DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This Office Action is in response to the application 19/052442 filed on 02/13/2025.
Claims 1-15 have been examined and are pending in this application.
Priority
Applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d) to Korean Patent Application No. 10-2024-0020430, filed on February 13, 2024, and Korean Patent Application No. 10-2025-0008424, filed on January 21, 2025, is acknowledged.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-15 are rejected under 35 U.S.C. 103 as being unpatentable over Drucker et al. (“Drucker,” US 2024/0405973) in view of Gentry et al. (“Gentry,” US 2016/0164670).
Regarding claim 1: Drucker discloses an electronic apparatus comprising:
a communication device (Drucker: fig. 1);
a memory storing a first secret key and a first public key corresponding to the first secret key, and storing at least one instruction (Drucker: fig. 1 item 124 storage; par. 0032 generates a principle set of keys (secret key "sk1," public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1"); par. 0034 the keys may also be stored locally); and
a processor (Drucker: fig. 1 item 120 processing circuitry) configured to execute the at least one instruction,
wherein the processor is configured to generate a switching key based on a second public key and the first secret key if the processor receives the second public key from a terminal device corresponding to a first user (Drucker: par. 0033 uploads (public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1") to HEkeygen_cloud; par. 0034 generates an ephemeral set of keys K (secret key "sk," public key "pk," evaluation key "evaluation1, "skA=switchKey_ { sk-sk1,}, skB=switchKey_ { sk1-sk} )), and
control the communication device to transmit the first public key to the terminal device (Drucker: par. 0063 Org 320 may then transmit the HE public key 326pk, the HE evaluation key 326e, and the plurality of HE rotation keys 326r for the principal instance 350),
the switching key being a key that enables a homomorphic ciphertext encrypted using the first public key to be decrypted using a second secret key corresponding to the second public key (Drucker: par. 0058 the HE processor 204 may then encrypt the prepared encrypted input data 224 using a homomorphic encryption public key 226pk to generate a set of encrypted input data 224; par. 0018 decrypt a ciphertext with the secret key ("Dec")).
Drucker does not explicitly disclose being generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key.
However, Gentry discloses being generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key (Gentry: par. 0014 each ciphertext which is defined relative to one of the moduli q [] each row i of the matrix corresponding to an integer factor p, of the modulus q and each column j corresponding to a polynomial factor F1(X) of the m-th cyclotomic polynomial <I>m(X) modulo q; 0216 space and time by artificially "boosting" the modulus we use from q, up to P·q, for some "large" modulus P).
Therefore, it would have been obvious to a person of ordinary skill in the art, before the effective filing date of the claimed invention to combine the teachings of Gentry with the system/method of Drucker to include generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key. One would have been motivated to performing homomorphic evaluation of a function on input ciphertexts were encrypted using a public key of an encryption scheme (Gentry: par. 0006).
Regarding claim 2: Drucker in view of Gentry discloses the apparatus as claimed in claim 1.
Gentry further discloses wherein the modulus P is greater than the modulus Q of the second public key (Gentry: par. 0178 the plurality of moduli consist of products of smaller primes P1, where the t-th modulus qt, is the product of the first t smaller primes [] (where "smaller" in this context means smaller than q)).
The motivation is the same that of claim 1 above.
Regarding claim 3: Drucker in view of Gentry discloses the apparatus as claimed in claim 1.
Drucker further discloses wherein the processor is configured to receive the second public key from each of the plurality of terminal devices (Drucker: par. 0020 the client [] may use the Gen method to generate a pair of secret and public keys ("sk," "pk")), and generate the plurality of switching keys respectively corresponding to the received plurality of second public keys (Drucker: par. 0034 generates an ephemeral set of keys K (secret key "sk," public key "pk," evaluation key "evaluation1," skA=switchKey_{sk-sk1,}, skB=switchKey_ {sk1-sk})).
Regarding claim 4: Drucker in view of Gentry discloses the apparatus as claimed in claim 1.
Drucker further discloses wherein the processor is configured to generate the first public key based on the first secret key (Drucker: par. 0020 the client [] may use the Gen method to generate a pair of secret and public keys ("sk," "pk")), and
store the first secret key in a secure region of the memory to prevent the first secret key from being externally leaked from the electronic apparatus (Drucker: par. 0034 the keys may also be stored locally; par. 0020 the client may store the private key and may publish the public key).
Regarding claim 5: Drucker in view of Gentry discloses the apparatus as claimed in claim 1.
Drucker further discloses wherein the processor is configured to generate a first operation key based on the first secret key (Drucker: : par. 0036 generates the requested rotation key by rotating KSKa using the relevant key from the rotation1 key set), and
control the communication device to provide the first operation key to a first server device performing a homomorphic operation on a plurality of homomorphic ciphertexts (Drucker: par. 0058 the encrypted input data 224 using a homomorphic encryption evaluation key 226e and/or homomorphic encryption rotation keys 226r [] the homomorphic encryption key set 226 and encrypted input data 224 may be transmitted together from client DPS 214 to the Cloud 202).
Regarding claim 6: Drucker in view of Gentry discloses the apparatus as claimed in claim 5.
Drucker further discloses wherein the processor is configured to control the communication device to transmit the switching key to a second server device providing a homomorphic operation result of the first server device to each electronic apparatus (Drucker: par. 0036 generates the requested rotation key by rotating KSKa using the relevant key from the rotation1 key set and applying key-switching from secret key "sk1" to secret key "sk" by using key switching key sk-sk1).
