Abstract: An encryption and cryptosystem for fast and efficient searching of ciphertexts. Unencrypted secret data may be transformed into encoded secret data using an injective encoding such that each distinct value of the unencrypted secret data is mapped to a unique index in the encoded secret data. The encoded secret data may be homomorphically encrypted using the homomorphic encryption key to generate secret data ciphertexts. The secret data ciphertexts may be transmitted to an external system for searching the secret data ciphertexts for encoded queries. The encoded queries are encoded by the same injective encoding as the secret data, to directly search only indices of the secret data ciphertexts corresponding to query indices having non-zero query values, to detect if values of the secret data ciphertexts match values of the encoded queries at the query indices, without searching the remaining indices of the secret data ciphertexts.

Abstract: A multi-party system, devices, and method for token-based obfuscation of secret information. A first party device may store a secret original program T and original data D, retrieve a set of secret keys SK, obfuscate the original program T with the set of secret keys SK to generate an obfuscated program T?, obfuscate the original data D with the set of secret keys SK to generate a token of the data Token(D), and transfer the obfuscated program T? and Token(D) to a second party device. The second party device may evaluate the obfuscated program T? on the token of the data Token(D) to generate a result equivalent to evaluating the original program T on the original data D if the same set of secret keys SK is used to obfuscate the original program T and the original data D, without exposing the original program T to the second party.

Abstract: An encryption and cryptosystem for fast and efficient searching of ciphertexts. Unencrypted secret data may be transformed into encoded secret data using an injective encoding such that each distinct value of the unencrypted secret data is mapped to a unique index in the encoded secret data. The encoded secret data may be homomorphically encrypted using the homomorphic encryption key to generate secret data ciphertexts. The secret data ciphertexts may be transmitted to an external system for searching the secret data ciphertexts for encoded queries. The encoded queries are encoded by the same injective encoding as the secret data, to directly search only indices of the secret data ciphertexts corresponding to query indices having non-zero query values, to detect if values of the secret data ciphertexts match values of the encoded queries at the query indices, without searching the remaining indices of the secret data ciphertexts.

Abstract: A multi-party system, devices, and method for token-based obfuscation of secret information. A first party device may store a secret original program T and original data D, retrieve a set of secret keys SK, obfuscate the original program T with the set of secret keys SK to generate an obfuscated program T?, obfuscate the original data D with the set of secret keys SK to generate a token of the data Token(D), and transfer the obfuscated program T? and Token(D) to a second party device. The second party device may evaluate the obfuscated program T? on the token of the data Token(D) to generate a result equivalent to evaluating the original program T on the original data D if the same set of secret keys SK is used to obfuscate the original program T and the original data D, without exposing the original program T to the second party.

Abstract: A method, apparatus and computer program product for providing one-time programs is presented. A program to be converted to a new program having a predetermined lifetime is identified. The program is compiled to produce the new program having a predetermined lifetime and wherein the new program having a predetermined lifetime is guaranteed to only have the predetermined lifetime.

Abstract: A method includes searching in the ZN domain, for N greater than 2, for heavy Fourier coefficients of a function. The method may be implemented for any type of signal compression, such as image, video or audio compression. It may also be used to decode corrupted codewords.

Abstract: Methods for designing encryption algorithms with different levels of security for different parties: "easier" (but requiring some work nonetheless) to break for some parties (e.g., the government) than for other parties (the adversaries at large). This is achieved by a new form of key escrow in which the government gets some information related to the secret keys of individuals but not the secret keys themselves. The information given to the government enables it to decrypt with a predetermined level of computational difficulty less than that for adversaries at large. The new key escrow methods are verifiable. Verification information can be provided to the government so that it can verify that the information escrowed is sufficient to enable it to decrypt with the predetermined level of computational difficulty. The fact that the government must perform some computation to break the encryption schemes of individual users provides a serious deterrent against massive wiretapping.

Abstract: In a multiparty verification system, a prover and a verifier are coupled to rocess respective outputs to provide a system output such as an identification verification. The prover is formed of plural units which share confidential information used to encrypt information carried by the prover. Communication between the prover units is prevented. The first prover unit encrypts the information based on additional information received from the verifier and transfers the encrypted information to the verifier. Subsequently, the verifier obtains from the second prover unit the shared confidential information required to decrypt a subset of the transmitted encrypted information.