System for determining direct and indirect user access privilege

System for determining successful reception of a message

System for dispensing gift certificates

System for displaying the subscription state of a pay broadcasti

System for distributing digital information

System for diversifying information in a network for distributin

System for embedding authentication information into an image an

System for enabling information marketplace

System for enabling lazy-revocation through recursive key...

System for enciphering or deciphering data

System for encoding and decoding data in machine readable graphi

System for encoding data in machine readable graphic form

System for encoding data in machine readable graphic form

System for encoding data presented with a first coding device an

System for encoding encryption/decryption information into IFF c

System for encoding personalized identification for storage on m

System for encrypted file storage optimization via...

System for encrypted information transmission

System for encrypting broadcast programs in the presence of comp

System for encrypting broadcast programs in the presence of...