IP Library › Granted Patent US 12,640,936
Granted Patent B2
US 12,640,936 · App. 17/532,809 · Granted May 26, 2026

Cryptographic methods and systems using blinded activation codes for digital certificate revocation

Inventors: Marcos A. Simplicio (São Paulo, BR); Eduardo Lopes Cominetti (São Paulo, BR); Harsh Kupwade Patil (Fremont, CA); Jefferson E. Ricardini (São Paulo, BR); Marcos Vinicius M. Silva (São Paulo, BR)
Assignees: LG ELECTRONICS, INC.; UNIVERSITY OF SAO PAULO
H04L9/3268H04L9/0894H04L9/321H04L2209/42H04L2209/84
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Quick Facts
Patent No.
US 12,640,936
App. No.
17/532,809
Granted
May 26, 2026
Kind
B2
Abstract

To revoke a digital certificate ( 160 p ), activation of the digital certificate is blocked by withholding an activation code from the certificate user ( 110 ). The certificates are generated by a plurality of entities ( 210, 220, 838 ) in a robust process that preserves user privacy (e.g. anonymity) even in case of collusion of some of the entities. The process is suitable for connected vehicles, e.g. as an improvement for Security Credential Management System (SCMS).

Claims (32)

1 . A method by a registration authority (RA) operating in a security credential management system, the method comprising:

receiving by the RA a certificate request from an end entity, the certificate request requesting a certificate;

transmitting by the RA a request for a blinded activation value to a certificate access manager (CAM), the blinded activation value request containing identification information for the associated end entity;

obtaining by the RA from the CAM a blinded activation value, wherein the blinded activation value is an elliptic curve point generated by multiplication of an activation code by a generating point G, the blinded activation value for use in encrypting the certificate to be provided to the end entity, wherein the blinded activation value is added to a cocoon public key to modify the cocoon public key;

shuffling by the RA the certificate request with other certificate requests from other end entities;

transmitting by the RA to a certificate authority (CA) the cocoon public key modified with the addition of the blinded activation value;

wherein the CA generates a response structure comprising the certificate, wherein the certificate is encrypted using the blinded activation value obtained from the CAM and cannot be accessed by the end entity until provided with the activation code from the CAM;

wherein the RA does not know the certificate sent to the end entity because the certificate is encrypted, wherein the CA is not able to determine the end entity to which the certificate belongs.

2 . The method of claim 1 , wherein the activation code depends on an interval of time for which the certificate is to be activated.

3 . The method of claim 1 , comprising generating by the RA at least one cocoon key using the blinded activation value.

4 . The method of claim 1 wherein the activation code is calculated using a binary hash tree structure comprising a plurality of nodes.

5 . The method of claim 4 wherein at least one node of the binary hash tree structure corresponds to the end entity.

6 . The method of claim 1 wherein the certificate comprises an authorization certificate.

7 . The method of claim 1 wherein the certificate comprises a pseudonym certificate.

8 . The method of claim 1 wherein the (CA) comprises a pseudonym certificate authority (PCA).

9 . The method of claim 1 wherein the blinded activation value comprises a blinded activation code.

10 . A computer system comprising one or more hardware processors and non-transitory computer storage, the computer system being programmed to perform as a registration authority (RA) operating in a security credential management system, the RA being programmed to:

receive a certificate request from an end entity, the certificate request requesting a certificate;

transmit a request for a blinded activation value to a certificate access manager (CAM), the blinded activation value request containing identification information for the associated end entity;

obtain from the CAM a blinded activation value, wherein the blinded activation value is an elliptic curve point generated by multiplication of an activation code by a generating point G, the blinded activation value for use in encrypting the certificate to be provided to the end entity, wherein the blinded activation value is added to a cocoon public key to modify the cocoon public key;

shuffle the certificate request with other certificate requests from other end entities;

transmit to a certificate authority (CA) the cocoon public key modified with the addition of the blinded activation value;

wherein the CA generates a response structure comprising the certificate, wherein the certificate is encrypted using the blinded activation value obtained from the CAM and cannot be accessed by the end entity until provided with the activation code from the CAM;

wherein the RA does not know the certificate sent to the end entity because the certificate is encrypted, wherein the CA is not able to determine the end entity to which the certificate belongs.

11 . The system of claim 10 , wherein the activation code depends on an interval of time for which the certificate is to be activated.

