Dynamic bandwidth allocating method and device with hardware reduced and bandwidth usability improved

A method in a bandwidth allocating device for allocating, when transmitting a packet from a plurality of subscriber units 0 to (N−1) to a central office device, bandwidths of a plurality of communication channels ch0 to ch(N−1) available for transmission of information to the plurality of subscriber units 0 to (N−1), where N is a natural number, so that,

• when bandwidths requested by the subscriber units 0 to (N−1) or index information allowing calculation of bandwidths requested by the subscriber units 0 to (N−1) is inputted to the bandwidth allocating device,
• a subscriber unit A of the plurality of subscriber units 0 to (N−1) uses at least bandwidths of the communication channels chA and ch(A−1), where A is a natural number less than N,
• that the subscriber unit 0 uses at least bandwidths of the communication channels ch0 and ch(N−1),
• that the subscriber units A and (A−1) share at least bandwidths of the communication channel ch(A−1), and
• that the subscriber units (N−1) and 0 share at least bandwidths of the communication channel ch0,
• where among the plurality of subscriber units 0 to (N−1), a subscriber unit to be allocated to a bandwidth is defined as a subscriber unit K, where K is an integer from 0 to (N−1), inclusive,
• said method comprising the steps of:
• finding a free bandwidth in the communication channel ch(K−1) not used by the subscriber unit (K−1);
• allocating a bandwidth requested by the subscriber unit K to the found free bandwidth in the communication channel ch(K−1);
• finding a free bandwidth in a communication channel chK on the basis of a residual bandwidth requested by the subscriber unit K not allocated to the bandwidth in the communication channel ch(K−1) ;
• and
• allocating the residual bandwidth requested by the subscriber unit K to the found free bandwidth in the communication channel chK,
• said steps of finding the free bandwidth not used in the communication channel ch(K−1), allocating the bandwidth requested by the subscriber unit K to the free bandwidth in the communication channel ch(K−1), finding the free bandwidth in the communication channel chK, and allocating the residual bandwidth requested by the subscriber unit K to the free bandwidth in the communication channel chK being performed for each of the subscriber units 0 to (K−1) and (K+1) to (N−1).