Physical key-protected one time pad

• US 9,054,871 B2
• Filed: 02/21/2013
• Issued: 06/09/2015
• Est. Priority Date: 02/21/2012
• Status: Active Grant

• Current Assignee: London School of Hygiene and Tropical Medicine (University of London)
• Original Assignee: California Institute of Technology, London School of Hygiene and Tropical Medicine (University of London)
• Inventors: Horstmeyer, Roarke, Judkewitz, Benjamin, Yang, Changhuei, Vellekoop, Ivo M.
• Primary Examiner(s): Rashid, Harunur
• Assistant Examiner(s): HOLMES, ANGELA R
• Application Number:
  US13/773,490
• Publication Number:
  US 20130243187A1
• Time in Patent Office: 838 Days
• Field of Search: 380/28, 372/29.014
• US Class Current: 1/1
• CPC Class Codes: G09C 1/00 Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system cryptographic typewriters G09C3/00
• CPC Class Codes: G09C 5/00 Ciphering apparatus or methods not provided for in the preceding groups, e.g. involving the concealment or deformation of graphic data such as designs, written or printed messages
• CPC Class Codes: H04L 27/2278 using correlation techniques, e.g. for spread spectrum signals
• CPC Class Codes: H04L 27/3818 using coherent demodulation, i.e. using one or more nominally phase synchronous carriers H04L27/227 and H04L27/389 take precedence
• CPC Class Codes: H04L 9/0656 Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher
• CPC Class Codes: H04L 9/0841 involving Diffie-Hellman or related key agreement protocols
• CPC Class Codes: H04L 9/0866 involving user or device identifiers, e.g. serial number, physical or biometrical information, DNA, hand-signature or measurable physical characteristics
• CPC Class Codes: H04L 9/0897 involving additional devices, e.g. trusted platform module [TPM], smartcard or USB

Abstract

A device, including one or more Communication Physical Unclonable Function (CPUF) and key storage devices, the CPUF devices each including: a coherent Electromagnetic (EM) radiation source; a spatial light modulator (SLM) connected to the coherent EM radiation source; a volumetric scattering medium connected to the SLM; a detector connected to the volumetric scattering medium; and one or more processors or circuits connected to the detector and one or more processors or circuits connected to the SLM. A communication protocol is also provided.

Claims

1. A device, comprising one or more Communication Physical Unclonable Function (CPUF) devices, the CPUF devices capable of key storage and the CPUF devices each comprising:

a coherent Electromagnetic (EM) radiation source;

a spatial light modulator (SLM) connected to the coherent EM radiation source, wherein;

the SLM comprises pixels and is positioned to receive, on the pixels, coherent Electromagnetic (EM) radiation from the coherent EM radiation source; and

upon receipt of the coherent EM radiation, the pixels shape or modify a phase and/or an amplitude of the coherent EM radiation according to one or more patterns or a sequence of patterns, to form and transmit patterned EM radiation having a patterned phase and a patterned amplitude;

a volumetric scattering medium connected to the SLM, wherein;

the volumetric scattering medium is positioned to receive and scatter the patterned EM radiation into keyed EM radiation; and

upon receipt of the patterned EM radiation, the volumetric scattering medium shapes or modifies the patterned phase and the patterned amplitude of the patterned EM radiation into a keyed phase and a keyed amplitude of keyed EM radiation;

a detector connected to the volumetric scattering medium, the detector positioned to detect an output speckle of the keyed EM radiation and comprising a circuit that produces a digital signal in response to the keyed EM radiation; and

one or more processors or one or more circuits connected to the detector and one or more processors or one or more circuits connected to the SLM, wherein one or more of the processors or one or more of the circuits randomize the digital signal to transform the output speckle into a digital key used to encrypt a message.

2. The device of claim 1, wherein the SLM, the volumetric scattering medium, and the detector are in a package or integrated circuit, and connected with stability such that a communication key stored in the CPUF device is at least 50% reproducible, or at least 50% of bits in the key are the same, at least 24 hours after formation of the key in the CPUF device.

3. The device of claim 1, wherein:

the volumetric scattering medium is attached to the detector via a first refractive medium;

the SLM is physically attached to the volmetric scattering medium and sensor via a second refractive medium; and

all control electronics for the CPUF device are embedded within the volumetric scattering medium.

4. The device of claim 1, further comprising a refractive medium and distance between the SLM and the detector, wherein an overlap between the SLM'"'"'s pixels and the detector'"'"'s pixels is maximized.

5. The device of claim 1, further comprising a refractive medium that produces a tailored focus of the patterned EM radiation on the volumetric scattering medium.

6. The device of claim 1, wherein the one or more processors or the one or more circuits connected to the SLM generate, control, and input the one or more patterns on the SLM to obtain one or more keys.

7. The device of claim 1, wherein each of the pixels represents a one or a zero of one of the patterns, and the one of the patterns comprises random half ones and half zeros.

