Abstract: Disclosed is a method for evaluating resistance to cryptanalysis of a cipher structure having a diffusion element including a linear transformation placed between differently-sized confusion elements at an input and an output of the diffusion element. A generalized minimum number of non-zero symbols at the diffusion element's input and output is determined. The diffusion element's input is divided into subset inputs, each having a size corresponding to the size of each confusion element at the diffusion element input. For each subset input, a subset number of non-zero symbols at the subset input and the diffusion element output is determined. Each subset number is summed to generate a summed subset number. The summed subset number is subtracted from the generalized minimum number to generate a worst-case number. An upper bound of a maximum differential characteristic probability is calculated and used to evaluate the cipher structure.

Abstract: Embodiments describe a system and/or method for efficient classification of network packets. According to an aspect a method includes describing a packet as a feature vector and mapping the feature vector to a feature space. The method can further include defining a feature prism, classifying the packet relative to the feature prism, and determining if the feature vector matches the feature prism. If the feature vector matches the feature prism the packet is passed to a data recipient, if not, the packet is blocked. Another embodiment is an apparatus that includes an identification component that defines at least one feature of a packet and a classification component that classifies the packet based at least in part upon the at least one defined feature.

Abstract: An apparatus and method for identity reuse operable in a communications system, the method comprising selecting an identity value for a device; registering the device onto a network with the selected identity value; determining if the registration of the device is successful; and establishing a communication session for the device and deregistering the selected identity value upon termination of the communication session if the registration is successful, or determining whether to try a different identity value if the registration is not successful. In one aspect, the apparatus and method further comprising waiting a predetermined time period before either re-registering with the selected identity value or registering with the different identity value.

Abstract: An authentication system is disclosed. The authentication system includes a content provider configured to distribute encrypted content, wherein the encrypted content is generated using a content key, and a client having a symmetric key and configured to store the encrypted content received from the content provider and issue a request to the content provider, wherein the request includes a cryptographic function configured to have the symmetric key and the encrypted content as input, wherein the content provider is further configured to verify the client via the request to ensure that the client has received the encrypted content.

Abstract: A method, apparatus, and/or system are provided for establishing trust between an accessory device and a host device, using a global key known to both the host device and the accessory device, so that content protection for subscriber-based mobile broadcast services is provided. A secure link may be established between the accessory device and the host device so that when the accessory device receives encrypted content via a secured forward link only network, the accessory device may decrypt the content at the forward link only stack. The content is then re-encrypted/re-secured using one or more derived encryption keys and then sent to the host device where it may be decrypted and played back. A global key, unique to the particular device type of the host device, is employed to ultimately derive the session encryption keys used to re-encrypt/re-secure the content conveyed from the accessory device to the host device.

Abstract: Apparatus and method for generating a key stream is disclosed. In one embodiment, a cryptographic function is applied on input values selected from a first array of values to generate output values. Mask values are then selected from a second array of values and combined with the output values to generate a key stream block for the key stream. The first and second arrays are finite and may be implemented by a linear feedback shift register.

Abstract: Disclosed is a method for protecting sensitive data in a storage device having wear leveling. In the method, a write command, with an associated sensitive write signal indicating that sensitive data is associated with the write command, is received. The sensitive data is further associated with at least one address pointing to a storage location within an initial physical storage block. The write command is executed by writing to at least one storage location within an available physical storage block, pointing the at least one address to the at least one storage location within the available physical storage block, and erasing the initial physical storage block to complete execution of the write command.

Abstract: The REX cryptosystem presented herein is a variant of the NTRU cryptosystem. In the REX cryptosystem, a primary ring RXOR and two secondary rings RXOR,q and RXOR,p are used to reduce the number of operations required to compute the keys, to perform the encryption process, and to perform the decryption process. The REX cryptosystem may also be implemented using Walsh-Hadamard transformations to significantly increase speed.

Abstract: A block cipher is provided that secures data by encrypting it based on the memory address where it is to be stored. When encrypting data for storage in the memory address, the memory address is encrypted in a first plurality of block cipher rounds. Data round keys are generated using information from the first plurality of block cipher rounds. Data to be stored is combined with the encrypted memory address and encrypted in a second plurality of block cipher rounds using the data round keys. The encrypted data is then stored in the memory location. When decrypting data, the memory address is again encrypted as before while the encrypted stored data is decrypted in a second plurality of the block cipher rounds using the data round keys to obtain a partially decrypted data. The partially decrypted data is combined with the encrypted memory address to obtain fully decrypted data.

Abstract: Disclosed is a method for evaluating resistance to cryptanalysis of a cipher structure having a diffusion element including a linear transformation placed between differently-sized confusion elements at an input and an output of the diffusion element. A generalized minimum number of non-zero symbols at the diffusion element's input and output is determined. The diffusion element's input is divided into subset inputs, each having a size corresponding to the size of each confusion element at the diffusion element input. For each subset input, a subset number of non-zero symbols at the subset input and the diffusion element output is determined. Each subset number is summed to generate a summed subset number. The summed subset number is subtracted from the generalized minimum number to generate a worst-case number. An upper bound of a maximum differential characteristic probability is calculated and used to evaluate the cipher structure.

