Overhead estimation of selected protocols for file transfer

Abstract

In this paper, we derive an analytical model for the estimation of the overhead introduced in a file transfer procedure by three different reliable protocols, namely TCP, SCTP, and Saratoga. The model estimates the introduced overhead down to the IP layer, taking into account uncorrelated packet loss on the channel. The model distinguishes between the overhead on the forward link (server to client), mainly due to packet headers and retransmissions, from the overhead on the return link (client to server), which is mainly due to acknowledgments. By carrying out experimental tests, we show that the model predictions match very well with the trial results. Further, Saratoga shows the lowest overhead costs, especially for the smaller files sizes; nevertheless, on the expense of removing mechanisms like flow control and congestion control.