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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after allowance or after an Office action under Ex Parte Quayle, 25 USPQ 74, 453 O.G. 213 (Comm'r Pat. 1935). Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, prosecution in this application has been reopened pursuant to 37 CFR 1.114. Applicant's submission filed on 03/02/2026 has been entered.
DETAILED ACTION
Claims 1-20 are currently pending and have been considered below. Claims 1, 6 and 10 are independent claims.
Information Disclosure Statement
The information disclosure statements (IDS’s) submitted on 06/06/2025 is in compliance with provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Response to Arguments
Applicant’s arguments with respect to claims 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Rejections - 35 USC § 103
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 1-2, 6, 14 and 16-20 are rejected under 35 U.S.C. 103 as being Brown(US Patent No. 10116450 B1) in view of Weng (US Publication No. 20180041342 A1) in further view of Agrawal(US Publication No 20190164153 A1).
Regarding Claim 1:
Brown discloses: A computing device comprising: a communication interface(Brown, Col. 4-5, lines 66 and lines 1-3 the processor 114 coordinates or controls operation of other components of the device 102, such as, for example, user interfaces, communication interfaces, peripheral devices and possibly other components.);
and a processor to: determine that a received signature, produced and encrypted by a signer, is derived from a free state under a stateful signature scheme(Brown, Col. 16, lines 65-68 At 470, the verifying node 404 authenticates the verification key in the digital signature using the full authentication path and the public key obtained at 420…),
wherein the free state is a state that has not previously been used to derive a signing key or to generate a signature under the stateful signature scheme (Brown, Col. 17, lines 39-44, the signing entity in the MSS (e.g., signing device 402) may disregard the lost subtree data (and any unused signing/verification key pairs associated therewith) and subtree data associated with another subtree may be loaded from the non-volatile memory into the volatile memory);
Brown does not disclose:
in response to determining that the received signature is derived from the free state, decrypt the received signature and transmit the decrypted signature to a recipient via the communication interface
Weng discloses: in response to determining that the received signature is derived from the free state, decrypt the received signature(Weng, [0008], …decryption of the signature if the signature is encrypted, generates a comparison value using the received data and compares the comparison value and the received signature. When the comparison value and the signature are identical, the sender can be verified…);
and transmit the decrypted signature to a recipient via the communication interface(Weng, [0008], a sender generates a signature based on data and transmits the signature together with the data to a receiver. The receiver then extracts the signature from the data, eventually in combination with a decryption of the signature if the signature is encrypted, generates a comparison value using the received data and compares the comparison value and the received signature.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensures that the data has not been altered and that it originated from the expected sender, who used their corresponding private key to create the signature.
The motivation is to ensure the sender would have first created a hash of the original data and then encrypted that hash to form the signature. By decrypting the signature, the recipient can retrieve this original hash. They can then create their own hash of the received data and compare it to the decrypted hash.
and wherein the signer produces and encrypts the received signature without knowledge of whether the received signature is derived from the free state (Agrawal, [0030], A user operating a user device (e.g., one of validation nodes 106A-D, or a computing device in communication with a validation node) may initiate a transaction by generating a cryptographically signed message and sending the message to blockchain network 102… validation node that solves the block may provide the solution to the other validation nodes for verification, and ledger 104 maintained at each of validation nodes 106A-D can be updated to add the block to ledger 104 to effect the transaction. [0085], output transaction data to request their corresponding functions in platform smart contract 210. The transaction data may include a set of public keys of the accounts involved in the transaction, ciphertexts representing amounts if a transfer is involved, a signature generated by signing nonce 290 with private key 280, and a proof that is validated by validation node computing device 206 to effect the transaction. [0086], generate a fund transaction request to convert a cryptocurrency amount into tokens for platform smart contract 210. When platform smart contract 210 receives the fund transaction request, platform smart contract 210 may validate the cryptographic proof in the fund transaction request and invoke the Fund function).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensures that state usage is verified independently of the signer based on an accurate and current system state, thereby preventing inadvertent reuse of previously used states.
The motivation is to enhance consistency of state validation in systems where the signer may operate an outdated or unsynchronized view of state.
