Convergence of REM flow control at a single link

Various TCP congestion control schemes can be interpreted as approximately carrying out a certain basic algorithm to maximize aggregate source utility , different schemes corresponding to different choices of utility functions . The basic algorithm consists of a link algorithm that updates a congestio n measure based on its traffic load, and a source algorithm that adapts the source rate to congestion in its path. Though convergent, this algorithm c an lead to large equilibrium backlogs. This problem can be eliminated by mo difying the basic algorithm to include backlog in the update of the congest ion measure. This letter proves that the modified algorithm converges when the network can be modeled as a single bottleneck link. Moreover, in equili brium, the source rates are matched to link capacity while the buffer is cl eared.