The One-to-Many TCP Overlay: A Scalable and Reliable Multicast Architecture
We consider reliable multicast in overlay networks where nodes
have finite-size buffers and are subject to failures.
We address issues of end-to-end reliability and throughput
scalability in this framework.
We propose a simple architecture which consists of using distinct
point-to-point TCP connections between adjacent pairs of end-systems,
together with a back-pressure control mechanism
regulating the transfers of adjacent TCP connections,
as well as a back-up buffering system handling node failures.
This architecture, that we call \textit{the One-to-Many TCP Overlay},
is a natural extension of TCP to the one-to-many case, in that
it adapts the rate of the group communication to local congestion
in a decentralized way via the window back-pressure mechanism.
Using theoretical investigations, experimentations in the Internet,
and large network simulations, we show that this architecture
provides end-to-end reliability and can tolerate multiple simultaneous
node failures, provided the backup buffers are sized appropriately.
We also show that under random perturbations caused
by cross traffic described in the paper, the throughput of this
reliable group communication is always larger than a positive constant,
that does not depend on the group size. This scalability result
contrasts with known results about the
non-scalability of IP-supported multicast for reliable group
communication.
Philippe Nain
Last modified: Tue Mar 15 14:46:45 MET 2005