8. The device of claim 1, further comprising a distance between the volumetric scattering medium and the detector that matches a speckle size of the keyed EM radiation with the detector'"'"'s pixels.

9. The device of claim 1, wherein the volumetric scattering medium comprises a material that does not decorrelate over time or is stable over at least 24 hours.

10. The device of claim 1, wherein the volumetric scattering medium is an opal coated scatterer.

11. The device of claim 1, further comprising an apodizing or aperture mask on the volumetric scattering medium between the volumetric scattering medium and the detector, wherein the mask shapes the output speckle.

12. The device of claim 1, wherein the one or more processors or the one or more circuits connected to the detector include one or more error correction processors or error correction circuits that perform error correction of the key stored in the CPUF device.

13. A system comprising the CPUF devices of claim 1 for securely communicating between a first party and a second party, further comprising:

a first one of the CPUF devices;

a second one of the CPUF devices; and

computers including a first computer and a second computer;

wherein the CPUF devices and the computers perform one or more of the following functions;

(1) producing one or more first keys, in the first CPUF device at one or more first locations, in response to the one or more patterns;

(2) producing one or more second keys, in the second CPUF device at the one or more first locations, in response to the one or more patterns,

(3) producing or generating in one or more of the computers at the one or more first locations, one or more functions wherein each function is a function of one of the first keys and one of the second keys generated by the same pattern;

(4) storing in one or more databases on one or more of the computers, the patterns, the functions, and an association between the functions and the patterns;

(3) re-creating or reproducing one of the first keys, in the first CPUF device at a second location, using one of the patterns, to form a re-created or reproduced first key;

(4) encrypting, in the first computer at the second location, a message with the re-created or reproduced first key, forming an encrypted message;

(5) sending or transmitting, from the first computer at the second location, the encrypted message and the one of the patterns;

(6) receiving, in the second computer at a third location, the encrypted message and the one of the patterns;

(7) re-creating or reproducing in the second CPUF device at the third location, one of the second keys using the one of the patterns, to form a re-created or reproduced second key;

(8) obtaining, from the databases, the function corresponding to the one of the patterns;

(9) operating, in the second computer at the third location, on the encrypted message using the re-created or the reproduced second key and the function, thereby decrypting the message; and

wherein;

the first location comprises a physical location or locations where the first party and the second party have met or established a secure connection, and

the second location and the third location are physical locations of the first party and the second party, respectively, at a later time and after the first party and the second party have separated.

14. The system of claim 13, wherein:

the function is an XOR operation between the first key and the second key;

the encryption is an XOR operation between the message M expressed in binary and the binarized first key b_i, producing the encrypted message M⊕

b_i; and

the operating is a double XOR procedure of the encrypted message (b_i⊕

M)⊕

(b_i⊕

a_i)⊕

a_i=M, wherein a_i is the reproduced second key and such that an output of the XOR process is the original message M.

15. The system of claim 13, wherein the first computer concatenates a plurality of the first keys to encrypt a message that is longer than each of the first keys.

16. A system comprising the CPUF devices of claim 1 for communicating between a first party and a second party, further comprising:

(a) a first one of the CPUF devices that creates, stores, and re-creates or reproduces one or more first keys upon receipt of one or more first patterns;

(b) a second one of the CPUF devices that creates, stores, and re-creates or reproduces one or more second keys upon receipt of one or more second patterns;

(c) one or more computers that;

encrypt a message using one of the re-created or reproduced keys, wherein the re-created or reproduced key has 0% error as compared to the created key; and

use a public key protocol to establish a secure connection between the CPUFs and transmit or receive the encrypted message.

17. The device of claim 1, wherein the one or more processors or circuits connected to the detector perform a whitening algorithm, comprising:

transforming data comprising the output speckle, detected by the detector, into a column vector; and

multiplying the column vector with a rectangular binary sparse random matrix, thereby producing the digital key comprising a whitened key.

18. The device of claim 17, wherein the whitening algorithm, the SLM'"'"'s pixels, and stability of the CPUF device, are such that the CPUF device generates, stores, and extracts a key with more than 10000 random bits.

19. A method of encrypting and/or decrypting, comprising:

(a) obtaining or providing a first device and a second device, the first and second devices each comprising;

a volumetric scattering medium connected to a source of patterned Electromagnetic (EM) radiation;

a detector connected to the volumetric scattering medium; and

one or more processors and/or one or more circuits connected to the detector;

(b) providing a first party with the first device and a second party with second device; and

(c) providing a protocol, the protocol comprising;

(i) establishing a secure connection or meeting between the first party and the second party;

(ii) inputting or showing a same pattern or same sequence of patterns on each of the devices;

(iii) recording one or more first keys in the first device and one or more second keys in the second device using the one or more patterns; and

(iv) generating one or more key functions wherein each key function is a function of one of the first keys and one of the second keys generated by the same pattern, to form one or more key functions.

