  ABR traffic management for point-to-multipoint connections controls the
source rate to the minimum rate supported by all the branches of the multicast
tree. A number of algorithms have been developed for extending ABR congestion
avoidance algorithms to perform feedback consolidation at the branch points.
This paper discusses various design options and implementation alternatives for
the consolidation algorithms, and proposes a number of new algorithms. The
performance of the proposed algorithms and the previous algorithms is compared
under a variety of conditions. Results indicate that the algorithms we propose
eliminate the consolidation noise (caused if the feedback is returned before
all branches respond), while exhibiting a fast transient response.
