Design and evaluation of feedback consolidation for ABR point-to-multipoint connections in ATM networks

The available bit rate (ABR) service is proposed to transport data traffic in asynchronous transfer mode (ATM) networks. ABR is unique because the net work switches can indicate to the sources the rates at which they should be transmitting, thereby avoiding congestion and efficiently utilizing networ k resources. A number of algorithms have been developed for extending the A BR flow control algorithms for point-to-multipoint connections. In this cas e, feedback consolidation is required at the branch points to avoid overwhe lming the sender with feedback. This paper discusses various design options and implementation alternatives for consolidation algorithms, and proposes a number of novel algorithms. The performance of the proposed algorithms a nd the original algorithms is compared under a variety of conditions. Resul ts indicate that the algorithms we propose eliminate the consolidation nois e (caused if the feedback is returned before all branches respond), while e xhibiting a fast transient response. (C) 1999 Elsevier Science B.V. All rig hts reserved.