Regarding Claim 2:
The computing device of claim 1, Brown in view of Weng in further view of Agrawal teaches wherein the processor is to: determine that a second received signature, produced and encrypted by the signer (Brown, Col. 11, lines 13-16, the signing keys 202 a, and the verification keys 206 a) into its volatile memory from its non-volatile memory, and may use the signing keys 202 a and verification keys 206 a to generate digital signature),
is derived from a used state, wherein the used state is a state that has previously been used to derive a singing key or to generate a signature under the stateful signature scheme: in response to determining that the second received signature is derived from the used state(Brown, Col. 9, lines 15-27, the cryptographic hash tree 200 may have a large number of levels (e.g., with a height of approximately 20 levels), and may be too large to be entirely loaded into the volatile memory of a signing node. Thus, portions of the cryptographic hash tree 200 may need to be kept in non-volatile memory during digital signing operations. To keep track of which signing/verification pairs have been used already (since a signing key of an OTS scheme should not be used more than once), a state variable or index may be used. A main state variable may reside in the volatile memory with the portion of the cryptographic hash tree currently being used to sign messages (the one loaded into the volatile memory)),
delete the second received signature(Brown, Col. 14, lines 20-25, the signing keys 202 a, and the verification keys 206 a may be loaded into volatile memory from non-volatile memory. The data unit may be deleted from the non-volatile memory upon being loaded into the volatile memory, or may be deleted from the non-volatile memory upon loading another data unit into the volatile memory (e.g., upon exhaustion of the signing/verification key pairs in the initial data unit).).
Regarding Claim 6:
Brown discloses:
A non-transitory machine-readable medium storing instructions readable and executable by a processor of a computing device to: determine that the state is free to use as input derive to a signing key under the stateful signature scheme by determining that the state is indicated as being free state in a record, wherein the record is indicative of states that have not yet been used under the stateful signature scheme (Brown, Col. 17, lines 39-44, the signing entity in the MSS (e.g., signing device 402) may disregard the lost subtree data (and any unused signing/verification key pairs associated therewith) and subtree data associated with another subtree may be loaded from the non-volatile memory into the volatile memory)).
Brown does not disclose:
in response to determining that the state is free to use, decrypt the encrypted signature
Weng teaches:
in response to determining that the state is free to use, decrypt the encrypted signature (Weng, [0008], …decryption of the signature if the signature is encrypted, generates a comparison value using the received data and compares the comparison value and the received signature. When the comparison value and the signature are identical, the sender can be verified…);
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensures that the data has not been altered and that it originated from the expected sender, who used their corresponding private key to create the signature.
The motivation is to ensure the sender would have first created a hash of the original data and then encrypted that hash to form the signature. By decrypting the signature, the recipient can retrieve this original hash. They can then create their own hash of the received data and compare it to the decrypted hash.
Brown in view of Weng disclose:
receive, via an interface of the computing device, an encrypted signature and data that is indicative of a state used by a signer to generate the encrypted signature under a stateful signature scheme without knowledge of whether the state is free;
Agrawal discloses:
receive, via an interface of the computing device, an encrypted signature and data that is indicative of a state used by a signer to generate the encrypted signature under a stateful signature scheme without knowledge of whether the state is free; (Agrawal, [0085], transaction data may include a set of public keys of the accounts involved in the transaction, ciphertexts representing amounts if a transfer is involved, a signature generated by signing nonce 290 with private key 280, and a proof that is validated by validation node computing device 206 to effect the transaction [0126], using the state of the epoch that just concluded. Indeed, the user may not be in complete sync with the blockchain and a transaction could suffer some delay, but a good choice of epoch length would take care of these problems. Also, no more than one transfer or burn transaction (not one of each) should be generated per account in any epoch. (This restriction can be omitted if only confidentiality is desired.) For a transfer transaction);
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Agrawal in order to ensure that state dependent operations are validated against an accurate and current system state and to prevent improper reuse of previously used states.
The motivation is to enhance the integrity, consistency, and robustness of stateful signature generation in environments where state validity cannot be determined locally at the time generation.
Regarding Claim 14:
Brown discloses:
The computing device of claim 13, Brown in view of Weng in further view of Agrawal teach and transmit the second encrypted signature to a recipient via the communication interface in response to receiving the second indication(Brown, The example process 400 generates a digital signature for messages in a communication system using an MSS that utilizes an OTS scheme and subtree data for subtrees of a cryptographic hash tree (e.g., digitally signing messages sent between devices 102, 104 of FIG. 1 using the subtrees 214 of cryptographic hash tree 200 of FIGS. 2-3)) wherein the processor is to receive, from the entity, a second indication that the second encrypted signature has been decrypted by the entity (Weng, [0008], a sender generates a signature based on data and transmits the signature together with the data to a receiver. The receiver then extracts the signature from the data, eventually in combination with a decryption of the signature if the signature is encrypted):
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensures that the signature has been properly handled and is ready for its intended use.
