In a server system having a predetermined total bandwidth providing data files to a plurality of clients in response to requests received from the clients, a method for providing admission control comprises the steps of allocating a plurality of channel partitions to a plurality of channel groups such that each channel group includes one or more of the channel partitions. The system then obtains a channel group number based on the length of the data file requested by one of the clients and transmits the requested data file when a channel group corresponding to the obtained channel group number contains a vacant channel partition.