Abstract: A data processing system, comprises a first processing resource which is coupled to a communications network. A second processing resource is coupled to the first processing resource. The first and second processing resources are complementarily configured to establish a communications relationship between them for restricting the second processing resource to executing instructions which only perform allowable operations. The data processing system inhibits compromise of the second processing resource.

Abstract: In a system of multiple radiotelephones, such as mobile telephones, wherein each of the telephones is operative with a paging channel by which a calling number is applied to the telephones enabling the respective telephones to respond to their respective channels, the paging channel is utilized for activating individual ones of the telephones. A set of calling numbers is reserved and not employed for calling numbers, but is stored within a memory of each of the telephones. The reserved calling numbers serve as a glossary for encoding words of a command message to be transmitted via the paging channel, and also enable a decoding at each telephone of the encoded message. The command message supplies a designated calling number to a specified one of the mobile telephones, the specified telephone being identified by its electronic serial number.