Summary: Dynamic Host­Group/Multi­Destination Routing
for Multicast Sessions
Qi He, Mostafa Ammar
qhe, ammar@cc.gatech.edu
Networking & Telecommunications Group
College of Computing, Georgia Institute of Technology
Atlanta, GA 30332
Abstract
Multicast routing research efforts have mostly focused on supporting the host­group model in which multicast packets are
addressed to a host (or multicast) group. Another multicast routing approach uses multi­destination addressing, where
a multicast packet carries a list of the unique (unicast) addresses of all the group members. This form of routing can be
accomplished using limited or no additional state beyond the existing unicast routing tables. It, therefore, scales well
with the number of multicast sessions but does not scale well with the size of the multicast group and, in fact, requires
the size of the multicast group to be below a certain threshold. In this paper, we envision a future scenario in which
both host­group and multi­destination addressing routing approaches coexist within the Internet. We develop a dynamic
routing context for this future scenario wherein a multicast session can adapt among different routing configurations
depending on the number of multicast group members and how this number changes over time. We consider three
routing options: 1) A single multi­destination addressed flow -- suitable for small­group sessions, 2) multiple multi­
destination addressed flows -- suitable for medium­group sessions and 3) a single host­group addressed flow -- suitable
for large­group sessions. For multicast sessions that vary in group membership over time, different routing protocols

Source: Ammar, Mostafa - College of Computing, Georgia Institute of Technology

Collections: Computer Technologies and Information Sciences