Subject: Another PILC paper

From: Reiner Ludwig <[email-masked]>
Date: Mon, 19 Jul 1999 09:28:24 -0700

we have just finished another "PILC paper" you can download from
http://iceberg.cs.berkeley.edu/papers/Ludwig-WINET99/ . The title and
abstract are attached below. I will present the paper at this year's
MOBICOM conference.

///Reiner

Title:
"Optimizing the End-to-End Performance of Reliable Flows over Wireless Links"

Abtract:
Pure end-to-end error recovery fails as a general solution to optimize
throughput when wireless links form parts of the end-to-end path. It
can lead to decreased end-to-end throughput, an unfair load on best-effort
networks, and a waste of valuable radio resources. Link layer
error recovery over wireless links is essential for reliable flows to avoid
these problems. We demonstrate this through an analysis of a large
set of block erasure traces measured in different real-world radio
environments, with both stationary and mobile hosts. Our analysis is
based on a case study of the circuit-switched data service implemented in
GSM. We show that the throughput on this wireless channel can
be increased by using a larger (fixed) frame size for the reliable link
layer protocol. This yields an improvement of up to 25 percent when
the channel quality is good and 18 percent even under poor radio
conditions. Our results suggest that adaptive frame length control could
further increase the channel throughput. Finally, we discuss link and
transport layer error control mechanisms and their interactions with
end-to-end congestion control schemes. For reliable flows, we argue in
favor of highly persistent error recovery and lossless handover
schemes implemented at the link layer.