Abstract: We present the first provably secure defense against software viruses. We hide a secret in the program code in a way that ensures that, as long as the system does not leak information about it, any injection of malware will destroy the secret with very?-high probability. Once the secret is destroyed, its destruction and therefore also the injection of malware will be quickly detected.

Abstract: Efficient secure password protocols are constructed that remain secure against offline dictionary attacks even when a large, but bounded, part of the storage of a server responsible for password verification is retrieved by an adversary through a remote or local connection. A registration algorithm and a verification algorithm accomplish the goal of defeating a dictionary attack. A password protocol where a server, on input of a login and a password, carefully selects several locations from the password files, properly combines their content according to some special function, and stores the result of this function as a tag that can be associated with this password and used in a verification phase to verify access by users.

Abstract: Systems, methods and programs for determining a question posed to a user during a user authentication process are provided. An example of a method for determining the question comprises obtaining user commercial activity, storing the user commercial activity by activity type, generating a set of candidate questions for a user based upon the user commercial activity, each candidate question in the set of candidate questions is associated with a score, selecting one candidate question from the set of the candidate questions based upon a first selection criteria, detecting a vendor placement opportunity in the selected candidate question by analyzing the user commercial activity and adding a vendor name into the selected candidate question based upon the detecting. The user commercial activity can be user purchases of goods and services from corresponding vendors. Lost Opportunities for the placement of an advertisement are detected and recorded.

Abstract: Various embodiments of the present invention for validating the authenticity of a website are provided. An example of a method according to the present invention comprises providing a website having an artifact, receiving a communication from a user, at a service provider, for validating the website associated with a service provider, inquiring from the user a description of the artifact comparing the artifact on the website with the description of the artifact from the user and generating a indication to the user based upon the comparing. The communication is over a first communication channel and the website is accessed over a second communication channel. The first communication channel is different than the second. The artifact can be displayed after a user session is identified.

Abstract: A method and software product for limit privacy loss due to data shared in a social network, where the basic underlying assumptions are that users are interested in sharing data and cannot be assumed to constantly follow appropriate privacy policies. Social networks deploy an additional layer of server-assisted access control which, even under no action from a user, automatically evolves over time, by restricting access to the user's data. The evolving access control mechanism provides non-trivial quantifiable guarantees for formally specified requirements of utility (i.e., users share as much data as possible to all other users) and privacy (i.e., users expose combinations of sensitive data only with low probability and over a long time).

Abstract: A method and software product for limit privacy loss due to data shared in a social network, where the basic underlying assumptions are that users are interested in sharing data and cannot be assumed to constantly follow appropriate privacy policies. Social networks deploy an additional layer of server-assisted access control which, even under no action from a user, automatically evolves over time, by restricting access to the user's data. The evolving access control mechanism provides non-trivial quantifiable guarantees for formally specified requirements of utility (i.e., users share as much data as possible to all other users) and privacy (i.e., users expose combinations of sensitive data only with low probability and over a long time).

Abstract: Disclosed are methods and systems for improving data security in a computer system. In particular, disclosed are methods and systems for writing a sequence of pseudorandom bits to a computer system's memory, where the number of bits written is equal to the expected size of the computer system's free memory. As such, if one or more unknown programs are resident in the computer system's memory, the methods and systems will be unable to write bits to the memory in which the unknown programs reside. Then, these methods and systems attempt to read these bits from the computer system's memory. Thus, if an unknown program is resident in the computer system's memory, the unknown program will have to correctly guess the bits that were attempted to be written in the memory in which the unknown program resides. Thus, if the read bits do not match the written bits, the existence of an unknown program may be determined.

Abstract: Disclosed are methods and systems for improving data security in a computer system. In particular, disclosed are methods and systems for writing a sequence of pseudorandom bits to a computer system's memory, where the number of bits written is equal to the expected size of the computer system's free memory. As such, if one or more unknown programs are resident in the computer system's memory, the methods and systems will be unable to write bits to the memory in which the unknown programs reside. Then, these methods and systems attempt to read these bits from the computer system's memory. Thus, if an unknown program is resident in the computer system's memory, the unknown program will have to correctly guess the bits that were attempted to be written in the memory in which the unknown program resides. Thus, if the read bits do not match the written bits, the existence of an unknown program may be determined.

Abstract: A system enables a user to remove a file from a file system and from all backup tapes without ever mounting a single tape. When a file is backed up, it is first encrypted using a randomly generated key and then backed up. When the user wishes to remove the file from the backup tape, the key used to encrypt the file is deleted. Deleting the encryption key renders the data on the tape inaccessible. No one, including the file owner, can ever access the file again. The encrypt before-backup method is completely transparent to the user. Only the computer system's operating system knows which key was used to encrypt the file during backup. This ensures that when the operating system is instructed to delete the encryption key, the key is "lost" forever and thus the backed up files become unreadable. Unlike prior cryptographic file systems, the revoked backup files are inaccessible to both the user and others.

Abstract: A certificate, calculated on the text of a document to be reproduced, is included in the document in a form which is machine-readable. Upon optical character recognition scanning, or other digitizing reproduction, the certificate is also scanned and stored for comparison. A new certificate is calculated on the contents of the reproduced document and compared to the scanned certificate. If the two certificates are different, it is known that at least one error exists in the reproduced document. More than one certificate can be provided for a document in order to facilitate error location on the document and error correction therein.

Abstract: A certificate, calculated on the text of a document to be reproduced, is included in the document in a form which is machine-readable. Upon optical character recognition scanning, or other digitizing reproduction, the certificate is also scanned and stored for comparison. A new certificate is calculated on the contents of the reproduced document and compared to the scanned certificate. If the two certificates are different, it is known that at least one error exists in the reproduced document. More than one certificate can be provided for a document in order to facilitate error location on the document and error correction therein.

Abstract: Independent heterogeneous computers are interconnected for oblivious, high speed, long distance communications. A printed circuit board with onboard RAM repeats all write commands through a data transmission media to a remote system. Each read and write cycle of the communicating computer is completed locally (using only local RAM). Apart from repeating write commands to a remote system, the invention is oblivious to the remote system. Data is transmitted from one machine to another without expensive communication protocols or transmission line latency induced wait states. A remote computer accesses network data only after it has been transmitted and stored in local memory. Multiple data transfers can be pipelined, that is, multiple datum may simultaneously reside in a high latency network/long transmission line. Although the time required to transmit any single datum remains proportional to the signal propagation delay, the time required to transmit multiple data is significantly reduced.