A scalable consolidation algorithm for point-to-multipoint ABR flow control in ATM networks

Abstract

The key issue at a branch-point switch for point-to-multipoint available bit rate (ABR) flow control is how to consolidate backward resource management (BRM) cells returning from each branch in order to avoid the implosion of BRM cells. However, consolidating the BRM cells at a branch point can cause consolidation noise, delay, and loss. We first investigate the problems of the existing consolidation algorithms, and then propose some solutions for resolving those problems. By combining these solutions, we also propose a new efficient and scalable consolidation algorithm. In the proposed algorithm, each branch point stores the feedback information on a per-branch basis for each virtual connection and passes BRM cells returning from the farthest destination only. Simulation results show that the proposed algorithm can provide a higher efficiency and an excellent scalability, compared with the existing algorithms.