The motivation is to ensure the confidentiality, integrity, and authenticity of sensitive information in a secure communication system by implementing an additional security verification step before the final transmission of a critical security element.
Regarding Claim 16:
The computing device of claim 1, Brown in view of Weng in further view of Agrawal teach wherein the processor is to verify the decrypted signature using a public key of the signer(Weng, [0032], According to a further embodiment, the computing entity is configured to decrypt the received signature using a public key of the sending device, before comparing the received signature with the comparison value.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensure the authenticity and integrity of the signed data, by establishing trust in the origin and contents of a message or file.
The motivation is to enhance a signature using the signer's public key provides essential security guarantees non-repudiation. This mechanism ensures that the message is genuine, has not been tampered with, and the sender cannot deny having sent it.
Regarding Claim 17:
The computing device of claim 16, Brown in view of Weng in further view of Agrawal teach wherein the processor is to transmit the decrypted signature to the recipient via the communication interface in response to verifying the decrypted signature using the public key of the signer(Weng, [0032], [0071], At the receiving device, the verification of signature takes the first operation 310 on received frames, excluding storing the hash values in the hash map 313 and then takes the second operation 320 with the public key of the sending device 10. The verification succeeds if the calculated hash value is the same as the value sent by the sending device 10.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensure unauthorized parties from intercepting and reading the decrypted data or the verification result during transmission.
The motivation is to enhance the transmission process is to ensure confidentiality and integrity of the communication, even after the digital signature has been verified. While the verification confirms the sender's identity and that the original data has not been tampered with.
Claims 3-5 and 7-9 are rejected under 35 U.S.C. 103 as being unpatentable over Brown (US Patent No. 10116450 B1) in view of Weng(US Publication No. 20180041342 A1) in further view of Agrawal(US Publication No. 20190164153 A1) and in further view of Misoczki (US Publication No. 20220078024 A1).
Regarding Claim 3:
Brown in view of Weng in view of Agrawal disclose:
The computing device of claim 1…
Brown in view of Weng in view of Agrawal do not disclose:
wherein the signature is to facilitate verification of a message signed with the signature by the signer
Misoczki discloses:
wherein the signature is to facilitate verification of a message signed with the signature by the signer(Misoczki, [0030], scheme of HBS is shown that uses Merkle trees along with a one-time signature (OTS) scheme 100, such as using a private key to sign a message and a corresponding public key to verify the OTS message).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to ensure authenticity, and integrity in electronic communications and transactions.
The motivation is to ensure that the verification process guarantees that the content of the message has not been altered or tampered with since it was signed
Regarding Claim 4:
The computing device of claim 3, Brown in view of Weng in further view of Agrawal and in further view of Misoczki teaches wherein the processor is to: receive the message via the communication interface along with the received signature, and, in response to determining that the received signature is derived from free state, instruct transmission of the message via the communication interface to the recipient(Misoczki, [0043], the message, M, and signature may then be sent by first device 310, e.g., via communication logic 342, to second device 350 via network communication link 390. In an embodiment, the message, M, may not be encrypted prior to transmission. In another embodiment, the message, M, may be encrypted prior to transmission. For example, the message, M, may be encrypted by cryptography logic 340 to produce an encrypted message. The message may be received by communication logic 382 and decrypted by cryptographic logic 380.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to ensure that a party cannot later deny they sent a message, received a message, or approved information..
The motivation is to ensure that the digital signature is created using the sender's private key and can be verified by anyone with the corresponding public key. This proves the message originated from the owner of that private key.
Regarding Claim 5:
The computing device of claim 3, Brown in view of Weng in further view Agrawal’s in further view of Misoczki teaches wherein the processor is to, in response to determining that the signature is derived from free state, instruct the signer to transmit the message to the recipient(Misoczki, [0046], Second device 350 further comprises a signing facility 370 comprising one or more hardware security module 371 which includes hash logic 372, signature logic, and verification logic 376. As described above, hash logic 372 is configured to hash (i.e., to apply a hash function to) a message (M) to generate a hash message (m′)).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to ensure that any subsequent alteration of the message would be detected because the signature would no longer be valid.
