Patent ID: 7149308

Claim:
A cryptographic communication system comprising: a plurality of user communication interfaces, each of said communication interfaces including: a data transceiver; a string generator; a data processor connected to said string generator; and a memory connected to said string generator, said memory having stored a unique seed value and a common seed value, wherein the data processor processes data received by or to be transmitted by the data transceiver using data string generated by the string generator, wherein the unique seed value for each of said plurality of user communication interfaces are unique to the respective communication interface, and wherein the common seed value stored in the memory of each of said plurality of communication interfaces is common to all of the plurality of communication interfaces, and wherein the string generator generates data string using the unique seed value if the data to be transmitted or received by the data transceiver is unicast data intended to be received by one of said plurality of communication interfaces, and generates data string using the common seed value if the data received is designated as multicast data intended to be received by all of said plurality of communication interfaces; and a master station, said master station including: a second data transceiver; a second string generator; a second data processor connected to said second string generator; and a second memory connected to said second string generator, said second memory having stored each of the unique seed value stored in the plurality of communication interfaces and the common seed value, wherein the second data processor processes data to be transmitted by or received by the second data transceiver using data string generated by the second string generator, and wherein the second string generator generates data string using one or more of the unique seed values if the data to be transmitted by or received by the second data transceiver is intended to be received by select ones of said plurality of communication interfaces, and generates data string using the common seed value if the data to be transmitted is intended to be received by all of the plurality of communication interfaces.