12 . The system of claim 10 , wherein the RA is further programmed to generate at least one cocoon key using the blinded activation value.

13 . The system of claim 10 wherein the activation code is calculated using a binary hash tree structure comprising a plurality of nodes.

14 . The system of claim 13 wherein at least one node of the binary hash tree structure corresponds to the end entity.

15 . The system of claim 10 wherein the certificate comprises an authorization certificate.

16 . The system of claim 10 wherein the certificate comprises a pseudonym certificate.

17 . The system of claim 10 wherein the (CA) comprises a pseudonym certificate authority (PCA).

18 . The system of claim 10 wherein the blinded activation value comprises a blinded activation code.

Continuity (3)
Continuation 16267741 · Feb 5, 2019
Provisional Application 62626672 · Feb 5, 2018
Related Publication 20220158854A1 · May 19, 2022
References Cited (138)
US 5432852A · Leighton et al. · 1995 [cited by applicant]
US 6487658B1 · Micali · 2002 [cited by applicant]
US 6976162B1 · Ellison · 2005 [cited by examiner]
US 8281149B2 · Laurie · 2012 [cited by examiner]
US 8732457B2 · Micali · 2014 [cited by applicant]
US 9094206B2 · Di Crescenzo et al. · 2015 [cited by applicant]
US 9425967B2 · Tseng et al. · 2016 [cited by applicant]
US 9584320B1 · Parkinson · 2017 [cited by examiner]
US 10439825B1 · Meyer et al. · 2019 [cited by applicant]
US 11184180B2 · Simplicio, Jr. · 2021 [cited by examiner]
US 11190363B2 · Simplicio, Jr. · 2021 [cited by examiner]
US 20030009612A1 · Latta · 2003 [cited by applicant]
US 20030115468A1 · Aull · 2003 [cited by examiner]
US 20050114653A1 · Sudia · 2005 [cited by examiner]
US 20050154878A1 · Engberg et al. · 2005 [cited by applicant]
US 20050222932A1 · Murashita · 2005 [cited by examiner]
US 20060137006A1 · Ramzan et al. · 2006 [cited by applicant]
US 20070116271A1 · Kurdziel · 2007 [cited by applicant]
US 20070222555A1 · Tengler et al. · 2007 [cited by applicant]
US 20070244833A1 · Camenisch · 2007 [cited by examiner]
US 20080052772A1 · Conrado et al. · 2008 [cited by applicant]
US 20080189774A1 · Ansari et al. · 2008 [cited by applicant]
US 20080211624A1 · Micali et al. · 2008 [cited by applicant]
US 20080232595A1 · Pietrowicz · 2008 [cited by examiner]
US 20080301447A1 · Hughes · 2008 [cited by examiner]
US 20090259841A1 · Laberteaux et al. · 2009 [cited by applicant]
US 20090262930A1 · Lambert · 2009 [cited by examiner]
US 20090298576A1 · Nguyen · 2009 [cited by applicant]
US 20100111307A1 · Hu et al. · 2010 [cited by applicant]
US 20100205457A1 · Jogand-Coulomb et al. · 2010 [cited by applicant]
US 20100317420A1 · Hoffberg · 2010 [cited by applicant]
US 20110055556A1 · Choi et al. · 2011 [cited by applicant]
US 20110191581A1 · Shim et al. · 2011 [cited by applicant]
US 20110258435A1 · Bellur et al. · 2011 [cited by applicant]
US 20120070000A1 · Baechler et al. · 2012 [cited by applicant]
US 20120072718A1 · Ronda et al. · 2012 [cited by applicant]
US 20120072723A1 · Orsini et al. · 2012 [cited by applicant]
US 20120079602A1 · Kolesnikov et al. · 2012 [cited by applicant]
US 20120102318A1 · Vanstone · 2012 [cited by applicant]
US 20120173873A1 · Bell · 2012 [cited by examiner]
US 20120204032A1 · Wilkins et al. · 2012 [cited by applicant]
US 20120233705A1 · Boysen · 2012 [cited by examiner]
US 20130159702A1 · Peeters · 2013 [cited by examiner]
US 20130227297A1 · Gantman et al. · 2013 [cited by applicant]
US 20140025950A1 · Peeters et al. · 2014 [cited by applicant]
US 20140059348A1 · Ronda et al. · 2014 [cited by applicant]
US 20140093077A1 · Jawurek et al. · 2014 [cited by applicant]
US 20150222604A1 · Ylonen · 2015 [cited by applicant]