The motivation ensures that each signature is a unique event tied to a specific message and set of secure parameters. This strengthens the non-repudiation property, making it nearly impossible for the sender to later deny having sent the message, as the unique signature cannot be replicated without access to the secure "free state" generation process and the private key.
Regarding Claim 7:
Brown in view of Weng in further view of Agrawal disclose:
The non-transitory machine-readable medium of claim 6…
Brown in view of Weng in further view of Agrawal does not disclose:
wherein the instructions are readable and executable by the processor to: prior to determining that the state is free to use, verify that the data that it indicative of the state used by signer has not been modified in transit to the computing device
Misoczki discloses:
wherein the instructions are readable and executable by the processor to: prior to determining that the state is free to use, verify that the data that it indicative of the state used by signer has not been modified in transit to the computing device(Misoczki, [0047], In instances in which the second device is the verifying device, hardware security module 371 is configured to generate a verification signature based, at least in part, on the signature received from the first device and based, at least in part, on the received message representative (m′). For example, hardware security module 371 may configured to perform the same signature operations).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to ensure verifying the data has not been modified or altered by the device.
The motivation is to prevent an attacker from manipulating or replaying altered state-tracking data while the data is being transmitted from the singer to the computing device.
Regarding Claim 8:
Brown in view of Weng in further view of Agrawal disclose:
The non-transitory machine-readable medium of claim 6…
Brown in view of Weng in further view of Agrawal do not disclose:
wherein the instructions are readable and executable by the processor to: in response to determining that the state is not a free state, inform the signer that the state has been used previously
Misoczki discloses:
wherein the instructions are readable and executable by the processor to: in response to determining that the state is not a free state, inform the signer that the state has been used previously(Misoczki, [0056], Additionally, because HBS schemes in some renditions have a limited number of total signing operations based on the size of the tree, an attack on the signing system or an error in the signing system could cause a “wear-out” of the signing key where all possible counters are used up and the signing key cannot be used anymore).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki to improve the security of the system by preventing accidental state reuse.
The motivation is to ensure the that providing alerts to reduces the risk of producing invalid or insecure signatures and by enhancing the integrity of the signer’s key.
Regarding Claim 9:
Brown in view of Weng in further view of Agrawal disclose:
The non-transitory machine-readable medium of claim 6…
Brown in view of Weng in further view of Agrawal do not disclose:
wherein the instructions are readable and executable by the processor to verify the decrypted signature using a public key of the signer and the state used by the signer to generate the encrypted signature
Misoczki discloses:
wherein the instructions are readable and executable by the processor to verify the decrypted signature using a public key of the signer and the state used by the signer to generate the encrypted signature,(Misoczki, [0047], verification logic 376 may be configured to compare each verification message element to the corresponding public key element, pki. If each of the verification message element matches the corresponding public key element, pki, then the verification corresponds to success. In other words, if all of the verification message elements match the public key elements, pk1, pkL, then the verification corresponds to success).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng in further view of Agrawal Merkle signature scheme using subtrees by enhancing Brown in view of Weng in further view of Agrawal wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki to ensure the integrity of stateful signature operations.
The motivation is to enhance security by ensuring that only valid, correctly verified signatures are key, wherein any signature that fails verification is immediately deleted which protects the system from being tampered.
Regarding Claim 18: The non-transitory machine-readable medium of claim 9, Brown in view of Weng in further view of Agrawal and in further view of Misoczki teach wherein the instructions are readable and executable by the processor to instruct transmission of the decrypted signature to a recipient via the interface in response to successfully verifying the signature(Weng, [0032], [0071], At the receiving device, the verification of signature takes the first operation 310 on received frames, excluding storing the hash values in the hash map 313 and then takes the second operation 320 with the public key of the sending device 10. The verification succeeds if the calculated hash value is the same as the value sent by the sending device 10.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensure that only verified trustworthy signatures are transmitted.
The motivation is to maintain security and authenticity by transmitting decrypted signatures only after verification succeeds, thereby preventing the propagation of forged or tampered data and ensuring that the recipient receives only trusted signature information.
