Patent ID: 7996870

Claim:
A node apparatus in a peer-to-peer (P2P) type data distribution system having a plurality of node apparatuses connected to each other via a network, in which a plurality of contents data and a plurality of divisional contents data are dispersed and stored in the plurality of node apparatuses, the divisional contents data being acquired by dividing the contents data, the divisional contents data being delivered to one of the node apparatuses from another node apparatus in the data distribution system, the node apparatus comprising: a divisional contents data acquisition unit for acquiring the divisional contents data used in an audio data and video data reproduction process that is performed at an n-time speed, wherein n>1, and n=1 is single-speed, in response to performing the reproduction process at the n-time speed using the divisional contents data; a confirmation information acquiring unit for acquiring confirmation information through the network, the confirmation information corresponding to the acquired divisional contents data and the confirmation information used for protecting the acquired divisional contents data against alteration; a certification unit for carrying out a certification process to certify the acquired divisional contents data based on the acquired divisional contents data and the acquired confirmation information using the acquired confirmation information; and a processing unit for carrying out the reproduction process at the n-time speed using the acquired divisional contents data in response to certifying the divisional contents data by the certification unit.