There is provided semiconductor memory capable of reconfiguring an area to
be given an authentication key and access limitation, and there is
implemented an information distribution system having an advanced
security function using the semiconductor memory.Part of a storage area
in the semiconductor memory stores information about the area to be given
the authentication key and the access limitation. Alternatively, the
authentication key is stored in units of data to be authenticated for
limiting an access to stored information. Information is protected doubly
by storing encrypted information in the area provided with the access
limitation according to the above-mentioned method.