Regarding claim 7: Drucker in view of Gentry discloses the apparatus as claimed in claim 1.
Gentry further discloses wherein the processor is configured to generate a first partial secret key and a second partial secret key that satisfy mutual linearity based on the first secret key (Gentry: par. 0033 generates a public key pk (and a plurality, N, of secret keys, sk for the homomorphic encryption scheme; par. 0143 four ciphertexts are combined via a linear operation (with coefficients 1,X, and (1+X)) to obtain the final result of this round function).
The motivation is the same that of claim 1 above.
Regarding claim 8: Drucker discloses a method for controlling an electronic apparatus, the method comprising:
storing a first secret key and a first public key corresponding to the first secret key (Drucker: fig. par. 0032 generates a principle set of keys (secret key "sk1," public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1"); par. 0034 the keys may also be stored locally);
receiving a second public key from a terminal device corresponding to a first user (Drucker: par. 0033 uploads (public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1"));
generating a switching key based on the second public key and the first secret key (Drucker: par. 0034 generates an ephemeral set of keys K (secret key "sk," public key "pk," evaluation key "evaluation1, "skA=switchKey_ { sk-sk1,}, skB=switchKey_ { sk1-sk} )); and
transmitting the first public key to the terminal device (Drucker: par. 0063 Org 320 may then transmit the HE public key 326pk, the HE evaluation key 326e, and the plurality of HE rotation keys 326r for the principal instance 350),
wherein the switching key is a key that enables a homomorphic ciphertext encrypted using the first public key to be decrypted using a second secret key corresponding to the second public key (Drucker: par. 0058 the HE processor 204 may then encrypt the prepared encrypted input data 224 using a homomorphic encryption public key 226pk to generate a set of encrypted input data 224; par. 0018 decrypt a ciphertext with the secret key ("Dec")).
Drucker does not explicitly disclose being generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key.
However, Gentry discloses being generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key (Gentry: par. 0014 each ciphertext which is defined relative to one of the moduli q [] each row i of the matrix corresponding to an integer factor p, of the modulus q and each column j corresponding to a polynomial factor F1(X) of the m-th cyclotomic polynomial <I>m(X) modulo q; 0216 space and time by artificially "boosting" the modulus we use from q, up to P·q, for some "large" modulus P).
Therefore, it would have been obvious to a person of ordinary skill in the art, before the effective filing date of the claimed invention to combine the teachings of Gentry with the system/method of Drucker to include generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key. One would have been motivated to performing homomorphic evaluation of a function on input ciphertexts were encrypted using a public key of an encryption scheme (Gentry: par. 0006).
Regarding claims 9-14: Claims 9-14 are similar in scope to claims 2-7, respectively, and are therefore rejected under similar rationale.
Regarding claim 15: Drucker discloses a non-transitory computer-readable recording medium storing a program for executing a method for controlling an electronic apparatus, wherein the method includes storing a first secret key and a first public key corresponding to the first secret key (Drucker: par. 0032 generates a principle set of keys (secret key "sk1," public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1"); par. 0034 the keys may also be stored locally),
receiving a second public key from a terminal device corresponding to a first user (Drucker: par. 0033 uploads (public key "pk1," evaluation key "evaluation1," and rotation keys "rotations1),
generating a switching key based on the second public key and the first secret key (Drucker: par. 0034 generates an ephemeral set of keys K (secret key "sk," public key "pk," evaluation key "evaluation1, "skA=switchKey_ { sk-sk1,}, skB=switchKey_ { sk1-sk} )), and
transmitting the first public key to the terminal device (Drucker: par. 0063 Org 320 may then transmit the HE public key 326pk, the HE evaluation key 326e, and the plurality of HE rotation keys 326r for the principal instance 350),
wherein the switching key is a key that enables a homomorphic ciphertext encrypted using the first public key to be decrypted using a second secret key corresponding to the second public key (Drucker: par. 0058 the HE processor 204 may then encrypt the prepared encrypted input data 224 using a homomorphic encryption public key 226pk to generate a set of encrypted input data 224; par. 0018 decrypt a ciphertext with the secret key ("Dec")).
Drucker does not explicitly disclose is generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key.
However, Gentry discloses is generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key (Gentry: par. 0014 each ciphertext which is defined relative to one of the moduli q [] each row i of the matrix corresponding to an integer factor p, of the modulus q and each column j corresponding to a polynomial factor F1(X) of the m-th cyclotomic polynomial <I>m(X) modulo q; 0216 space and time by artificially "boosting" the modulus we use from q, up to P·q, for some "large" modulus P).
Therefore, it would have been obvious to a person of ordinary skill in the art, before the effective filing date of the claimed invention to combine the teachings of Gentry with the system/method of Drucker to include generated using a modulus P that is coprime to a modulus Q of the second public key, the first secret key, and the second public key. One would have been motivated to performing homomorphic evaluation of a function on input ciphertexts were encrypted using a public key of an encryption scheme (Gentry: par. 0006).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Fahimeh Mohammadi whose telephone number is (571)270-7857. The examiner can normally be reached Monday - Friday 9:00 - 5:00.
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/FAHIMEH MOHAMMADI/ Examiner, Art Unit 2439
/LUU T PHAM/Supervisory Patent Examiner, Art Unit 2439
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