To provide a system which allows large volumes of data to be exchanged
efficiently through network connections using portable terminals. An
example data communications system includes a data terminal which stores
certain data; and an operation terminal which controls access rights to
the data stored in the data terminal, in which the operation terminal
grants another operation terminal access rights to desired data. The data
terminal returns the data according to an access request made based on
the access rights. On the other hand, the operation terminal passes the
acquired access rights to the data terminal, which then accesses the data
terminal via a high-speed, stable, wired network and acquires the desired
data, based on the access rights.