The effect of multiplexing HTTP connections over asymmetric high bandwidth-delay product circuits

A. McGregor - M. Pearson - J. Cleary

November 1998

Abstract:

The growth of the Internet is placing strain on the world wide telecommunications infrastructure. In particular it is no longer possible to purchase capacity on terrestrial cables to some parts of the world. To meet the growing traffic needs of the Internet some Network Service Providers are deploying asymmetric satellite connections. These providers must choose an architecture for the international component of the network. Depending on the architecture chosen the traffic on the international circuit might be made up of a large number of independent connections or a smaller number of connections carrying aggregated traffic. The appropriate approach is not immediately apparent because there are opposing performance factors and because the effect of asymmetric delay on TCP performance is not well understood. In this paper we describe a discrete event simulation of the effect of carrying multiplexed HTTP connections over an asymmetric high bandwidth delay circuit. We show that a high degree of multiplexing mitigates against TCP's bandwidth delay product limits but that using a TCP connection per HTTP request causes a significant increase in delay.

TCP/IP performance, satellite, asymmetric delay