Window-time-space flow control (WTFC)

End to end flow control will be essential for data communications in the near future B-ISDN network, because of its heterogeneous structure. The network is considered a black box from the transmitters point of view, and modeled with G/G/I queuing system. The window bounded D/D/1/W model and window-time (WT) plane are defined using the previous result, that with lowering variance and keeping QoS constant, network delay curve approaches the D/D/1 one. On this basis, a new window-time-space flow control (WTFC) is developed, which enables the transmitter to estimate its optimal packet sending rate and window, under condition that total network (path) capacity is known. The total capacity can be signaled from the network or estimated by the transmitter. Simulation measurement results are presented and analyzed.