Summary: Deploying Safe User­Level Network Services with icTCP
Haryadi S. Gunawi, Andrea C. Arpaci­Dusseau, and Remzi H. Arpaci­Dusseau
Computer Sciences Department
University of Wisconsin, Madison
{haryadi, dusseau, remzi}@cs.wisc.edu
Abstract
We present icTCP, an ``information and control'' TCP implemen­
tation that exposes key pieces of internal TCP state and allows
certain TCP variables to be set in a safe fashion. The primary
benefit of icTCP is that it enables a variety of TCP extensions
to be implemented at user­level while ensuring that extensions
are TCP­friendly. We demonstrate the utility of icTCP through
a collection of case studies. We show that by exposing infor­
mation and safe control of the TCP congestion window, we can
readily implement user­level versions of TCP Vegas, TCP Nice,
and the Congestion Manager; we show how user­level libraries
can safely control the duplicate acknowledgment threshold to
make TCP more robust to packet reordering or more appropri­
ate for wireless LANs; we also show how the retransmission
timeout value can be adjusted dynamically. Finally, we find that

Source: Arpaci-Dusseau, Andrea - Department of Computer Sciences, University of Wisconsin at Madison
Arpaci-Dusseau, Remzi - Department of Computer Sciences, Department of Computer Sciences, University of Wisconsin at Madison

Collections: Computer Technologies and Information Sciences