Subject: 5/3 Design and Evaluations of Multimedia Proxy Caching Mechanisms for the Internet -- Reza Rejaie, AT&T Labs - Research

From: Florissa Colina <[email-masked]>
Date: Tue, 02 May 2000 10:30:00 -0700

Berkeley Multimedia, Graphics and Interfaces Seminar

Design and Evaluations of Multimedia Proxy Caching Mechanisms for the Internet

Wednesday May 3, 2000 
1:10-2:30 p.m. PDT
Fujitsu Seminar Room (405 Soda Hall) 

Reza Rejaie
AT&T Labs - Research 

Most of the existing Internet multimedia streaming applications are based
on the client-server architecture. This architecture has two major
limitations: 1) The quality of delivered streams is limited to the
bottleneck bandwidth between the server and the client. Thus a client with
a high bandwidth local connectivity may receive low quality streams due to
a remote bottleneck. 2) Its scalability is limited, in that it is difficult
to support a large number of concurrent high quality sessions due to
network and server load. Multimedia proxy caching (MCaching) is a natural
extension of the client-server architecture that addresses both limitations
simultaneously. The idea is to cache popular streams with appropriate
quality at a proxy close to interested clients. Thus the proxy can
effectively enhance the delivered quality and improve scalability by
significantly reducing the load on the network and the server. 

In this talk, we address the design and performance evaluations of MCaching
mechanisms. First the design of an efficient MCaching mechanism for
layered-encoded streams is outlined. We observe that in addition to cache
efficiency (measured by hit ratio), MCaching introduces the notion of
``quality'' for delivered streams as a new dimension to Web caching. Thus
performance of MCaching mechanisms should be collectively evaluated along
both dimensions caching efficiency and delivered quality. We identify a
fundamental tradeoff between these two dimensions. Our simulation results
show that our proposed MCaching design can adaptively exploit this tradeoff
to improve overall performance whereas simple extension of current Web
caching schemes can only enhance the performance along one dimension.
---------------

The seminar is broadcast live on the Internet Mbone and as a Real Networks
G2 broadcast.

You can connect to the live RealNetworks broadcast at:

http://media2.bmrc.berkeley.edu/bibs/schedule.cfm 
You'll see a link to cs298-5/real networks/live programs.  

You can also directly put in this url into the Real Player: 
rtsp://media2.bmrc.berkeley.edu/encoder/cs298-5.rm

To do so you will need to have the "Real Player G2" installed, which is
available from:
http://www.real.com/products/player/downloadrealplayer.html

To tune into the Internet MBone broadcast, look for the announcement in
your MBone session directory program ('sdr').  If you are not receiving the
announcement you may be able to receive the session by manually configuring
the client programs ('vic', and 'vat') with the session addresses:

low bit rate
	video: 233.0.25.1/22334
	audio: 233.0.25.2/22446

medium bit rate
	video: 233.0.25.129/22334
	audio: 233.0.25.2/22446

You can get further information about this seminar, and access to replays
of previous seminars at the MIG Seminar web page:

http://bmrc.berkeley.edu/298/index.html

Sponsored by the Berkeley Multimedia Research Center