to-point and multipoint connections. Existing mp-p traffic control schemes for ABR services either support only a limited set of fairness definitions, or are not effective. In this paper, we define a new type of fairness, and propose a flexible multipoint-to-point traffic control scheme for ABR services. The proposed scheme supports cell merging at both virtual path (VP) and virtual connection (VC) levels, and implements all existing types of fairness currently defined in the literature for mp-p communications. This flexibility allows the network to meet various bandwidth requirements of different application streams. It also permits switch vendors to quickly configure their switches to meet clients' requirements, despite the lack of consensus on the issue of fairness definition. While being flexible, the new algorithm is also fair, fast and robust. Simulation results show that the proposed scheme is fair, and performs as well as, or better than existing mp-p traffic control schemes. It is also easy to incorporate the new algorithm into a multipoint-to-multipoint traffic control scheme such as the framework proposed by Ren, Siu and Suzuki.