Abstract: An arrangement and methods of using a sensor as a PUF is described. The sensor includes individually addressable sub elements. The sensor's output signal is a function of the response of its individually addressable sub elements, but the individual responses of sub elements are used as a CRP generation mechanism. Responses from the pairs of individually addressable sensor elements over ranges of environmental inputs are a unique sensor fingerprint and may be used for authentication, encrypted communication and for hardware tracking, as well as for detection of bad portions of the sensor or error injection attacks.

Abstract: Systems and methods for the generation and use of session keys supporting secure communications between a client and server device are disclosed. The client hashes each of a series of passwords a first number of times. The hashed passwords are sent to a server. The server applies the hashed password to an array of PUF devices, and receives an initial response bitstream which is stored. The client later hashes each of the series of passwords a second number of times, which is less than the first number, and these are sent to the server. The server continues to hash the second message digest, generate PUF responses, and compare the result to the initially stored responses. For each password, the number of hashes necessary to achieve a match is a partial session key. Latency is improved by an array of separately addressable PUFs, each producing a partial session key.

Abstract: Methods for applying one-way functions for the purposes of cryptography and authentication are disclosed. The methods may be used in cryptographic systems relying on physical unclonable functions or the measurement of biological objects where repeated, sequential applications of one-way functions is required. Under the method, an input bitstream is received. The bitstream may optionally be expanded with a binary nonce and may be optionally transformed into a balanced ternary stream. A polynomial is generated having coefficients that are the values encoded in the stream. The polynomial is raised to a power to generate a second polynomial, and the coefficients of the second polynomial are read as an output stream.

Abstract: Systems and methods for the generation and use of session keys supporting secure communications between a client and server device are disclosed. The client hashes each of a series of passwords a first number of times. The hashed passwords are sent to a server. The server applies the hashed password to an array of PUF devices, and receives an initial response bitstream which is stored. The client later hashes each of the series of passwords a second number of times, which is less than the first number, and these are sent to the server. The server continues to hash the second message digest, generate PUF responses, and compare the result to the initially stored responses. For each password, the number of hashes necessary to achieve a match is a partial session key. Latency is improved by an array of separately addressable PUFs, each producing a partial session key.