To allow only the person in question to use the contents of a cache, when browsing information via a network and caching the information into a terminal.

A proxy server 30 is configured in a terminal 10. Information to be browsed over the network is encrypted by using a user password, being a part of proxy authentication information and stored into a cache area 41. When using the contents of the cache, the contents are encrypted by using the user password. When the passwords match, that is only the identical user is able to use the contents. The cache area 41 is separated respectively for each user, a plurality of users can use their proper encrypted caches in the same manner. The encrypted caches are managed by the proxy server 30 in the terminal 10, so that the caches are available for use even in an off-line state.