Regarding Claim 19:
The non-transitory machine-readable medium of claim 9, Brown in view of Weng in further view of Agrawal and in further view of Misoczki teach wherein the instructions are readable and executable by the processor to delete the decrypted signature in response to unsuccessfully verifying the signature(Weng, [0034], Based on the described sending device and receiving device, the verification of a signature generated as described may still be successful even if packet loss occurred during the data transmission, which may be a video transmission. As the signatures are generated dynamically and applied only to the data that has been received, it may be more difficult for an attacker to emulate a signature.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown’s Merkle signature scheme using subtrees by enhancing Brown’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Weng in order to ensure only authenticated signature remain in memory.
The motivation is to prevent retention of invalid or potentially malicious signature data, thereby protecting system integrity, reducing security exposure, and ensuring that only valid trusted signatures persist in the device.
Claims 10, 13 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over by Brown(US Patent No. 10116450 B1) in view of Agrawal(US Publication No. 20190164153 A1)
Regarding Claim 10:
Brown discloses: A computing device comprising: a communication interface(Brown, Col. 4-5, lines 66 and lines 1-3 the processor 114 coordinates or controls operation of other components of the device 102, such as, for example, user interfaces, communication interfaces, peripheral devices and possibly other components.);
and a processor to generate an encrypted signature, using a signing key that is derived from a candidate state of a stateful signature scheme (Brown, Col. 16, lines 65-68 At 470, the verifying node 404 authenticates the verification key in the digital signature using the full authentication path and the public key obtained at 420…);
instruct data comprising the encrypted signature to be sent via the communication interface to an entity that determines whether the candidate state is a free state that has not been used under the stateful signature scheme(Brown, (Brown, Col. 17, lines 39-44, the signing entity in the MSS (e.g., signing device 402) may disregard the lost subtree data (and any unused signing/verification key pairs associated therewith) and subtree data associated with another subtree may be loaded from the non-volatile memory into the volatile memory));
receive, from the entity via the communication interface, an indication that the encrypted signature has not been decrypted by the entity(Brown, Col. 1, lines 28-33, a Merkle signature scheme (MSS) utilizes a cryptographic hash tree and one-time signatures (OTS) to generate and verify digital signatures in a communication system. A cryptographic hash tree may be implemented by a binary tree whose nodes are based on outputs of hash functions);
determine, based on the indication, that the candidate state is not a free state(Brown, Col. 2, lines 64-67, subtree data may be loaded into volatile memory without the need to synchronize the state of which signing/verification key pairs associated with the subtree have been used);
and generate a second encrypted signature using a second signing key that is derived from a second candidate state of the stateful signature scheme responsive to making the determination (Brown, Col. 9, lines4 4-51, multiple computer systems may use a single cryptographic hash tree of an MSS to generate and verify digital signatures. In such implementations, the state variable may need to be shared among each of the computer systems in order to avoid using the same signing/verification keys twice. Real-time sharing and updating of the state variable among the various computer systems may be inefficient in some instances.)
Brown does not disclose:
generate an encrypted signature using a signing key that is derived from a candidate state of a stateful signature scheme without knowledge of whether the candidate state is a free state that has not yet been used under the stateful signature scheme
Agrawal discloses:
generate an encrypted signature using a signing key that is derived from a candidate state of a stateful signature scheme without knowledge of whether the candidate state is a free state that has not yet been used under the stateful signature scheme (Agrawal, [0085], These user algorithms may output transaction data to request their corresponding functions in platform smart contract 210. The transaction data may include a set of public keys of the accounts involved in the transaction, ciphertexts representing amounts if a transfer is involved, a signature generated by signing nonce 290, [0086], generate a fund transaction request to convert a cryptocurrency amount into tokens for platform smart contract 210. When platform smart contract 210 receives the fund transaction request, platform smart contract 210 may validate the cryptographic proof in the fund transaction [0126], using the state of the epoch that just concluded. Indeed, the user may not be in complete sync with the blockchain and a transaction could suffer some delay, but a good choice of epoch length would take care of these problems. Also, no more than one transfer or burn transaction (not one of each) should be generated per account in any epoch. (This restriction can be omitted if only confidentiality is desired.) For a transfer transaction);
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Weng’s Merkle signature scheme using subtrees by enhancing Brown in view of Weng’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure a sender generates a signature based on data and transmits the signature together with the data to a receiver as taught by Agrawal in order to ensure that state dependent operations are validated against an accurate and current system state and to prevent improper reuse of previously used states.
