Abstract: A method of private mutually authenticated key exchange is provided. The method may include receiving, at the first device, a message transmitted from a second device and including a hierarchical inner-product encryption (HIPE) ciphertext. Further, the method may include decrypting, at the first device, the HIPE ciphertext to generate a first authenticated encryption (AE) ciphertext. The method may further include decrypting, at the first device, the first AE ciphertext. Further, the method may include encrypting, at the first device, a second AE ciphertext including a signature and one or more attributes of the first device. Moreover, the method may include transmitting, to the second device, another message including the second AE ciphertext.

Abstract: A method of private mutually authenticated key exchange is provided. The method may include receiving, at the first device, a message transmitted from a second device and including a hierarchical inner-product encryption (HIPE) ciphertext. Further, the method may include decrypting, at the first device, the HIPE ciphertext to generate a first authenticated encryption (AE) ciphertext. The method may further include decrypting, at the first device, the first AE ciphertext. Further, the method may include encrypting, at the first device, a second AE ciphertext including a signature and one or more attributes of the first device. Moreover, the method may include transmitting, to the second device, another message including the second AE ciphertext.

Abstract: A method for encrypting programming in which a controlled number of unintended recipients of a broadcast are allowed to view a program so that a set of encryption keys can be found which enables a broadcaster to more quickly broadcast the program to its intended paying recipients than conventional encryption methods which only allow programs to be viewed by its intended recipients. To find the set of keys, a broadcaster first determines an acceptable f-ratio of a total number of viewers of the broadcast program to a number of intended viewers in an identified target set who paid to receive the program. The target set of viewers is included in the total number of viewers. The broadcaster then constructs an f-redundant establishment key allocation set from which the establishment keys for encrypting the program are selected.