20. The method of claim 19, further comprising:

(iv) digitally saving the one or more patterns and the one or more key functions as one or more entries in a database, wherein each database entry comprises one of the key functions and the the pattern used to form the first key and the second key associated with the one of the key functions;

(v) the first party selecting one of the patterns and using the first device to recreate or reproduce the first key associated with the one or more patterns, to form a reproduced first key;

(vi) encrypting a message with the reproduced first key;

(vii) the first party sending the encrypted message and the one of the patterns used to obtain the reproduced first key;

(viii) the second party receiving the encrypted message and the one of the patterns;

(ix) the second party decrypting the encrypted message by

(1) using the one of the patterns to generate or reproduce the second key with the second device, to form a reproduced second key;

(2) obtaining the key function associated with the one or more patterns from the entry in the database corresponding to the one of the patterns, and

(3) operating on the encrypted message with the key function associated with one of the patterns and the second key.

21. A method of encrypting and/or decrypting, comprising:

(a) providing or obtaining two devices, the devices each comprising;

a source of patterned Electromagnetic (EM) radiation, the patterned EM radiation having a patterned phase and/or a patterned amplitude according to one or more patterns inputted to the source of patterned EM radiation;

a volumetric scattering medium connected to the source of patterned EM radiation, wherein;

the volumetric scattering medium is positioned to receive and scatter the patterned EM radiation into keyed EM radiation; and

upon receipt of the patterned EM radiation, the volumetric scattering medium modifies the patterned phase and the patterned amplitude of the patterned EM radiation to form the keyed EM radiation;

a detector connected to the volumetric scattering medium, the detector positioned to detect an output speckle of the keyed EM radiation and comprising a circuit that produces a digital signal in response to the keyed EM radiation; and

one or more processors and/or circuitry connected to the detector, for randomizing the digital signal to transform the output speckle into a digital key used to encrypt and/or decrypt;

providing a first party and a second party each with one of the devices; and

providing a protocol, the protocol comprising;

(i) creating and storing a first party key comprising the digital key obtained using the first party'"'"'s device;

(ii) creating and storing a second party key comprising the digital key obtained using the second party'"'"'s device;

(iii) using a public key protocol to establish a secure connection between the first party and the second party;

(iv) re-creating or reproducing the first party key using the first party'"'"'s device to form a reproduced first party key and/or re-creating or reproducing the second party key using the second party'"'"'s device to form a reproduced second party key, whenever is required by the public key protocol, wherein;

the reproduced first party key has 0% error as compared to the first party key, and/or

the reproduced second party key has 0% error as compared to the second party key.

22. One or more devices, the devices each comprising:

a source of patterned Electromagnetic (EM) radiation, the patterned EM radiation having a patterned phase and/or a patterned amplitude in response to, and according to, one or more patterns inputted to the source of patterned EM radiation;

a volumetric scattering medium connected to the source of patterned EM radiation, wherein;

the volumetric scattering medium is positioned to receive and scatter the patterned EM radiation into keyed EM radiation, and

the volumetric scattering medium can modify the patterned phase and/or the patterned amplitude of the patterned EM radiation to form the keyed EM radiation;

a detector connected to the volumetric scattering medium, the detector positioned to detect an output speckle of the keyed EM radiation and comprising circuitry that produces a digital signal in response to the keyed EM radiation; and

one or more processors connected to the detector, wherein the one or more processors can randomize the digital signal to transform the output speckle into a digital key used to encrypt and/or decrypt.

23. The one or more devices of claim 22, wherein the source of patterned EM radiation comprises pixels and/or a spatial light modulator (SLM) positioned to receive EM radiation from an EM radiation source, wherein the SLM and/or the pixels modify a phase and/or an amplitude of the EM radiation according to the one or more patterns to form the patterned EM radiation having the patterned phase and/or the patterned amplitude.

24. A system comprising the devices of claim 22, further comprising:

two of the devices, comprising a first device and a second device, wherein one or more first keys are produced in the first device and one or more second keys are produced in the second device, using the one or more patterns; and

a computer connected to the devices and that can produce one or more key functions, wherein each key function is a function of one of the first keys and one of the second keys produced by the same pattern.

25. A method of fabricating a device, comprising:

positioning a volumetric scattering medium to receive patterned EM radiation from a source of patterned Electromagnetic (EM) radiation, wherein;

the patterned EM radiation has a patterned phase and/or patterned amplitude according to, and in response to, one or more patterns inputted to the source of patterned EM radiation,

the volumetric scattering medium is positioned to receive and scatter the patterned EM radiation into keyed EM radiation, and

the volumetric scattering medium can modify the patterned phase and/or the patterned amplitude of the patterned EM radiation to form the keyed EM radiation;

positioning a detector to detect an output speckle of the keyed EM radiation, the detector comprising circuitry that produces a digital signal in response to the keyed EM radiation; and

connecting one or more processors to the detector, wherein the one or more processors can randomize the digital signal to transform the output speckle into a digital key used to encrypt and/or decrypt.