File distribution method and client terminal implementing the same

A client terminal comprising:

• means for constructing a P2P group with other client terminals;
• means for requesting a server for the transfer of information concerning files held within said server;
• means for searching through the client terminals belonging to said P2P group for a client terminal holding a file that is indicated in said information transferred from said server and that is determined as being needed;
• means for acquiring said file from the client terminal found to hold said file as a result of said search;
• and
• means for acquiring said file from said server when no hit is found as a result of said search.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for distributing a file to a plurality of client terminals, said method steps comprising:

• constructing in advance a P2P group that comprises at least some of said plurality of client terminals;
• sending a request from a first client terminal belonging to said P2P group to a server for the transfer of information concerning files held within said server;
• when any file indicated in said information transferred from said server is needed, then searching through the client terminals belonging to said P2P group for a second client terminal holding said file;
• when a hit is found as a result of said search, then sending a request from said first client terminal to said second client terminal for the transfer of said file;
• and
• when no hit is found as a result of said search, then sending a request from said first client terminal to said server for the transfer of said file.