# US 2019/0378142 A1 · Biometric token for blockchain

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- Number: US 2019/0378142 A1
- Document ID: US20190378142A1
- Status: Published application
- Kind: A1
- Application number: 16/002,191
- Filed: 2018-06-07
- Published: 2019-12-12
- Earliest claimed: 2018-06-07
- Assignees: International Business Machines Corporation
- Applicants: International Business Machines Corporation
- Inventors: Shelby Solomon Darnell; Karthik Nandakumar; Sharathchandra Pankanti; Nalini K. Ratha
- Web page: https://patentgrep.com/patent/US20190378142A1

## CPC

- G06Q 20/40145: {Biometric identity checks}
- G06F 21/32: using biometric data, e.g. fingerprints, iris scans or voiceprints
- G06F 21/645: {using a third party}
- G06Q 20/102: {Bill distribution or payments}
- G06Q 20/38215: {Use of certificates or encrypted proofs of transaction rights}
- G06Q 20/407: {Cancellation of a transaction}
- H04L 9/0637: {Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]}
- H04L 9/085: {Secret sharing or secret splitting, e.g. threshold schemes}
- H04L 9/0891: {Revocation or update of secret information, e.g. encryption key update or rekeying}
- H04L 9/3231: {Biological data, e.g. fingerprint, voice or retina (network architectures or network communication protocols for supporting authentication of entities using biometrical features in a packet data network H04L63/0861)}
- H04L 9/3239: {involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD}
- H04L 9/3247: {involving digital signatures}
- H04L 9/3297: {involving time stamps, e.g. generation of time stamps}
- H04L 63/0807: {using tickets, e.g. Kerberos (cryptographic mechanisms or cryptographic arrangements for entity authentication using tickets or tokens H04L9/3213)}
- H04L 63/0861: {using biometrical features, e.g. fingerprint, retina-scan (cryptographic mechanisms or cryptographic arrangements for entity authentication using biological data H04L9/3231)}
- H04L 63/12: {Applying verification of the received information (cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32)}
- G06Q 2220/00: Business processing using cryptography
- H04L 9/50: {using hash chains, e.g. blockchains or hash trees}
- G06Q: INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

An example operation may include one or more of obtaining a first biometric sample of a user from a user device. extracting, by an issuing node of a permissioned blockchain network, a biometric template from the first biometric sample, encrypting the biometric template, distributing an issuetoken proposal comprising the encrypted biometric template to the blockchain network, and generating and distributing a biometric token to the user device. In response to the user indicating to the user device to redeem the biometric token, the method includes one or more of presenting, by the user device, the biometric token to a verifying node of the blockchain network, validating, by the verifying node, the biometric token, receiving, by the verifying node, a second biometric sample from the user device, distributing a redeemtoken proposal to the blockchain network, committing a transaction corresponding to the biometric token, to the blockchain network, and invalidating the biometric token.

## Claims

### Claim 1

A system, comprising:
a user device, comprising one or more biometric sensors; and
a permissioned blockchain network, comprising:
an issuing node, configured to:
receive a first biometric sample from the user device;
extract a biometric template from the first biometric sample;
encrypt the biometric template;
distribute an issuetoken proposal to the blockchain network based on the encrypted biometric template;
generate and distribute a biometric token to the user device; and
a verifying node, in response to the user indicates to the user device to redeem the biometric token, configured to:
receive the biometric token from the user device;
validate the biometric token;
receive a second biometric sample from the user device;
distribute a redeemtoken proposal to the blockchain network, the blockchain network configured to commit a transaction corresponding to the biometric token and invalidate the biometric token.

### Claim 2 (depends on 1)

The system of claim 1, wherein prior to the issuing node receives the first biometric sample, the user device initiates the transaction, the blockchain network verifies an identity for the user, and the blockchain network determines the transaction can be performed by the blockchain network.

### Claim 3 (depends on 1)

The system of claim 1, wherein the issuetoken proposal comprises:
an enrollment time corresponding to the first biometric sample; and
an expiry time for the biometric token,
wherein the blockchain network invalidates the biometric token and cancels the transaction in response to the expiry time is prior to a current time, wherein blockchain nodes verify validity of the issuetoken proposal comprises:
a blockchain node has signed the issuetoken proposal; and
the expiry time is later than the enrollment time but less than the current time.

### Claim 4 (depends on 3)

The system of claim 3, wherein in response to the issuing node distributes the issuetoken proposal, the blockchain network records the issuetoken proposal in a shared ledger, constructs, encrypts and signs the transaction metadata, the transaction metadata comprising an issuing node identifier, a token identifier, a transaction identifier, the enrollment time, the expiry time, and the encrypted biometric template, the transaction metadata signed using a private key of the issuing node in order to generate the biometric token.

### Claim 5 (depends on 4)

The system of claim 4, wherein the verifying node validates the biometric token comprises the verifying node:
decrypts the transaction metadata;
verifies the biometric token has not expired based on the expiry time and the current time;
verifies, through the shared ledger, the biometric token has not been redeemed or revoked; and
verifies a hash of the encrypted biometric template is the same as a hash stored in the blockchain network.

### Claim 6 (depends on 4)

The system of claim 4, wherein in response to receipt of the second biometric sample from the user device, the verifying node:
extracts a biometric query from the second biometric sample; and
constructs the redeemtoken proposal, the redeemtoken proposal comprising the token identifier, the transaction identifier, a request type, the enrollment time, the expiry time, and a cryptographic hash of the biometric query.

### Claim 7 (depends on 1)

The system of claim 1, wherein in response to one of a desire or need to cancel the transaction, the verifying node configured to:
distribute a revoketoken proposal to the blockchain network; and
cancel the transaction, by the blockchain network.

