Abstract: Methods and apparatus are provided for secure and reliable transmission of messages over a silent alarm channel. A plurality of messages are transmitted by obtaining the plurality of messages; and transmitting the plurality of messages on a forward-secure channel to a receiver, wherein the forward-secure channel comprises a buffer having a plurality of entries, wherein each of the entries stores one of the messages and wherein at least one of the plurality of messages is maintained in the forward-secure channel after a receiver reads the channel. Two levels of encryption are optionally performed on the forward-secure channel. The messages carried by the disclosed silent alarm channels can comprise, for example, (i) entries in a security log; (ii) one-time passwords derived by authentication tokens; or (iii) tampering notifications from one or more sensor devices.

Abstract: A technique provides authentication codes to authenticate a user to an authentication server. The technique involves generating, by an electronic apparatus (e.g., a smart phone, a tablet, a laptop, etc.), token codes from a cryptographic key. The technique further involves obtaining biometric measurements from a user, and outputting composite passcodes as the authentication codes. The composite passcodes include the token codes and biometric factors based on the biometric measurements. Additionally, the token codes and the biometric factors of the composite passcodes operate as authentication inputs to user authentication operations performed by the authentication server. In some arrangements, the biometric factors are results of facial recognition (e.g., via a camera), voice recognition (e.g., via a microphone), gate recognition (e.g., via an accelerometer), touch recognition and/or typing recognition (e.g., via a touchscreen or keyboard), combinations thereof, etc.

Abstract: A technique for detecting unauthorized copies of a soft token that runs on a mobile device includes generating a set of random bits on the mobile device and providing samples of the set of random bits, as well as token codes from the soft token, for delivery to a server during authentication requests. The server acquires the set of random bits of the mobile device, or learns the set of random bits over the course of multiple login attempts. Thereafter, the server predicts values of the samples of the set of random bits and tests actual samples arriving in connection with subsequent authentication requests. Mismatches between predicted samples and received samples indicate discrepancies between the random bits of the device providing the samples and the random bits of the mobile device, and thus indicate unauthorized soft token copies.

Abstract: In one exemplary embodiment, an apparatus includes a memory storing data and a processor performing operations. The apparatus generates or maintains an accumulation tree for the stored data—an ordered tree structure with a root node, leaf nodes and internal nodes. Each leaf node corresponds to a portion of the data. A depth of the tree remains constant. A bound on a degree of each internal node is a function of a number of leaf nodes of a subtree rooted at the internal node. Each node of the tree has an accumulation value. Accumulation values of the root and internal nodes are determined by hierarchically employing an accumulator over the accumulation values of the nodes lying one level below the node in question. The accumulation value of the root node is a digest for the tree.

Abstract: An improved technique for assessing the security status of a device on which a soft token is run collects device posture information from the device running the soft token and initiates transmission of the device posture information to a server to be used in assessing whether the device has been subjected to malicious activity. The device posture information may relate to the software status, hardware status, and/or environmental context of the device. In some examples, the device posture information is transmitted to the server directly. In other examples, the device posture information is transmitted to the server via auxiliary bits embedded in passcodes displayed to the user, which the user may read and transfer to the server as part of authentication requests. The server may apply the device posture information in a number of areas, including, for example, authentication management, risk assessment, and/or security analytics.

Abstract: An improved technique provides scheduled data transfer between a mobile device and a server. The mobile device combines token codes generated by a soft token with sequences of auxiliary bits and displays the combinations to users as passcodes. Users may then copy the passcodes to their computers for authenticating to a server on a remote network. As the passcodes include both token codes and sequences of auxiliary bits, a communication channel is established whereby the auxiliary bits as well as the soft token codes are transmitted from the mobile device to the server.

Abstract: A system and method for cryptographically checking the correctness of outsourced set operations performed by an untrusted server over a dynamic collection of sets that are owned (and updated) by a trusted source is disclosed. The system and method provides new authentication mechanisms that allow any entity to publicly verify a proof attesting the correctness of primitive set operations such as intersection, union, subset and set difference. Based on a novel extension of the security properties of bilinear-map accumulators as well as on a primitive called accumulation tree, the system and method achieves optimal verification and proof complexity, as well as optimal update complexity, while incurring no extra asymptotic space overhead. The method provides an efficient proof construction, adding a logarithmic overhead to the computation of the answer of a set-operation query. Applications of interest include efficient verification of keyword search and database queries.

Abstract: A system and method for cryptographically checking the correctness of outsourced set operations performed by an untrusted server over a dynamic collection of sets that are owned (and updated) by a trusted source is disclosed. The system and method provides new authentication mechanisms that allow any entity to publicly verify a proof attesting the correctness of primitive set operations such as intersection, union, subset and set difference. Based on a novel extension of the security properties of bilinear-map accumulators as well as on a primitive called accumulation tree, the system and method achieves optimal verification and proof complexity, as well as optimal update complexity, while incurring no extra asymptotic space overhead. The method provides an efficient proof construction, adding a logarithmic overhead to the computation of the answer of a set-operation query. Applications of interest include efficient verification of keyword search and database queries.

Abstract: In one exemplary embodiment, an apparatus includes a memory storing data and a processor performing operations. The apparatus generates or maintains an accumulation tree for the stored data—an ordered tree structure with a root node, leaf nodes and internal nodes. Each leaf node corresponds to a portion of the data. A depth of the tree remains constant. A bound on a degree of each internal node is a function of a number of leaf nodes of a subtree rooted at the internal node. Each node of the tree has an accumulation value. Accumulation values of the root and internal nodes are determined by hierarchically employing an accumulator over the accumulation values of the nodes lying one level below the node in question. The accumulation value of the root node is a digest for the tree.

Abstract: In one exemplary embodiment, a method includes: providing an abstract tree structure having a root node, tree nodes, and leaf nodes, each leaf node corresponds to a portion of data; mapping first network nodes of a distributed network to the tree nodes; mapping second network nodes to the leaf nodes; assigning unique identifiers to the root node, tree nodes, and leaf nodes; storing, at each first network node, the unique identifier of the corresponding tree node, the unique identifier of a parent, and the unique identifiers of children; storing, at each second network node, the portion of data and path information; providing a distributed hash tree wherein the DHT includes a hash value for each node of the ATS signing the top hash value for the root node; and storing, at each second network node, the corresponding hash value of the tree node and the hash values of children.

Abstract: A method and distributed network are provided.