From: Tom Christiansen (tomchr@ee.washington.edu)
Date: Sun Nov 07 2004 - 17:37:50 PST
This paper presents an analysis of network traffic to/from UW over a 9-day
period. The purpose of this analysis is to gain a detailed understanding of
how content delivery systems are used in practice. From the analysis, it
is concluded that 75 % of HTTP traffic is Peer-to-Peer traffic and that the
average size of P2P objects is three orders of magnitude larger than the
average size of a web object. In addition, it turns out that a few select
P2P objects account for a significant portion of the total requested number
of bytes. Hence, the idea of employing a P2P or content delivery network
cache is investigated. From this investigation (based on an ideal cache) it
is concluded that the peak bandwidth savings which could be achieved by
employing this cache is on the order of 120 Mbit/sec.
It is interesting to note that a large number of the server requests
associated with P2P services such as Kazza result in a "service
unavailable" error. It sounds like the P2P systems were hard pressed
against the bandwidth limit (or limits on available connections) even in
2002. It would be interesting to see a similar analysis performed today
after the legal concerns and intellectual property issues associated with
file sharing have been the focus of media attention for a while.
The paper raises concerns about the scalability of current P2P systems. It
seems fairly evident that the current protocols are hard pressed against
the limits and that a different methodology should be employed in order for
P2P traffic to continue to grow.
The paper is generally well-written, reasonably concise and to the point,
and presents good data. The weak spot is obviously the cache
simulations/analysis which appear to have been thrown in as an aside. The
authors also acknowledges this fact and promise a follow-up article on
caching. Hopefully, the follow-up will include data from a real-world
system rather than an ideal cache (infinite memory).
This archive was generated by hypermail 2.1.6 : Sun Nov 07 2004 - 17:38:09 PST