Abstract: A system and method for cryptographic communication among multiple users and a central service provider using in situ generated cryptographic keys. Each user communicates with the central service provider preferably using a user communication interface that includes an in situ key generator, which, after initialization with the user's own individual seed value, generates a unique cryptographic key. By distributing different user individual seeds unique to each user, each user's in situ key generator generates a unique set of keys. The central service provider also possesses an in situ key generator, and also preferably possesses a copy of all the individual seeds assigned to authorized users. The central service provider preferably communicates in a secure encrypted fashion with each user using cryptographic keys generated from that user's individual seed.

Abstract: An apparatus and method for generating pseudo-random cryptographic keys in a cryptographic communications system, whereby, given a common set of initializing configuration data, the pseudo-random cryptographic keys can be duplicatively generated by various independent pseudo-random key generators of the cryptographic communications system. In accordance with the preferred embodiment of the present invention, users of the communications system can each possess an independent pseudo-random key generator to securely communicate with other users also holding independent pseudo-random key generator that share the same initialization configuration data, no matter where the other users are located or whether the users are connected via wire or wireless communication network. The present invention facilitates secure communication without the need to transport decryption keys in advanced, thereby reducing the risk of the secure communication becoming compromised via interception of decryption keys.