US 20150256348A1 · Tschache · 2015 [cited by applicant]
US 20160119151A1 · Park · 2016 [cited by examiner]
US 20160218875A1 · Le Saint · 2016 [cited by examiner]
US 20170180989A1 · Etzel et al. · 2017 [cited by applicant]
US 20170222990A1 · Romansky et al. · 2017 [cited by applicant]
US 20170244676A1 · Edwards · 2017 [cited by examiner]
US 20170346633A1 · Bos · 2017 [cited by examiner]
US 20180006829A1 · Kravitz et al. · 2018 [cited by applicant]
US 20180137261A1 · Lattin et al. · 2018 [cited by applicant]
US 20180219678A1 · Medvinsky et al. · 2018 [cited by applicant]
US 20180316511A1 · Meyer et al. · 2018 [cited by applicant]
US 20190020629A1 · Baird, III · 2019 [cited by examiner]
US 20190109711A1 · Gladwin · 2019 [cited by examiner]
US 20190116048A1 · Chen et al. · 2019 [cited by applicant]
US 20190123915A1 · Simplicio, Jr. et al. · 2019 [cited by applicant]
US 20190215165A1 · Simplicio, Jr. et al. · 2019 [cited by applicant]
US 20190238342A1 · Lian et al. · 2019 [cited by applicant]
US 20190245703A1 · Simplicio Junior, Jr. et al. · 2019 [cited by applicant]
US 20190245831A1 · Petit et al. · 2019 [cited by applicant]
US 20190392120A1 · Lattin et al. · 2019 [cited by applicant]
CN 102301643B · 2014 [cited by applicant]
CN 104901931B · 2018 [cited by applicant]
JP 2004206435A · 2004 [cited by applicant]
Lawrence et al., “Security credentials Management system (SCMS) design and analysis for the connected vehicle system: draft.” National Transportation Library, Dec. 27, 2013 [retrieved on Jan. 24, 2026]. Retrieved from t… [cited by examiner]
NISTp256 “Recommended Elliptic Curves for Federal Government Use,” National Institute of Standards and Technology_Available at: http://csrc.nisl.gov/groups/ST/loolkil/documents/dss/NISTReCur.doc. Jul. 1999. pp. 1-43. [cited by applicant]
Paillier, “Public-Key Cryptosystems Based on Composite Degree Residuosity Classes,” Advances in Cryptology—Eurocrypt'99. Springer-Verlag. Berlin, Heidelberg. 1999. pp. 223-238. [cited by applicant]
P. Papadimitratos et al., Vehicular Communication Systems: Enabling Technologies, Applications, and Future Outlook on Intelligent Transportation, IEEE Communications Magazine, vol. 47, No. 11. Nov. 2009. pp. 84-95. [cited by applicant]
C. Perera et al., “Context Aware Computing for the Internet of Things: A survey,” IEEE Communications Surveys lrutorials, vol. 16, No. 1. Winter 2014. pp. 414-454. [cited by applicant]
J. Petit et al., “Pseudonym Schemes in Vehicular Networks: A survey,” Articles in IEEE Communications Surveys lrutorials, vol. 17, No. 1. Aug. 15, 2015. pp. 228-255. [cited by applicant]
B. Preneel et al., “Data Encryption Standard (DES),” Boston, Mass.: Springer US. 2005. pp. 136-136. [cited by applicant]
M. Raya et al., “Eviction of Misbehaving and Faulty Nodes in Vehicular Networks,” IEEE Journal on Selected Areas in Communications, vol. 25, No. 8. Oct. 2007. pp. 1-12. [cited by applicant]
F. Schaub et al., “Privacy Requirements in Vehicular Communication Systems,” in Proceedings of the International Conference on Computational Science and Engineering, vol. 3. IEEE, 2009, pp. 139-145. [cited by applicant]
M. Simplicio et al., “A Privacy-Preserving Method for Temporarily Linking/Revoking Pseudonym Certificates in Vehicular Networks,” 17th IEEE International Conference on Trust, Security and Privacy In Computing and Commun… [cited by applicant]
M. Simplicio et al., “The Unified Butterfly Effect: Efficient Security Credential Management System for Vehicular Communications,” International Association of Cancer Registries (IACR). Available at: https:I/eprint.iacr… [cited by applicant]