Abstract: Methods and apparatus are presented for encrypting and authenticating data, wherein some data is encrypted and some data is not encrypted, but all of the data is authenticated. Masking modules (410) are used in a partial-block encryption mode to indicate which bits of a data block are to be encrypted.

Abstract: A method for a server to initiate resynchronization with an access terminal, when synchronization has been lost, that cannot be exploited by attackers is provided. The server may provide the access terminal with a secret key that is only known to the access terminal and the server. The access terminal may store the secret key in a secure storage device to prevent the secret key from being hacked. If the server determines that synchronization has been lost, the server may send a resynchronization message to the access terminal with the secret key attached. The access terminal retrieves the stored secret key from the secure memory device and compares it to the secret key attached to the resynchronization message. If there is a match, the access terminal may initiate a secure communication link with the server to reestablish synchronization.

Abstract: A puzzle-based protocol is provided that allows a token and verifier to agree on a secure symmetric key for authentication between the token and verifier. A token stores a secret key and one or more puzzle-generating algorithms. The verifier independently obtains a plurality of puzzles associated with the token, pseudorandomly selects at least one of the puzzles, and solves it to obtain a puzzle secret and a puzzle identifier. The verifier generates a verifier key based on the puzzle secret. The verifier sends the puzzle identifier and an encoded version of the verifier key to the token. The token regenerates the puzzle secret using its puzzle-generating algorithms and the puzzle identifier. The token sends an encoded response to the verifier indicating that it knows the verifier key. The token and verifier may use the verifier key as a symmetric key for subsequent authentications.

Abstract: A network helper is provided that assists verifiers in executing a puzzle-based protocol for authentication of a token. A token stores a secret key and one or more puzzle-generating algorithms. The helper stores a plurality of puzzles associated with a particular token. When requested to do so by a verifier, the helper provides a plurality of pseudorandomly selected puzzles for the token to a verifier. The puzzles are encoded with information that is used between the verifier and token to establish a secured symmetric key. The verifier selects one or a few of the encoded puzzles and breaks them by a brute force attack. Because the helper does not know which puzzles have been selected, it has to break all puzzles to attempt to figure out the symmetric key. However, if a large number of puzzles are utilized, say millions, then breaking all of them becomes a computationally prohibitive task.

Abstract: Embodiments disclosed allow authentication between two entities having agreed on the use of a common modulus N. The authentication includes generating a pseudorandom string value; generating a public key value based on the modulus N and the pseudorandom string value; generating a private key value corresponding to the public key value; receiving a verifier's public key value; generating a shared secret value based on the modulus N, the private key value and the verifier's public key value; calculating an authentication signature value using the shared secret value; and transmitting the authentication signature value for authentication. When the authentication signature is received, the public key value and the shared value are generated to calculate an authentication signature value. Thereafter, the authentication signature values are compared and authenticated.

Abstract: A virtual environment and real world environment are combined into a framework that facilitates large-scale social interaction in multi-player fantasy games played in both the real world and/or a virtual world. Such combination of real and virtual world features may blend geo-caching, orienteering, and other virtual gaming features to enable players to interact across the real and virtual environments. A real world player is also mapped into the virtual environment, thereby inserting the player's movements and actions into the virtual environment. Additionally, this feature enables interaction between players located in a real environment with characters found in a virtual environment. A player may use a mobile device that is configured to recognize the geo-location and orientation of the player and display a corresponding view of the virtual environment gaming landscape for the player.

Abstract: Methods and apparatus are presented for encrypting and authenticating data, wherein some data is encrypted and some data is not encrypted, but all of the data is authenticated. Masking modules (410) are used in a partial-block encryption mode to indicate which bits of a data block are to be encrypted.

Abstract: Methods and apparatus are presented for secure, authenticated communication and data storage. The methods can be based on other methods such as IAPM, in which the encryption and authentication keys are of the same strength. In the HR-IAPM mode, a sender encrypts the data as in the IAPM mode using two encryption keys K0 and K1. The sender then XORs the plaintexts with corresponding ciphertexts, and combines the results to form a checksum This checksum is encrypted under the authentication key K2, this value is appended to the encrypted message as a message authentication code (MAC). The receiver decrypts as with IAPM, XORs the plaintexts with the corresponding ciphertexts and combines these values to form a checksum. The receiver then encrypts the checksum under the authentication key K2 and verifies that the resulting value agrees with the MAC. The HR mode allows blocks to be sent un-encrypted if desired.

Abstract: Methods and apparatus are presented for partially encrypting a data transmission, yet providing authentication for all of the data transmission. Plaintext blocks are combined with noise blocks and then either encrypted or decrypted to form ciphertext blocks and authentication blocks. The authentication blocks are used to determine a checksum that is then used to determine an authentication tag.

Abstract: Method and apparatus for secure transmissions. Each user is provided a registration key. A long-time updated broadcast key is encrypted using the registration key and provided periodically to a user. A short-time updated key is encrypted using the broadcast key and provided periodically to a user. Broadcasts are then encrypted using the short-time key, wherein the user decrypts the broadcast message using the short-time key. One embodiment provides link layer content encryption. Another embodiment provides end-to-end encryption.