Improvement of resilient packet ring fairness

Resilient packet ring (RPR, IEEE std. 802.17-2004) is a recent networking standard developed by the IEEE LAN/MAN working group. RPR is an insertion buffer, dual ring technology, utilizing a back pressure based fairness algorithm to distribute bandwidth when congestion occurs. In its attempt to control a set of nodes´ sending behavior over a congested link, the RPR fairness algorithm suffers from two severe performance deficiencies. The first concerns how the node closest to a congested link calculates a fair rate estimate, the second deficiency relates to the method used to distribute this fair rate estimate to nodes upstream from the congested node. In this paper, we analyze these deficiencies and propose improvements to resolve them.