E. Verheul, “Activate Later Certificates for V2X.—Combining ITS Efficiency With Privacy,” Cryptology ePrint Archive, Report 2016/1158, 2016. Available at: http:/leprint.iacr.org/2016/1158, Dec. 22, 2016. pp. 1-28. [cited by applicant]
NIST, Special Publication 800-131A Rev. 1—“Transitions: Recommendation for Transitioning the Use of Cryptographic Algorithms and Key Lengths,” National Institute of Standards and Technology, U.S. Department of Commerce,… [cited by applicant]
International Search Report by the International Searching Authority for PCT Application No. PCT/US2019/016658, May 14, 2019, pp. 1-8. [cited by applicant]
Written Opinion issued of the International Searching Authority for PCT Application No. PCT/US2019/016658, May 14, 2019, pp. 1-6. [cited by applicant]
Simplicio Jr. et al., “ACPC: Efficient revocation of pseudonym certificates using activation codes”, Published by t:: Isevier B.V., Ad Hoc Networks, 2018, p. 1-23. [cited by applicant]
Virendra Kumar et al., “Binary Hash Tree based Certificate Access Management for Connected Vehicles”, WiSec 17: Proceedings of the 10th ACM Conference on Security and Privacy in Wireless and Mobile, USA, Sep. 18, 2017, … [cited by applicant]
William Whyte et al., “A Security Credential Management System for V2V Communications”, 2013 IEEE Vehicular Networking Conference, U.S.A., IEEE, 2013-12-16, p. 1-8. [cited by applicant]
Verheul, “Issue First Activate Later Certificates for V2X—Combining ITS efficiency with privacy”, IACR International Association for Cryptologic Research, vol. 20161222:090905, Dec. 18, 2016,Dec. 18, 2016), pp. 1-28. [cited by applicant]
European Patent Office, “Extended European Search Report”, dated Aug. 13, 2021, 11 pages. [cited by applicant]
Yipin Sun et al., “NEHCM: A Novel and Efficient Hash-chain based Certificate Management Scheme for Vehicular Communications” 2010 5th International ICST Conference on Communications and Networking in China. (Year: 2010)… [cited by applicant]
Domain Control Validation (DCV) for SSL Certificate Naija Domains, Jan. 13, 2017; [retrieved on Apr. 7, 2021]. From the Internet: <URL: https://web.archive.org/web/20170113211014/ https://help.naijadomains.com/ can-comp… [cited by applicant]
Jin Wang et al., “RP Rep: A Robust and Privacy-Preserving Reputation management Scheme for Pseudonym-Enabled VANETs” International Journal of Distributed Sensor Networks, vol. 2016, Article ID 6138251. (Year: 2016). [cited by applicant]
International Search Report and Written Opinion issued by the International Searching Authority on Apr. 22, 2019 for PCT Application No. PCT/US2019/013084. pp. 1-16. [cited by applicant]
U.S. Appl. No. 62/561,667, filed Sep. 21, 2017. [cited by applicant]
U.S. Appl. No. 16/136,621, filed Sep. 20, 2018. [cited by applicant]
U.S. Appl. No. 16/165,871, filed Oct. 19, 2018. [cited by applicant]
PCT Patent Application No. PCT/US2018/056784, filed Oct. 19, 2018. [cited by applicant]
W. Aiello et al., “Fast Digital Identity Revocation (extended abstract),” in Proc. of the 18th Annual International ryptology Conference on Advances in Cryptology (CRYPTO'98). London, UK Springer-Verlag, 1998 pp. 137-15… [cited by applicant]
International Search Report and Written Opinion issued by the International Searching Authority on Feb. 7, 2019 or PCT Application No. PCT/US2018/056784. pp. 1-17. [cited by applicant]
Zheng et al., “Digital Signcryption or How to Achieve Cost (Signature & Encryption) Cost (Signature)+ Cost Encryption),” Advances in Cryptology—CRYPTO '97: 17th Annual International Cryptology Conference. Berlin, Heidel… [cited by applicant]
K. Alheeti et al., “An Intrusion Detection System Against Malicious Attacks on the Communication Network of Driverless cars,” in 12th Annual IEEE Consumer Communications and Networking Conference (CCNC), Jan. 2015, pp. … [cited by applicant]
