Bell Communications Research, Inc.

At&t Intellectual Property I, L.p.

At+t Corp.

Telcordia Technologies, Inc.

William A Aiello

Ramarathnam R Venkatesan

Aviel D Rubin

Martin Joel Strauss

Charles Robert Kalmanek, Jr

Oliver Spatscheck

Subhabrata Bapi Sen

Jacobus Erasmus Van Der Merwe

William J Leighton, Iii

Patrick Drew McDaniel

William Todd Marshall

Steven Michael Bellovin

Rafail Ostrovsky

Sivaramakrishnan Rajagopalan

Sachin Lodha

Aviel Q Rubin

Sivaramakrishnam Rajagopalan

William J Leighton

Charles Robert Kalmanek

Patrick Mcdaniel

An application provisioning device may be used to manage a profile of a host and provide data corresponding to a selected application for installation at a host. A reverse firewall may use the profile of the host to determine whether to allow or block particular network communication from an application running on the host. An indication of a selected application may be received at the application provisioning device. Configuration information may also be received at the application provisioning device. The application provisioning server may request an update to the profile of a host and transmit such a request. The profile may be updated to reflect the configuration information and/or information of the selected application. Data corresponding to the selected application may be updated and transmitted to a host computer, where it may be installed. Therefore, the installed application running on the host may operate without being prematurely blocked by the reverse firewall.

Reverse firewall with self-provisioning

The present intention permits a user to conduct remote transactions without a network while using an untrusted computing device, such as a hand held personal digital assistant or a laptop computer. The computing device is augmented with a smartcard reader, and the user obtains a smartcard and connects it to the device. This design can be used by an untrusted user to perform financial transactions, such as placing bets on the outcome of a probabilistic computation. Protocols are presented for adding (purchasing) or removing (selling) value on the smartcard, again without requiring a network connection. Using the instant protocols, neither the user nor the entity issuing the smartcards can benefit from cheating.

Using smartcards to enable probabilistic transactions on an untrusted device

The present invention permits a user to conduct remote transactions without a network while using an untrusted computing device, such as a hand-held personal digital assistant or a laptop computer. The computing device is augmented with a smartcard reader, and the user obtains a smartcard and connects it to the device. This design can be used by an untrusted user to perform financial transactions, such as placing bets on the outcome of a probabilistic computation. Protocols are presented for adding (purchasing) or removing (selling) value on the smartcard, again without requiring a network connection. Using the instant protocols, neither the user nor the entity issuing the smartcards can benefit from cheating.

The broadband telephony interface is provisioned by receiving information authenticating a provisioning server, establishing a communication channel between the user and the provisioning server over which is transmitted authorization information from the user to the provisioning server, and encrypting and transmitting a cryptographic key associated with the user to the provisioning server. The cryptographic key can be a symmetric key or a public key corresponding to a private key stored in the broadband telephony interface. The cryptographic key can be utilized to generate other keys which are utilized to secure communication channels for the telephony service. The broadband telephony interface advantageously can be implemented as untrusted hardware or software that is installed by a customer.

Method and apparatus for enhanced security in a broadband telephony network

The present method permits a user to conduct remote transactions without a network while using an untrusted computing device, such as a hand-held personal digital assistant or a laptop computer. The computing device is augmented with a smartcard reader, and the user obtains a smartcard and connects it to the device. This design can be used by an untrusted user to perform financial transactions, such as placing bets on the outcome of a probabilistic computation. Protocols are presented for adding (purchasing) or removing (selling) value on the smartcard, again without requiring a network connection. Using the instant protocols, neither the user nor the entity issuing the smartcards can benefit from cheating.

Using smartcards to enable probabilistic transaction on an untrusted device

Method for efficiently revoking digital identities

A pseudo-random number generator is used as a pre-processing step to generating a long random bit string. The bit string is then 'stretched' by performing certain one-way functions in parallel on the bit strings. In a preferred embodiment, specialized constructions based on expander graphs are also used. Preferably, the strings generated by the one-way functions and expander graphs are exclusive-ored. An embodiment may operate in the following manner. Assume a slow but secure generator G.sub.0.

Cryptographically secure pseudo-random bit generator for fast and secure

A secure hash function according to the present invention uses a stretch function 202 and a compression function 202 to provide a secure hash value. A stretch function is a function which increases an input string (pre-image). In one version of the invention, a stretch function .function. maps l-bit inputs into 2m bit, where 2m&gt;l. Preferably, the stretch function .function. is one-way. The stretch function randomizes the input string. The output of the stretch function is fed into a compression function c, which compresses the stretch function output from 2m bits to 2n bits, where m&gt;n. The compression function is preferably a cryptographic primitive selected from a family of compression functions. In a preferred embodiment, a standard key scheduling algorithm of the cryptographic compression function (such as DES) is replaced and an output of the stretch function is used as the key. The inventors find that using a stretch function output as the compression function key improves the security of the compression function. Moreover, because the stretch function output randomizes the input string, the security constraints on the compression function are less stringent. As a result, an efficient, simple, and secure hash function is provided.

Method and apparatus for generating secure hash functions

Methodology and concomitant circuitry to generate cryptographically strong pseudo-random bit streams utilize secure block cypher encoders. Each block cypher encoder has a random key and a first seed as an input, and the output of each encoder is fed back to connect to its input. The first seed serves as the initial input, and each subsequent input is the immediate output of the block cypher encoder. Each bit in the cryptographically strong pseudo-random bit stream is related to a first inner product between input to the block cypher encoder and a second seed and a second inner product between the random key and a third seed.

Pseudo-random generator

Methods and circuitry for generating a cryptographic hash function using a strong pseudo-random generator along with the input data to create high quality pseudo-random keys as indices to pseudo-random functions, as well as a pseudo-random function from 2n bits to 2n bits given a pseudo-random function from n bits to n bits.

Efficient cryptographic hash functions and methods for amplifying the

A method for generating random bits which is as fast as popular generators and which has provable strong properties. The method makes use of the unpredictability properties of a relatively slow cryptographically strong generator and the rapid mixing properties of random walks on expander graphs. Use of the cryptographically strong generator is typically restricted to a small off-line or a preprocessing step. Subsequent bits are produced with a few register operations per bit. The method and concomitant generator are useful in at least two different types of applications: for faster reliable simulations (or randomizing algorithms), and cryptographic/encryption schemes.

Methodology and concomitant circuitry to generate cryptographically strong pseudo-random bit streams utilize secure block cypher encoders. Typically, each block cypher encoder has a first seed and a random key as an input. In the most basic realization of the methodology and circuitry, the output of each encoder is fed back to connect to its input. The first seed serves as the initial input, and each subsequent input is the immediate output. Each bit in the cryptographically strong pseudo-random bit stream is related to an inner product between each input to the encoder and a second seed.

Growing community of inventors

Madison, NJ, United States of America

William A Aiello