DETAILED ACTION
This Office Action is in response to the Arguments filed on 02/17/2026.
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 .
Claim Objections
Claims 55 and 57 are objected to because of the following informalities: .
Claim 55 recites “..the KD5 hash…” in lines 3 and 5. It is believed that this limitation should be changed to “..the MD5 hash..”
Claim 57 is also objected for the same rationale as claim 55 above. Appropriate correction is required.
Response to Amendment
Regarding claims 28, 36-37, 41, 44, and 46-47, the 35 USC 112 2nd and 101 rejections made in the Non-Final Rejection dated 11/17/2026 are hereby withdrawn due to the Amendments filed on 02/17/2026.
Response to Arguments
Applicant’s arguments with respect to claims 28, 44 and all their dependent claims have been considered but are moot in view of the new ground(s) of rejection as detailed below.
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, 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.
Claims 28-35, 44-45 and 48-57 are rejected under 35 U.S.C. 103 as being unpatentable over Campagna et al. (US Patent 12,095,909 B1-hereinafter Campagna) and further in view of Teppler (US 2009/0083372 A1-hereinafter Teppler).
Regarding claim 28, Kim discloses a method performed by a device, the method comprising:
obtaining an original key (at least column 1, lines 52-59, column 3, lines 19-34, master key is obtained);
obtaining a local encryption key for encrypting the original key (at least column 1, lines 62-65, domain key is obtained);
encrypting the original key using the obtained local encryption key (at least column 1, lines 62-65, the master key is encrypted with the domain key to generate encrypted key token (EKT) ); and
saving the encrypted original key (at least column 1, lines 62-67, the the EKT is stored).
Kim does not disclose the method is performed by a device using network time protocol (NTP) and that the original key is an NTP key.
However, Teppler discloses a method is performed by a device using network time protocol (NTP) and a key used to certify time and date (NTP key) of a digital data file (at least [0224][0239]-[0241], NTP and key).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Teppler into the method of Campagna to enhance security to the distribution of trusted time among devices.
Regarding claim 29, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler also disclose encrypting the original NTP key further comprises encrypting the original NTP key using a hardware module (Campagna-at least column 4, lines 37-47, the master key is encrypted with a domain key of a hardware security module (HSM); Teppler-at least [0224][0347], HSM is used to sign/encrypt the data file).
Regarding claim 30, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler also disclose the obtained local encryption key comprises a private key of a hardware module (Campagna-at least column 4, lines 40-43, domain key is a secret/secret key; Teppler-at least [0374], private key of HSM is used to signing the data file).
Regarding claim 31, Campagna and Teppler disclose the method according to claim 29. Campagna and Teppler also disclose the hardware module comprises a Hardware Security Module (HSM) or a Trusted Platform Module (TPM) (Campagna- at least column 4 lines 37-47, HSM; Teppler-at least [0374], HSM).
Regarding claim 32, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler also disclose encrypting the original NTP key further comprises encrypting the original NTP key using a software (Campagna- least column 4, lines 37-47, the master key is encrypted with a domain key; Teppler at least [0079], the signing of the data file is done using the signer software).
Regarding claim 33, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler also disclose saving the encrypted NTP key further comprises adding an indication indicating that the NTP key is an encrypted NTP key (Campagna-at least column 5, lines 42-46, i.e.: mapping indicates information such as association and storage location of EKT and encrypted value; Teppler-[0224][0239]-[0241], NTP and key).
Regarding claim 34, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler also disclose saving the encrypted NTP key further comprises indicating an encryption algorithm used for encrypting the original NTP key (Campagna-at least column 5, lines 48-51, mapping also indicates algorithm; Teppler-[0224][0239]-[0241], NTP and key).
Regarding claim 35, Campagna and Teppler disclose the method according to claim 28. Campagna and Teppler disclose also disclose saving the encrypted NTP key further comprises saving the encrypted NTP key to a file system of the device (Campagna-at least figures 6 &11A [0007]-[0009] [0145] [0224], data file is saved to a file system; Teppler-[0224][0239]-[0241], NTP and key).
Claim 44 is rejected for the same rationale as claim 28 above.
Claim 45 is rejected for the same rationale as claim 29 above.
Claim 48 is rejected for the same rationale as claim 29 above.
Claim 49 is rejected for the same rationale as claim 31 above.
Claim 50 is rejected for the same rationale as claim 32 above.
Claim 51 is rejected for the same rationale as claim 33 above.
Claim 52 is rejected for the same rationale as claim 34 above.
Claim 53 is rejected for the same rationale as claim 35 above.
Regarding claim 54, Campagna and Teppler disclose the device according to claim 53. Campagna and Teppler also disclose the memory contains instructions executable by the processing circuitry whereby the device is further configured to:
receive an NTP packet comprising a cryptographic signature (Campagna-at least column 6, lines 17-32, i.e.: encrypted value is received/obtained; Teppler- [0224][0239]-[0241], NTP and key);
retrieve the encrypted NTP key from the file system (Campagna-at least column 6, lines 17-32, EKT is retrieved; Teppler- [0224][0239]-[0241], NTP and key);
use the local encryption key to decrypt the encrypted NTP key retrieved from the file system (Campagna-at least column 4, lines 44-17, domain key is used to decrypt EKT; Tepper-at least [0224][0239]-[0241], NTP and key);
attempt to authenticate the NTP packet by checking the cryptographic signature comprised in the NTP packet using the decrypted NTP key (Campagna-column 6, lines 42-48, decrypting the EKT to obtain a master key, then the master key is used to verify if it can decrypt the encrypted value; Teppler-at least [0224][0239]-[0241], NTP and key).
Regarding claim 55, Campagna and Teppler disclose the device according to claim 54. Campagna and Teppler also obviously disclose the original NTP key is an Message-Digest Algorithm 5 (MD5) key, wherein the NTP packet includes an MD5 hash computed over the MD5 key, wherein the KD5 hash is the cryptographic signature, and the wherein the memory contains instructions executable by the processing circuitry whereby the device is configured to check the cryptographic signature by checking the KD5 hash using the decrypted NTP key (Campagna-column 6, lines 42-48, decrypting the EKT to obtain a master key, then the master key is used to verify if it can decrypt the encrypted value; Teppler-at least [0224][0239]-[0241][0246], MD5 algorithm, Message Digest 5).
Claim 56 is rejected for the same rationale as claim 54 above.
Claim 57 is rejected for the same rationale as claim 55 above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PHY ANH TRAN VU whose telephone number is (571)270-7317. The examiner can normally be reached Monday-Friday 7 am-1 pm.
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/PHY ANH T VU/ Primary Examiner, Art Unit 2438 ,
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