Abstract: Systems and methods of correcting errors in encrypted communication between a server and client devices using keyless encryption schemes are disclosed. Client devices with arrays of physical-unclonable-function devices respond to challenges from a server. Characteristics of the arrays are stored by the server during a secure enrollment process. To send an encrypted message, the server generates a message digest, extracts data from the stored arrays on the basis of the message digest, applies error correction codes to the message, encrypts the message with the extracted data, and sends the message to a client. The server may receive a handshake containing all or part of the message digest, measures its PUF, and decrypts and decodes the message.

Abstract: The present invention provides a method for using a tamper-resistant physical unclonable functions (PUF) to generate temporary passwords, encrypt a password manager database for one-way encryption, and authenticate users. Resistive Random-Access Memory (ReRAM) can be exploited as PUFs. On the server side, a ReRAM PUF can be used to change the format of the password manager database. By comparing the resistance values extracted from the ReRAM PUF, a bitstream can be generated which can then be used as a challenge. Furthermore, by utilizing the hash function and the ReRAM PUF, the password manager database's content can be encrypted as a one-way encryption. The resistance values, which are the ReRAM PUF output, are converted to a bitstream and then replace the user ID and password hash in the database.

Abstract: Systems and methods for providing authentication and secure cryptographic communication between a client and server are described. The client includes an addressable array of PUF devices. The client receives or generates a set of instructions usable to determine a range of PUF addresses. The client measures the PUF addresses and generates a first set of responses. The responses are used to encrypt a session key, which is stored, along with the instructions and a hash of the responses, at the client. Later, the client may recover the session key by using the instructions to measure the PUF again, resulting in a second set of responses. Using a response-based cryptography search engine, the client may then iteratively modify and hash the second set of responses until a response set is uncovered that matches the first response set. This modified response set may then be used to uncover the session key.

Abstract: Systems and methods of correcting errors in encrypted communication between a server and client devices using keyless encryption schemes are disclosed. Client devices with arrays of physical-unclonable-function devices respond to challenges from a server. Characteristics of the arrays are stored by the server during a secure enrollment process. To send an encrypted message, the server generates a message digest, extracts data from the stored arrays on the basis of the message digest, applies error correction codes to the message, encrypts the message with the extracted data, and sends the message to a client. The server may receive a handshake containing all or part of the message digest, measures its PUF, and decrypts and decodes the message.

Abstract: The use of pre-formed arrays of memristors such as ReRAMs for true random number generation is disclosed. The method exploits the natural randomness in the large stochastic cell-to-cell variations in resistance values at low injected current in the pre-formed range. This novel TRNG scheme can be designed with three interconnected blocks: i) a pseudo-random number generator (PRNG) that is acting as an extended output function (XOF) to generate a stream of addresses pointing randomly at the array of ReRAM cells; ii) a method to read the resistance values of these cells at low injected current and convert the values in a stream of random bits; and, if needed, iii) methods to further enhance the randomness of this stream such as, but not limited to, mathematical, Boolean, and cryptographic algorithms.