To provide a high-quality content distribution service to each user terminal, in an environment where a communication band between a content server and a user terminal greatly differs for each user.

A network management/control system retains the line band value of an access line notified from an access server for accommodating the user terminal as a band value that can be utilized by the user terminal. When the content server retaining a plurality of contents edited to a plurality of communication bands receives a content distribution request from the user terminal, the content server inquires from the network management/control system of the band value that the user terminal can utilize, thus selecting and distributing a content suited for the communication band equal to or smaller than the band value, and distributing optimum contents to the user terminal in the content distribution network.