Patent ID: 8589679

Claim:
An identifier-based signcryption method using bilinear maps comprising: a first party associated with a first identifier string ID A signcrypting data m intended for a second party associated with a second identifier string ID B , the first and second parties being respectively associated with first and second trusted authorities that have different respective public keys and different respective private keys s 1 and s 2 ; with a programmed computing entity in communication with a computer network, the first party receives from the first trusted authority a private-key element S A based on the first identifier string ID A and the first trusted party's private key s 1 , and with the programmed computing entity in communication with the computer network, the first party signcrypts the data m using a hash function that accepts as input at least the public keys of the first and second trusted authorities, signcrypting the data m further using said first party's own private-key element S A and the second identifier string ID B .