03/04/02
1. Hari Balakrishnan, V. Padmanabhan, S.
Seshan, M. Stemm, R. Katz, “TCP Behavior of a Busy Internet Server: Analysis and
Improvements”.
Technical Report UCB/CSD-97-966, University of California, Berkeley, CA, August
1997.
2. H. Balakrishnan, H. S. Rahul, and S.
Seshan. “An Integrated Congestion
Management Architecture for Internet Hosts”. In Proceedings of ACM SIGCOMM 1999, pages
175--187, Sep 1999.
3. L. Breslau, E. Knightly, S. Shenker, I.
Stoica, and H. Zhang, "Endpoint Admission Control: Architectural Issues and Performance,"
In Proceedings of ACM SIGCOMM 2000,
Stockholm, Sweden, August 2000.
4. Stefan Savage, Neal Cardwell, David
Wetherall, and Tom Anderson, “TCP Congestion Control with a Misbehaving Receiver”,
In ACM Computer Communications Review,
October 1999.
The whole paper group
centered on TCP performance, and discusses ways in which TCP can be changed, tweaked,
or otherwise improved to increase throughput, better control congestion and
recover from loss faster. All these
papers were very well written and contained interesting (if somewhat dated)
material. The papers presented problems
in TCP, discussed their impacts and suggested improvements that would make TCP
perform better in the Internet environment.
The “TCP Behavior of a
Busy Internet Server: Analysis and Improvements” paper analyzes the performance
of a very busy internet server used during the 1996 Atlanta Olympic games. The authors discuss how performance was
impacted by such a heavy amount of dense traffic. They suggest improvements
such as: enhanced loss recovery, integrated congestion control and loss
recovery, applications level multiplexing, persistent connections in HTTP and
TCP-INT implementation.
The second paper – “An
Integrated Congestion Management Architecture for Internet Hosts” – presents a
method of managing network congestion from an end-to-end perspective using a
congestion manager. Their architecture
consists of an (optional) feedback mechanism and a mechanism which maintains
network statistics and coordinates data streams between particular network
nodes. The goal of this congestion
management scheme is to ensure stable congestion control, efficient flow
scheduling, and better overall performance than “best-effort” networks.
The third paper –
“Endpoint Admission Control: Architectural Issues and Performance” – attempts
to address the problem of efficient and timely admission control on a busy
server. It attempts to combine the
benefits of Integrated Services and Differentiated Services architectures while
diminishing the negative aspects of these two approaches. The paper also provides a discussion of
several scheduling mechanism topics (i.e., FIFO vs. Fair Queuing, coexisting
with Best Effort Traffic, Multiple Levels of Service), and some endpoint
probing algorithms (e.g., Acceptance Thresholds, Accuracy, and Thrashing). It also provides opinions and studies to
show what works and what could be improved.
The fourth paper – “TCP
Congestion Control with a Misbehaving Receiver” – is a very good discussion on
some of the more accessible TCP vulnerabilities and suggests relatively simple
methods to plug these holes. This paper
was the most interesting to me personally.
It contains details on three relatively simple “hacks” or “spoofs” an
unprincipled Internet citizen can use in order to gain better bandwidth (at the
expense of other users). The hacks it
discusses are: Ack-Division, Optimistic-Acking and Multiple-acks. The authors explain that each of these
attacks is relatively easy to implement and carry out. The paper shows in great detail the effects
and dangers of these attacks and suggests some very lucid changes to TCP which
could alleviate these problems.