Patent ID: 7895356

Claim:
An Internet Protocol (IP) router including an IP routing table which stores routing information for connecting a plurality of client devices with an original server which is at least an origin of supplying a content and with a plurality of mirror servers into which the content supplied from the original server is copied, and an IP routing function which performs an IP routing of a received packet according to the IP routing table, the IP router comprising: means for ending a connection relating to a packet output from a specific port of a client device and obtaining request information of a content requested by the client device; means for confirming whether the plurality of mirror servers of the original server exists corresponding to the obtained request information; means for selecting, if the plurality of mirror servers exists, an optimum server, from among the mirror servers, for the request information based on information which is to be an index for selecting an optimum server and based on the routing information; means for obtaining the content by connecting with the selected optimum server; means for transferring the obtained content to the client device; means for detecting a change in a network topology based on a change in the IP routing table; means for altering a selection criteria of the optimum server only when the change in the network topology is detected; and means for altering a band setting for each service class according to a traffic change accompanying an alteration of the selection criteria.