Congestion control for ABR traffic in satellite networks

The ABR service suffers greatly from the long propagation delays typical of satellite networks. It has, in fact, been shown that a long delay, in comb ination with a high bandwidth, can deceive ABR sources and make them believ e that a break has occurred somewhere along the path. ABR sources respond t o breaks by reducing their cell rate, so resource utilization decreases dra stically. The solution to this problem has been to reduce the cell rate onl y when feedback from the network has been missing for a period longer than the round trip delay. However, this delay in reducing the cell rate causes many additional cell losses if a break actually occurs. In this paper, a fr amework is introduced for ABR traffic control in satellite ATM networks. Th e framework is composed of an accurate analytical model for standard ABR tr affic behavior in long propagation delay networks, and new procedures which avoid false decreases in the cell rate. The analytical model is used to fo recast false decreases of the cell rate and trigger the new procedures. Ove rall, the proposed framework avoids a reduction in network utilization with out causing additional losses. (C) 2001 Elsevier Science B.V. All rights re served.