SYSTEM AND METHOD FOR RECOGNIZING SPEECH SECURELY USING A SECURE MULTI-PARTY COMPUTATION PROTOCOL

A system and method recognizes speech securely using a secure multi-party computation protocol. The system includes a client and a server. The client is configured to provide securely speech in a form of an observation sequence of symbols, and the server is configured to provide securely a multiple trained hidden Markov models (HMMs), each trained HMM including a multiple states, a state transition probability distribution and an initial state distribution, and each state including a subset of the observation symbols and an observation symbol probability distribution. The observation symbol probability distributions are modeled by mixtures of Gaussian distributions. Also included are means for determining securely, for each HMM, a likelihood the observation sequence is produced by the states of the HMM, and means for determining a particular symbol with a maximum likelihood of a particular subset of the symbols corresponding to the speech.