Because of the technique progress in computers and the quick development in communication
networks, the optimum design of the link capacity has become a key problem in the computer networks. In
this paper, a method for the optimum design of the computer networks link capacity is proposed, by which
the overall optimum solution can be abtained. The method applies to the link capacity optimumm designs in
centralized networks and distributed networks. For illustration, an example in design is also presented.