| 摘要 |
<p>A technique for maintaining availability of content for distribution in a P2P system. An information processor (2) is connectable to a communication system (1) containing a plurality of terminal devices (3a, 3b, 3c). The information processor (2) receives content holding terminal information for identifying a terminal device holding a specific item of content, calculates a content holding terminal number corresponding to the number of terminal devices holding the content on the basis of the received content holding terminal information, holds a determination reference serving as a reference for determining whether the content holding terminal number is below a predetermined threshold value, determines on the basis of the content holding terminal number calculated by the terminal number calculator and the determination reference whether the content holding terminal number concerned is below the predetermined threshold value, and transmits an extinction preventing instruction for making the terminal device holding the content concerned execute processing for preventing extinction of the content when determining that the content holding terminal number is below the predetermined threshold value.</p> |