### Claim 8

A method, comprising:
obtaining a first biometric sample of a user from a user device;
extracting, by an issuing node of a permissioned blockchain network, a biometric template from the first biometric sample;
encrypting the biometric template;
distributing an issuetoken proposal comprising the encrypted biometric template to the blockchain network;
generating and distributing a biometric token to the user device;
in response to the user indicating to the user device to redeem the biometric token:
presenting, by the user device, the biometric token to a verifying node of the blockchain network;
validating, by the verifying node, the biometric token;
receiving, by the verifying node, a second biometric sample from the user device;
distributing a redeemtoken proposal to the blockchain network;
committing a transaction corresponding to the biometric token, to the blockchain network, and
invalidating the biometric token.

### Claim 9 (depends on 8)

The method of claim 8, wherein prior to obtaining the first biometric sample, the method further comprising:
initiating the transaction, by the user device;
verifying an identity for the user, by the blockchain network; and
determining the transaction can be performed by the blockchain network.

### Claim 10 (depends on 8)

The method of claim 8, wherein the issuetoken proposal comprises:
an enrollment time corresponding to the first biometric sample; and
an expiry time for the biometric token,
wherein the blockchain network invalidates the biometric token and cancels the transaction in response to the expiry time is prior to a current time, wherein blockchain nodes verify validity of the issuetoken proposal comprises:
a blockchain node has signed the issuetoken proposal; and
the expiry time is later than the enrollment time but less than the current time.

### Claim 11 (depends on 10)

The method of claim 10, wherein in response to distributing the issuetoken proposal, the method further comprising:
recording the issuetoken proposal in a shared ledger;
constructing transaction metadata, the transaction metadata comprising an issuing node identifier, a token identifier, a transaction identifier, the enrollment time, the expiry time, and the encrypted biometric template;
encrypting the transaction metadata; and
signing the transaction metadata using a private key of the issuing node in order to generate the biometric token.

### Claim 12 (depends on 11)

The method of claim 11, wherein validating the biometric token comprising:
decrypting the transaction metadata;
verifying the biometric token has not expired based on the expiry time and the current time;
verifying, through the shared ledger, the biometric token has not been redeemed or revoked; and
verifying a hash of the encrypted biometric template is the same as a hash stored in the blockchain network.

### Claim 13 (depends on 11)

The method of claim 11, wherein in response to receiving a second biometric sample from the user device, the method further comprising:
extracting, by the verifying node, a biometric query from the second biometric sample; and
constructing the redeemtoken proposal, the redeemtoken proposal comprising the token identifier, the transaction identifier, a request type, the enrollment time, the expiry time, and a cryptographic hash of the biometric query.

### Claim 14 (depends on 8)

The method of claim 8, wherein in response to one of a desire or need to cancel the transaction, the method further comprising:
distributing a revoketoken proposal to the blockchain network; and
cancelling the transaction, by the blockchain network.

### Claim 15

A non-transitory computer readable medium comprising instructions, that when read by a processor, cause the processor to perform:
obtaining a first biometric sample of a user from a user device;
extracting, by an issuing node of a permissioned blockchain network, a biometric template from the first biometric sample;
encrypting the biometric template;
distributing an issuetoken proposal comprising the encrypted biometric template to the blockchain network;
generating and distributing a biometric token to the user device;
in response to the user indicating to the user device to redeem the biometric token:
presenting, by the user device, the biometric token to a verifying node of the blockchain network;
validating, by the verifying node, the biometric token;
receiving, by the verifying node, a second biometric sample from the user device;
distributing a redeemtoken proposal to the blockchain network;
committing a transaction corresponding to the biometric token, to the blockchain network, and
invalidating the biometric token.

### Claim 16 (depends on 15)

The non-transitory computer readable medium of claim 15, wherein prior to obtaining the first biometric sample, the processor performs:
receiving the transaction, from the user device;
verifying an identity for the user, by the blockchain network; and
determining the transaction can be performed by the blockchain network.

### Claim 17 (depends on 15)

The non-transitory computer readable medium of claim 15, wherein the issuetoken proposal comprises:
an enrollment time corresponding to the first biometric sample; and
an expiry time for the biometric token,
wherein the blockchain network invalidates the biometric token and cancels the transaction in response to the expiry time is prior to a current time, wherein blockchain nodes verify validity of the issuetoken proposal comprises:
a blockchain node has signed the issuetoken proposal; and
the expiry time is later than the enrollment time but less than the current time.

### Claim 18 (depends on 17)

The non-transitory computer readable medium of claim 17, wherein in response to distributing the issuetoken proposal, the processor performs:
recording the issuetoken proposal in a shared ledger;
constructing transaction metadata, the transaction metadata comprising an issuing node identifier, a token identifier, a transaction identifier, the enrollment time, the expiry time, and the encrypted biometric template;
encrypting the transaction metadata; and
signing the transaction metadata using a private key of the issuing node in order to create the biometric token.

### Claim 19 (depends on 18)

The non-transitory computer readable medium of claim 18, wherein validating the biometric token comprising the processor performs:
decrypting the transaction metadata;
verifying the biometric token has not expired based on the expiry time and the current time;
verifying, through the shared ledger, the biometric token has not been redeemed or revoked; and
verifying a hash of the encrypted biometric template is the same as a hash stored in the blockchain network.

### Claim 20 (depends on 18)

The non-transitory computer readable medium of claim 18, wherein in response to receiving a second biometric sample from the user device, the processor performs:
extracting, by the verifying node, a biometric query from the second biometric sample; and
constructing the redeemtoken proposal, the redeemtoken proposal comprising the token identifier, the transaction identifier, a request type, the enrollment time, the expiry time, and a cryptographic hash of the biometric query.