International Business Machines Corporation

Tal D Rabin

Hugo M Krawczyk

Rosario Gennaro

Ashish Jagmohan

Demijan Klinc

Camit Hazay

Shai Halevi

Suresh N Chari

Pankaj Rohatgi

Vincenzo Valentino DiLuoffo

Charanjit Singh Jutla

Josyula R Rao

Elaine Rivette Palmer

Paul Ashley Karger

Michael Steiner

David Claude Toll

Helmut Scherzer

Juan Alberto Garay

Hugo Mario Krawczyk

Stephane Herman Maes

Dakshi Agrawal

Chatschik Bisdikian

Murtaza Zafer

Jeffrey Scott Sorensen

Firas Bouz

Terry Dwain Escamilla

Cagatay Capar

A method, system and computer program product are disclosed for compressing encrypted data, wherein the data is encrypted by using a block encryption algorithm in a chained mode of operation, and the encrypted data is comprised of a set of N encrypted blocks, C. . . C. In one embodiment, the method comprises leaving block Cuncompressed, and compressing all of the blocks C. . . Cin a defined sequence using a Slepian-Wolf code. In an embodiment, the data is encrypted using an encryption key K, and the compressing includes compressing all of the blocks C. . . Cwithout using the encryption key. In one embodiment, the compressing includes outputting the blocks C. . . Cas a set of compressed blocks CmprC. . . CmprC, and the method further comprises decrypting Cto generate a reconstructed block {tilde over (X)}, and decrypting and decompressing the set of compressed blocks using {tilde over (X)}.

Compressing encrypted data without the encryption key

Compressing block-cipher encrypted data

Embodiments of the invention provide for authenticating users of web-based applications by presenting a previously acquired signed digital signature. Examples establish secure user sessions between a client and a user in response to a verification of an identification of the user by the client, the client creating a unique username for the user and unlocking access by the user to a client digital signature for use with a request for service from a third party web server. A secure facilitator session is established between the client and a third party web server, wherein messages exchanged with the unique username and a unique session identification indicia of the secure facilitator session signed by the unlocked digital signature result in executed processes requested by the service identifier data if the messages are validated without the client requiring the user to verify user identification for any message until a secure facilitator session ends.

Remote authentication based on challenge-response using digital certificates

A mechanism is provided for establishing a shared secret-key for secure communication between nodes in a wireless network. A first node in the wireless network provides a spreading code to a second node of the wireless network. The second node provides a first input for the key establishment to the first node using communication encoded with the spreading code. Responsive to obtaining the first input from the second node, the first node provides a second input for the key establishment to the second node using communication encoded with the spreading code. Then, the first node and the second node establish the shared secret-key using the first input and the second input.

Secret-key exchange for wireless and sensor networks

A pairwise key-agreement scheme is provided for creating key agreements non-interactively between pairs of nodes disposed in a hierarchy of nodes. The scheme is non-interactive so that any two nodes can agree on a shared secret key without interaction. In addition, the scheme is identity-based so that any given node only needs to know the identity of peer nodes to compute the shared secret key. All of the nodes are arranged in a hierarchy where an intermediate node in the hierarchy can derive the secret keys for each of its children from its own secret key and the identity of the child. Accordingly, the scheme is fully resilient against compromise of any number of leaves in the hierarchy and of a threshold number of nodes in the upper levels of the hierarchy. The scheme is well-suited for environments such as mobile ad-hoc networks (MANETs), which are very dynamic, have acute bandwidth-constraints and have many nodes are vulnerable to compromise.

Non-interactive hierarchical identity-based key-agreement

A random number generator (RNG) resistant to side channel attacks includes an activation pseudo random number generator (APRNG) having an activation output connected to an activation seed input to provide a next seed to the activation seed input. A second random number generator includes a second seed input, which receives the next seed and a random data output, which outputs random data in accordance with the next seed. An input seed memory is connected to the activation seed input and a feedback connection from the activation output so that the next seed is stored in the input seed memory to be used by the APRNG as the activation seed input at a next startup cycle.

Method, apparatus and system for resistance to side channel attacks on random number generators

This invention is a method and apparatus which provide a solution to the problem of constructing efficient and secure digital signature schemes. It presents a signature scheme that can be proven to be existentially unforgeable under a chosen message attack, assuming a variant of the RSA conjecture. This scheme is not based on &ldquo;signature trees&rdquo;, but instead it uses a &ldquo;hash-and-sign&rdquo; paradigm, while maintaining provable security. The security proof is based on well-defined and reasonable assumptions made on the cryptographic hash function in use. In particular, it does not model this function as a random oracle. The signature scheme which is described in this invention is efficient. Further, it is &ldquo;stateless&rdquo;, in the sense that the signer does not need to keep any state, other than the secret key, for the purpose of generating signatures.

Secure hash-and-sign signatures

A method of performing biometric authentication of a person's identity including a biometric template prior to storing it in a biometric database. The encryption algorithm encrypts the biometric template using a pass-phrase, known only to the individual, to generate the cryptographic key used to store and retrieve the biometric template. When an individual wishes to access a secured resource, he must be authenticated by providing an identifier which is used to retrieve the appropriate record. He must also provide the correct password to allow the system to decrypt the model.

Biometric authentication system with encrypted models

A signer uses an undeniable signature scheme to sign his public key to thereby create an &ldquo;undeniable certificate&rdquo; which can be used to verify the signer's digital signature on any message signed using the signer's corresponding private key. Hence, once the undeniable certificate is received by the recipient, the recipient and the signer engage one time in a confirmation protocol or denial protocol to the satisfaction of the recipient that the undeniable certificate has in fact been signed by the signer thus certifying signer's public key. Thereafter, the recipient can use the certified public key to verify any documents signed by the signer with no further interaction with the signer. However, third parties are precluded from verifying the signer's signature since they do not possess the confirmed undeniable certificate and corresponding public key. Digital signatures can now be verified between two parties using a public key as in traditional digital signatures but which avoids verifiability by third parties.

Undeniable certificates for digital signature verification

A solution to the general problem of Secure Storage and Retrieval of Information (SSRI) guarantees that also the process of storing the information is correct even when some processors fail. A user interacts with the storage system by depositing a file and receiving a proof that the deposit was correctly executed. The user interacts with a single distinguished processor called the gateway. The mechanism enables storage in the presence of both inactive and maliciously active faults, while maintaining (asymptotical) space optimailty. This mechanism is enhanced with the added requirement of confidentiality of information; i.e., that a collusion of processors should not be able to learn anything about the information. Also, in this case space optimality is preserved.

Method and apparatus for the secure distributed storage and retrieval of information

A method for providing a digital signature, 'chameleon signatures', which provide the signer of a digital signature exclusive control to disclose the contents of the signed information to third parties. The signatures are closely related to 'undeniable signatures', but allow for simpler and more efficient realizations. The method is essentially non-interactive requiring no communication between sender and receiver and do not involve the design and complexity of zero knowledge proofs on which traditional undeniable signatures are based. The method employs a combination of standard digital signing methods with a unique hash functions. These hash functions are characterized by the non-standard property of being collision resistant for the signer but collision tractable for the recipient.

Chameleon hashing and signatures

Method and apparatus for the secure distributed storage and retrieval of

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Riverdale, NY, United States of America

Tal D Rabin