E. Andrade et al., “Lyra2: Efficient Password Hashing with High Security Against Time-Memory Trade-Offs,” IEEE Transactions on Computers, vol. 65, No. 10. Sao Paulo, Brazil, 2016 pp. 3096-3108. see also: http://eprinl.i… [cited by applicant]
D. Bernstein et al., “EdDSA for More Curves,” Journal of Cryptographic Engineering, vol. 2, No. 2. Jul. 4, 2015. Available at: http://ed25519.cr.yp.to/eddsa-20150704.pdf. pp. 1-5. [cited by applicant]
D. Bernstein et al., “High-Speed High-Security Signatures”, In Cryptographic Hardware and Embedded Systems—:; HES 2011. Berlin, Heidelberg, 2011, Springer Berlin Heidelberg. Oct. 5, 2011. pp. 124-142. [cited by applicant]
E. Biham et al., “How to Decrypt or Even Substitute DES—Encrypted Messages in 228 Steps,” Information Processing cellers, vol. 84, No. 3. Mar. 1, 2002. pp. 117-124. [cited by applicant]
D. Brown et al., “Provably Secure Implicit Certificate Scheme,” Financial Cryptography, pp. 156-165, Berlin, Heidelberg, 2002. Springer-Verlag. pp. 1-10. [cited by applicant]
CAMP LLC, “Security Credential Management System Proof-of-Concept Implementation—EE Requirements and Specifications Supporting SCMS Software Release 1.1,” Vehicle Safety Communications Consortium, Tech. Rep., May 4, 201… [cited by applicant]
Certicom Research, “Sec 4: Elliptic Curve Ou-Vanstone Implicit Certificate Scheme (ECQV),” Certicom Research. Standards for Efficient Cryptography. Jan. 24, 2013, http://www.secg.org/sec4-1.0.pdf. pp. 1-32. [cited by applicant]
S. Chen et al., Vehicle-to-Everything (v2x) Services Supported by L TE-Based Systems and 5G, IEEE Communications Standards Magazine, vol. 1, No. 2. Jun. 2017. pp. 70-76. [cited by applicant]
P. Cincilla et al., Vehicular PKI Scalability-Consistency Trade-Offs in Large Scale Distributed Scenarios, in IEEE Vehicular Networking Conference (VNC), Dec. 2016, pp. 1-8. [cited by applicant]
D. Cooper et al., “RFC 5280—Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List CRL) proflle,” RFC 5280—hllps://lools.ielf.org/hlml/rfc5280#section-4.2.1.3, May 2008. pp. 1-151. [cited by applicant]
J. Coron et al., “Universal Padding Schemes for RSA,” Advances in Cryptology (CRYPTO'02), London, UK, 2002. Springer. pp. 226-241. [cited by applicant]
J. Douceur, “The Sybil attack,” in Proc. of 1st International Workshop on Peer-to-Peer Systems (IPTPS). Microsoft Research. Springer, Jan. 2002. Available at: hllps://www.microsofl.com/en-us/research/publication/lhe-syb… [cited by applicant]
ETSI, “TR 102 941—Intelligent Transport Systems (ITS); Security; Trust and Privacy Management,” European Telecommunications Standards Institute, Tech. Rep., Jun. 2012. pp. 1-30. [cited by applicant]
Federal Information Processing Standard (FIPS 186-4)—Digital Signature Standard (DSS), National Institute of Standards and Technology, U.S. Department of Commerce. Jul. 2013. pp. 1-130. [cited by applicant]
D. Forster et al., “PUCA: A Pseudonym Scheme with Strong Privacy Guarantees for Vehicular Ad-hoc Networks,” Ad Hoc Networks, vol. 37. Special Issue on Advances in Vehicular Networks. 2015. pp. 1-11. [cited by applicant]
Gemalto, “SafeNet Luna Network HSM” SafeNet Identity & Data Protection Solutions from Gemalto—product brief Available at: hllps://safenel.gemalto.com/. Nov. 18, 2018. pp. 1-7. [cited by applicant]
J. Haas et al., “Design and Analysis of a Lightweight Certificate Revocation Mechanism for Vane!,” in Proceedings of he Sixth ACM International Workshop on Vehicular Internet Working. ACM. Sep. 25, 2009, pp. pp. 1-10. [cited by applicant]
