1. A method for communicating information, in a data communication system, between at least a first correspondent and a second correspondent interconnected through a data communication channel therebetween, said method comprising the steps of: a) selecting a plurality of cryptographic algorithms known to said first correspondent and second correspondent; b) said first correspondent applying each of said selected cryptographic algorithms to the same information in a common message in a predetermined manner for producing for that algorithm a corresponding set of processed information; c) said first correspondent transmitting said sets of processed information to said second correspondent; and d) said second correspondent applying complementary operations of each of said selected cryptographic algorithms in accordance with said predetermined manner to respective ones of said sets of processed information for deriving, from each of said sets of processed information, information related to said common message.