OSMOSIS:
Scalable Real-Time Media Streaming in Ad-Hoc Overlay Networks

Azer Bestavros
Boston University
Computer Science Department


Abstract:

Ad-hoc overlay networks are increasingly used for sharing static bulk
content but their promise for scaling the delivery of on-demand,
real-time content is yet to be tapped. In this talk, we show that
overlay networks could be used efficiently to distribute popular
real-time streaming media on-demand to a large number of clients. We
propose and evaluate OSMOSIS a cache-and-relay end-system multicast
approach, whereby a client joining a multicast session caches the
stream, and if needed, relays that stream to neighboring clients which
may join the multicast session at some later time. OSMOSIS is fully
distributed, scalable, and efficient in terms of network link costs. We
present analytical and empirical results of our evaluation of OSMOSIS.
Our analysis establishes OSMOSIS scalability characteristics under a
variety of assumptions. Our simulations are over large, synthetic random
networks, power-law degree networks, and small-world networks, all of
which could well be representative of ad-hoc overlay topologies, as well
as over large real router-level Internet maps.


Short Biography:

Azer Bestavros obtained his SM in 1988 and his PhD in 1992, both in
Computer Science from Harvard University. He is currently Professor and
Chairman of Computer Science at Boston University.

Professor Bestavros' research interests are in the general areas of
networking and real-time systems. Some of his seminal works include his
generalization of the classical rate-monotonic analysis to accommodate
probabilistic guarantees, his pioneering of the push model for Internet
content distribution adopted years later by CDNs, his characterization
of Web traffic self-similarity and reference locality, his development
of various caching and streaming media delivery protocols, and his
development of efficient techniques for inference of network caricatures
using real-time end-to-end measurement.

Professor Bestavros has an extensive list of publications. In 2000,
WebBib ranked this list as the most referenced body of Web-related
research by a single author. As of July 2004, with over 2,000 citations,
CiteSeer ranks this body of work in the top 500 (5%) of the most cited
in all of Computer Science at all times.

Professor Bestavros received distinguished service awards from both the
IEEE and the ACM. He served as chair, officer, or PC member of most
major conferences in real-time and networking systems, including ICNP,
Infocom, Sigmetrics, Sigmod, RTSS, RTAS, and ICDE. His research has been
funded by grants totaling over $12M from various government agencies and
industrial labs.