A stateless approach for improving TCP performance using Diffserv

In TCP connections, the loss of some segments has more impact than the loss of others on the performance of the connection. These segments are (i) the connection establishment segments, (ii) the segments sent when the connection has a small window, and (iii) the segments sent after a timeout or a fast retransmit. We call these "vulnerable" segments, or packets. In the two recent papers [9,10], the authors show that by marking these segments with a higher priority and implementing the priority using a diffserv architecture, the performance of the TCP connection considerably improves. The marking proposed in these references requires, however, that network layer elements be aware of transport layer information, i.e. of the state of the TCP connection. The goal of our paper is to show that one can achieve prioritization of sensitive segments without any use of transport layer information, thus simplifying the implementation of diffserv marking of TCP packets.