Radio paging unit

Claim 1

A radio paging unit comprising: input means adapted to be operated by a user to input pieces of various setting information; radio reception means for receiving control information and message information transmitted from a radio base station; message storage means for saving received message information from said radio reception means; encryption means for converting the received message information into encrypted message information; display means for visually displaying the received message information and the encrypted message information; password registration means for registering a password in advance which is used to disclose message contents to limited users; password collation means for collating an input password from said input means with the password registered in said password registration means, and control means, wherein said control means is adapted to store encryption control information for designating whether an encryption mode for message contents is designated on the basis of selection by the user or automatic selection, to allow the user to determine through said input means and said display means whether to perform encryption for each of the pieces of received message information when the encryption control information designates selection by the user, to automatically set the encryption mode of performing encryption of all the pieces of received message information when the encryption control information designates automatic selection, to cancel the encryption mode set for the received message information upon reception of a collation result indicating password coincidence from said password collation means, to cause said display means to display the received message information for which the encryption mode is set after the information is converted into encrypted message information by said encryption means, and to cause said display means to display the received message information, without any conversion, for which the encryption mode is not set.