Swarthmore College Department of Computer Science

Talk by Janardhan Iyengar, University of Delaware

Research in Internet Transport Protocols
Wednesday, January 23, 2008
4:00 pm in Science Center 240
Reception and refreshments from 3:45-4:00 pm

Abstract

A computer network is made of many communicating components, and the electrical or optical bits of any user communication or file transfer go over many physical network elements. Architecturally, network communication can be broken down into two logical components: (i) hop-by-hop communication, which is communication between neighboring network elements (routers), and (ii) end-to-end communication, which is the (logical) communication between the endpoints (the computers at the ends). Note that any end-to-end communication is necessarily facilitated by one or more hop-by-hop communication pieces.

This talk will focus on end-to-end communication, particularly at the transport layer in the Internet. In this talk, I will discuss recent advances in transport layer research and my work on Concurrent Multipath Transfer (CMT). CMT, a proposed extension to the Stream Control Transmission Protocol (SCTP, a recently developed transport protocol), enables multihomed endhosts (endhosts with multiple points of connectivity to the network) to increase their throughput by distributing load across multiple interfaces. I will present receive buffer blocking, a problem that occurs in end-to-end multipath transfer with a bounded receive buffer. While receive buffer blocking cannot be eliminated, I will show that it can be reduced by choice of retransmission policy---a mechanism available to only the transport layer.