Patent ID: 7634085

Claim:
A computer-implemented method for using identity-based-encryption (IBE) with partial attribute matching to support secure communications, wherein an attribute overlap threshold d with an integer value defines a required degree of attribute matching for successful decryption, comprising: at a sender, running an IBE encryption engine with computing equipment to encrypt plaintext M to produce ciphertext E, wherein the IBE encryption engine uses as inputs the plaintext M, IBE public parameters, and an IBE public key associated with an intended recipient, wherein the IBE public key associated with the recipient includes a set of attributes w that correspond to conditions that the intended recipient is to satisfy before being permitted to perform decryption operations; and at a given recipient, running an IBE decryption engine with computing equipment to decrypt the ciphertext E to produce the plaintext M, wherein the IBE decryption engine uses as inputs the ciphertext E and an IBE private key SK associated with the given recipient, wherein the IBE private key SK contains IBE private key components, each of which corresponds to a respective attribute in an attribute set w′ of attributes of the given recipient, wherein w′ is not equal to w, and wherein in order to decrypt the ciphertext E to produce the plaintext M it is necessary that there is an overlap |w∩w′| between the attribute set w and the attribute set w′ that is equal to or greater than the attribute overlap threshold d.