US Patent 10205713 Private and mutually authenticated key exchange

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.