Abstract: A peer-to-peer method and system for performing and managing backups in a network of nodes exploit excess disk capacity to perform peer-to-peer backup with no administrative costs. Each node minimizes storage overhead by selecting peer nodes that share substantial amounts of data. Common installations find suitable peer nodes and peer nodes with high overlap are identified. The method and system also provide mechanisms for confidentiality, integrity, and detection of failed or malicious peer nodes.

Abstract: A method and system to maintain portable computer data secure and an authentication token for use in the system are provided. The present invention provides for fine-grained authentication and full security of a laptop file system. The laptop disk is encrypted and each time data is fetched from the disk the laptop sends a short message requesting a decryption key from an authentication token worn or associated with the proper laptop user. If the user and his/her token are “present,” then access is allowed. If the user and his/her token are not “present” (i.e., within a predetermined radius), then access is disallowed and all in-memory data is flushed to the disk. The user wears the small authentication token that communicates with the laptop over a short-range, wireless link. Whenever the laptop needs decryption authority, it acquires it from the token; authority is retained only as long as necessary.

Abstract: Two embodiments of a method and system to maintain application data secure and authentication token for use therein are provided. The present invention uses transient authentication, in which a small hardware token continuously authenticates the user's presence over a short-range, wireless link. Four principles underlying transient authentication are described as well as the two embodiments for securing applications. In the first embodiment, applications are protected transparently by encrypting in-memory state when the user departs and decrypting this state when the user returns. This technique is effective, requiring just seconds to protect and restore an entire machine. In the second embodiment, applications utilize an API for transient authentication, protecting only sensitive state. Ports of three applications, PGP, SSH, and Mozilla are described with respect to this API.

Abstract: A peer-to-peer method and system for performing and managing backups in a network of nodes exploit excess disk capacity to perform peer-to-peer backup with no administrative costs. Each node minimizes storage overhead by selecting peer nodes that share substantial amounts of data. Common installations find suitable peer nodes and peer nodes with high overlap are identified. The method and system also provide mechanisms for confidentiality, integrity, and detection of failed or malicious peer nodes.

Abstract: Two embodiments of a method and system to maintain application data secure and authentication token for use therein are provided. The present invention uses transient authentication, in which a small hardware token continuously authenticates the user's presence over a short-range, wireless link. Four principles underlying transient authentication are described as well as the two embodiments for securing applications. In the first embodiment, applications are protected transparently by encrypting in-memory state when the user departs and decrypting this state when the user returns. This technique is effective, requiring just seconds to protect and restore an entire machine. In the second embodiment, applications utilize an API for transient authentication, protecting only sensitive state. Ports of three applications, PGP, SSH, and Mozilla are described with respect to this API.

Abstract: A method and system to maintain portable computer data secure and an authentication token for use in the system are provided. The present invention provides for fine-grained authentication and full security of a laptop file system. The laptop disk is encrypted and each time data is fetched from the disk the laptop sends a short message requesting a decryption key from an authentication token worn or associated with the proper laptop user. If the user and his/her token are “present,” then access is allowed. If the user and his/her token are not “present” (i.e., within a predetermined radius), then access is disallowed and all in-memory data is flushed to the disk. The user wears the small authentication token that communicates with the laptop over a short-range, wireless link. Whenever the laptop needs decryption authority, it acquires it from the token; authority is retained only as long as necessary.

Abstract: A tissue examination device includes a plurality of sensors, each of which produces a signal in response to pressure imposed on the sensor in accordance with the properties of different types of underlying tissue structures as the sensor is pressed against the tissue. A plurality of processing tests are performed on the signals, and the different types of the underlying tissue structures are discriminated from each other based on the results of the tests.

Abstract: Methods and devices are described for calibrating the pressure sensors of a tissue examination device to enable the sensors to produce signals that accurately indicate whether an underlying tissue structure is present in tissue being examined. In general, the calibration is performed using a substance configured to apply a selected amount of pressure to the sensors when engaged in a selected way by the tissue examination device. The sensors are calibrated based on levels of the signals produced in response to the selected amount of pressure imposed by the substance. The tissue examination device may be pressed against the substance, or the substance may be pressed against the sensors. Preferably, the substance applies the selected amount of pressure substantially uniformly to the sensors. A wide variety of substances can be used, such as a foam pad, a rubber pad, a gel, a fluid-containing balloon, and pressurized air.