Patent ID: 7836125

Claim:
A method of reproducing updated message data in a content medium player connected to a content server via a communication network, the method comprising: playing back content stored on the content server and/or a recording medium provided to the content medium player along with message data transmitted from the content server, the step of playing including sending a request along with last update time (LUT) information to the content server to transmit updated message data received from another content medium player, wherein the LUT information indicates a time when last updated message data from the another content medium player, received by the first content medium player, was originally received by the content server, and wherein the LUT is measured relative to the playback starting time of the recording medium; and receiving, from the content server, new message data sent from said another content medium player, the new message data being received by the content server after the time when the last updated message data from the second content medium player was originally received by the content server, the step of receiving including receiving new LUT information associated with the received new message data.