Abstract: The address space of a data storage device is arbitrarily divided into a plurality of data-segments and a different data scrambling algorithm is assigned to each of the data-segments. A programmable address scrambling device is interposed between the address port of the data storing device and a system address bus. An appropriate one of many possible scrambling keys must be supplied to the programmable address scrambling device for each of the data-segments in order to retrieve a desired dataword within each of the data-segments.

Abstract: A system for controlling power at a remote site includes a two channel modem having a first channel dedicated for transmitting power controlling messages to power control modules and a second channel dedicated to transmitting data messages to computerized equipment. The power control modules include a master control module which is plugged into a power line extending through the remote site and one or more slave modules also coupled to the remote site power line for receiving therethrough power control signals transmitted by the master control unit. A user located at a site distant from the remote site may turn power on, off or dim the power to any of a plurality of appliances which are coupled to the remote power line by way of slave power control units.