The motivation is to enhance the integrity, consistency, and robustness of stateful signature generation in environments where state validity cannot be determined locally at the time generation.
Regarding Claim 13:
The computing device of claim 10, Brown in view of Agrawal teach wherein the processor is to instruct data comprising the second encrypted signature to be sent via the communication interface to the entity (Brown, Col. 1, lines 28-33, a Merkle signature scheme (MSS) utilizes a cryptographic hash tree and one-time signatures (OTS) to generate and verify digital signatures in a communication system. A cryptographic hash tree may be implemented by a binary tree whose nodes are based on outputs of hash functions);
./,o
Regarding Claim 20:
The computing device of claim 10, Brown in view Agrawal teach wherein the entity comprises a second computing device(Brown, Col. 4, lines 56-61 the example processor 114 shown in FIG. 1 can include one or more chips or chipsets that include analog circuitry, digital circuitry or a combination thereof. In some cases, the processor 114 includes multiple processor devices such as, for example, one or more main processors and one or more co-processors.)
Claims 11-12 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Brown(US Patent No. 10116450 B1) in view of Agrawal(US Publication No. 20190164153 A1) in further view of Misoczki (US Publication No. 20220078024 A1).
Regarding Claim 11: Brown in view of Agrawal disclose:
The computing device of claim 10…
Brown in view of Agrawal does not disclose:
wherein the data is indicative of the candidate state used to derive the signing key
Misoczki discloses:
wherein the data is indicative of the candidate state used to derive the signing key(Misoczki, [0055], Hash-Based Signature (HBS) schemes such as the XMSS schemes described above are stateful, which means that some state (e.g., a counter) needs to be securely stored in between signature generations. If a signer reuses the same counter (which means reusing the same one-time signing key),).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to prevent the exposure of the private key from attacks.
The motivation is to ensure that a compromised private key allows a malicious actor to create signatures that appear legitimate. The recipient would verify this forged signature using the corresponding public key and be misled into believing the data is authentic and untampered.
Regarding Claim 12:
The computing device of claim 11, Brown in view of Agrawal in further view of Misoczki teach wherein the data is to protect an integrity of the candidate state(Misoczki, [0026], It is well-understood that cryptography allows for protection of data that is communicated online between individuals and entities and stored using various networks.).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to prevent the exposure of the private key from attacks.
The motivation is to ensure that a compromised private key allows a malicious actor to create signatures that appear legitimate. The recipient would verify this forged signature using the corresponding public key and be misled into believing the data is authentic and untampered.
Regarding Claim 15:
Brown in view of Agrawal disclose:
The computing device of claim 10…
Brown in view of Agrawal does not disclose:
wherein the processor is to update a database holding information on free states to use under the stateful signature scheme in response to making the determination
Misoczki discloses:
wherein the processor is to update a database holding information on free states to use under the stateful signature scheme in response to making the determination(Misoczki, [0043], After the signature is generated as described above, the message, M, and signature may then be sent by first device 310, e.g., via communication logic 342, to second device 350 via network communication link 390. In an embodiment, the message, M, may not be encrypted prior to transmission. In another embodiment, the message, M, may be encrypted prior to transmission. For example, the message, M, may be encrypted by cryptography logic 340 to produce an encrypted message. The message may be received by communication logic 382 and decrypted by cryptographic logic 380).
Before the effective filing date of the claimed invention, it would have been obvious to one with ordinary skill in the art to modify Brown in view of Agrawal’s Merkle signature scheme using subtrees by enhancing Brown in view of Agrawal’s wireless communication interface that provides wireless communication using various wireless protocols or standards to ensure that a signing facility which comprises one or more hardware security modules as taught by Misoczki in order to ensure security and prevent private key compromise.
The motivation is to update process that serves securely to track which one-time keys have been used and which are still available. This ensures that the system always uses a fresh, unused state for each new signature.
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Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAYASA SHAAWAT whose telephone number is (571)272-3939. The examiner can normally be reached on M-F, 8 AM TO 5 PM.
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/MAYASA SHAAWAT/
Examiner, Art Unit 2433
/JEFFREY C PWU/Supervisory Patent Examiner, Art Unit 2433
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