Methods for allocating transmission bandwidths of a network

Methods for allocating transmission bandwidths of a network are provided. The allocation ratio of anticipation bandwidths is adjusted according to the loading of the network to calculate the requested bandwidths, thereby effectively reducing an average delay and enhancing utility rate of the network. Further, left bandwidth of the network is allocated based on maximum used bandwidth and bandwidth compensation of each terminal during transmission cycle, to allocate excess allocated bandwidth for each terminal; therefore, the transmission bandwidth allocation is with higher justice, and the jitter for delay is reduced. Furthermore, upstream order of each terminal is transferred based on its requested bandwidth, thereby effectively reducing average delay.