J. Harding et al., “Vehicle-to-Vehicle Communications: Readiness of V2V Technology for Application,” National Highway Traffic Safety Administration. Washington, DC, USA, Tech. Rep. DOT HS 812 014. Aug. 2014. pp. 1-327. [cited by applicant]
IEEE, “IEEE Standard for Wireless Access in Vehicular Environments—Security Services for Applications and Management Messages—Amendment 1,” IEEE Sid 1609.2a-2017 {Amendment to IEEE Sid 1609.2-2016), Sep. J8, 2017. pp. 1… [cited by applicant]
IEEE, “IEEE Standard Specifications for Public-Key Cryptography—Amendment 1: Additional Techniques,” IEEE :; omputer Society. Sep. 2, 2004. pp. 1-168. [cited by applicant]
A.Iyer et al., “Secure V2V Communications: Performance Impact of Computational Overheads,” Proceedings of the EEE INFOCOM Workshops. Apr. 2008. pp. 1-8. [cited by applicant]
D. Jiang et al., “IEEE 802.11 p: Towards an International Standard for Wireless Access in Vehicular Environments,” in EEE Vehicular Technology Conference (VTC Spring). May 2008. pp. 2036-2040. [cited by applicant]
S. Josefsson et al., “Edwards-Curve Digital Signature Algorithm,” {EdDSA) Available at: hllps://lools.ielf.org/hlml/rfc8032. Jan. 2017. pp. 1-60. [cited by applicant]
M. Khodaei et al., “The Key to Intelligent Transportation: Identity and Credential Management in Vehicular Communication Systems,” IEEE Vehicular Technology Magazine, vol. 10, No. 4. Dec. 2015. pp. 63-69. [cited by applicant]
L. Lamport, “Password Authentication With Insecure Communication,” Commun. ACM, National Science roundalion, vol. 24, No. 11. Menlo Park, CA. 1901. pp. 770-772. [cited by applicant]
K. Lauter et al., “The Elliptic Curve Discrete Logarithm Problem and Equivalent Hard Problems for Elliptic Divisibility Sequences,” Selected Areas in Cryptography {SAC'08), Springer, 2008. pp. 309-327. [cited by applicant]
D.McGrew et al., “Hash-Based Signatures,” Internet Engineering Task Force, Internet-Draft Draft-Mcgrew-Hash-Sigs-06. Available at: https://dalatracker.ielf.org/doc/hlml/drafl-mcgrew-hash-sigs-06. Sep. 6, 2017. pp. 1-51. [cited by applicant]
R. Moalla et al., “Risk Analysis Study of ITS Communication Architecture.” in 3rd International Conference on The Network of the Future. Paris, France. 2012. pp. 1-5. [cited by applicant]
N. Mouha et al., “Multi-Key Security: The Even-Mansour Construction Revisited,” in Advances in Cryptology CRYPTO 2015: 35th Annual Cryptology Conference. Berlin, Heidelberg: Springer Berlin Heidelberg. Aug. 16-20, 2015.… [cited by applicant]
NHTSA, “Federal Motor Vehicle Safety Standards; V2V Communication,” National Highway Traffic Safety Administration, U.S. Department of Transportation (USDOT), Tech. Rep. Available at: hllps://www.federalregister.gov/ :d… [cited by applicant]
NIST, “Secure Hash Standard (SHS),” Federal Information Processing Standard (FIPS 180-4). National Institute of Standards and Technology, U S. Department of Commerce. (NIST), Gaithersburg, MD, USA. DOI:10.6028/NIST. FIP… [cited by applicant]
NIST, Federal Information Processing Standard (FIPS 197)—“Advanced Encryption Standard (AES),” National nstitute of Standards and Technology, U.S. Department of Commerce. Gaithersburg, MD, USA. Available at: http:// ::s… [cited by applicant]
NIST, Federal Information Processing Standard (FIPS 202)—SHA-3 Standard, “Permutation-Based Hash and Extendable-Output Functions,” National Institute of Standards and Technology, U.S. Department of Commerce. Gaithersbur… [cited by applicant]
European Patent Office, “Extended European Search Report”, Application No. 19747989.2, dated Nov. 9, 2021, 10 pages. [cited by applicant]
Office Action for corresponding Chinese Patent Application No. 201980011608.5 dated Nov. 17, 2022, 17 pages. [cited by applicant]