Patent ID: 8086629
Filing Date: 2011-12-27
Classification: G06F,H04L,Y10S

Abstract:
1. A content delivery apparatus constituting a node of a P2P network, the P2P network that: defines, as a downstream node, a sender node for transmitting, to an adjacent node, tag information indicative of locations of holding nodes that hold delivery target contents and information of the holding nodes; defines, as an upstream node, a destination node for receiving the tag information; and gathers the tag information more in the upstream node to increase content-search efficiency or content-delivery efficiency, the content delivery apparatus comprising: a tag information storage means that stores tag information of a delivery target content held in its own node and tag information received from each downstream node adjacent to its own node; a tag information merging means that, when there is a plurality of divided pieces of tag information for divided contents created by dividing the same content or a plurality of divided pieces of tag information for divided contents created by dividing, in contents, a group of a plurality of contents in the tag information stored in the tag information storage means, merges the plurality of divided pieces of tag information into merged tag information, and stores the merged tag information in the tag information storage means and in an internal tag information storage means that internally manages the plurality of merged pieces of tag information; a tag information distributing means that transmits the merged tag information to an upstream node adjacent to its own node; and a content transmitting means that, in response to a download request from an alternative node, uploads the delivery target content held by its own node to the download requesting node, wherein the tag information includes part information which part of an entire content is held, the tag information merging means merges pieces of the part information of the pieces of tag information on the divided contents with each other, and creates the merged tag information by setting the location of the held node as its own node, and the content transmitting means comprises: means for uploading the delivery target content held by its own node to the download requesting node when its own node holds the delivery target content; and means for transmitting, when its own node does not hold the delivery target content and stores a plurality of pieces of tag information on a content that is the same as the delivery target content in the internal tag information storage means, the plurality of pieces of tag information stored in the internal tag information storage means to the download requesting node.