KR102197218B1 - System and method for providing distributed id and fido based block chain identification - Google Patents

Abstract

Disclosed are a system and a method for providing a distributed ID and FIDO-based block chain identification card. According to one embodiment, the method for providing an identification card performed in an authentication server comprises the steps of: configuring a distributed identification environment to manage authentication devices based on distributed IDs; registering a user using an authentication device associated with the electronic device of the user whose identity is confirmed in the configured distributed identity verification environment; receiving a document signing request from the registered user; and approving the document through an electronic signature using an authentication device associated with the electronic device of the counterpart user as the document is read from the counterpart user.

Description

System and method to provide distributed ID and FIDO-based blockchain ID {SYSTEM AND METHOD FOR PROVIDING DISTRIBUTED ID AND FIDO BASED BLOCK CHAIN IDENTIFICATION}

The description below is about a distributed ID and FIDO-based blockchain identification system.

When explaining the contract, the individual's identity is verified with an offline ID and then signed by the individual. These signatures are verified in a visual way with expert help. In the case of a handwritten signature, it must be requested to a handwriting appraiser to discriminate between the original and forged, and it takes about 2 to 7 days as well as the request fee. In order to solve this problem, an electronic signature method was introduced. In the case of electronic signatures, it is possible to immediately verify the original and counterfeit signatures programmatically.

Meanwhile, DID is a cutting-edge identification technology that is currently undergoing international standardization. The web standards organization W3C has established standard data formats for DID identifiers and certificates. The Decentralized Identity Foundation (DIF) consortium, including Microsoft and IBM, is standardizing the method of finding and storing DID identifiers and certificates on the network. In this way, if the cryptographic certificate of DID is used, only necessary parts of personal information can be presented and a credible cryptographic certificate can be attached, thereby protecting privacy.

By combining FIDO authentication with the distributed ID system, a practical and safe identification card system and method can be provided.

It is possible to provide a document approval method and system that verifies the integrity of documents and provides non-repudiation functions for approval by using secure and highly compatible technologies and cryptographically leaving evidence of document approval.

The method of providing an identification card performed in an authentication server includes: configuring a distributed identification environment for managing an authentication device based on a distributed ID; Registering a user using an authentication device associated with an electronic device of a user whose identity has been verified in the configured distributed identification environment; Receiving a request for payment of a document from the registered user; And approving the document through an electronic signature using an authentication device associated with the electronic device of the counterpart user as the document is read by the counterpart user.

The configuring of the distributed identification environment may include issuing an identification card based on a distributed ID to the user; And verifying the issued distributed ID-based identification card, wherein the issuing of the distributed ID-based identification card to the user comprises: FIDO using a FIDO authenticator as the identity of the user is confirmed face-to-face or non-face-to-face by the issuer. Using the user's public key obtained through the registration process, a DID document is created and stored in the blockchain, the user's DID identifier is determined, the user's DID identifier is issued to the user, and the user's It may include the step of generating a DID certificate (Verifiable claim) using the identity information checked through identity verification and the user's DID identifier and storing it in the blockchain.

In verifying the issued distributed ID-based identification card, as the DID identifier of the user is presented from the user to the verifier, the FIDO authentication process is performed using a FIDO authenticator, and the verifier is the DID ID presented by the user. Using the DID document and DID certificate in the blockchain, check whether the public key used in the FIDO authentication process matches the public key existing in the DID document, and check the digital signature of the issuer present in the DID certificate. It may include the step of verifying the identification card based on the distributed ID of the user by checking.

The step of registering the user may include issuing a DID value for the user through the user's FIDO registration process as the user's identity is confirmed, and using the user's public key confirmed through the FIDO registration process. Generating a document and storing it in the blockchain, and storing the DID certificate generated using the user's DID value and the identity information obtained through the user's identity verification in the blockchain.

In the step of approving the document, the document is approved or rejected as the document requested for payment from the counterpart user is read, and a DID certificate is generated based on the electronic signature verified through the FIDO authentication process with the counterpart user. And storing it in the blockchain.

In the step of approving the document, when the document requested for approval is to be approved by a plurality of counterpart users, the document is hashed as the document is confirmed by the first counterpart user, and the approval request from the first counterpart user Metadata is generated using the approval of the documented document, the approval time of the approved document and the identification information of the first counterpart user, and the hash value generated using the hashed document and the metadata In response to a request for FIDO authentication to the first counterpart user, the digital signature for the generated first hash value is received from the first counterpart user using the FIDO authenticator, and the document is confirmed from the second counterpart user. Accordingly, metadata is generated using whether or not the second counterpart user approves the document requested for payment, the approval time at which the document requested for payment is approved, and the identification information of the second counterpart user, and from the first counterpart user The second hash value is generated by using the generated hash value and the metadata generated from the second counterpart user, and the second counterpart user requests FIDO authentication for the generated second hash value. It may include receiving from the counterpart user that the digital signature for the generated second hash value is transmitted using the FIDO authenticator.

The authentication system according to an embodiment provides integrity verification and non-repudiation functions in a standard manner based on an asymmetric password, so that when forgery or alteration occurs in a document, the approval can be invalidated and the fact of the payment can be prevented from being denied. have.

The authentication system according to an embodiment may apply a FIDO authentication protocol to an electronic signature for a document.

The authentication system can use the service in any environment such as PC, authentication token, mobile, etc., and can be provided to use a convenient authentication method such as biometric authentication.

The authentication system can minimize the installation of additional programs or hardware introduction to the user.

The authentication system can improve compatibility and safety by managing the FIDO authenticator based on distributed ID.

1 is an example for explaining a distributed identification environment according to an embodiment.
2 is a block diagram illustrating the configuration of an authentication system according to an embodiment.
3 to 6 are diagrams for explaining a DID data structure according to an embodiment.
7 is a diagram illustrating an operation of issuing a distributed ID identification card in an authentication system according to an embodiment.
8 is a diagram for describing an operation of verifying a distributed ID identification card in an authentication system according to an embodiment.
9 is a diagram illustrating an operation of registering a user in an authentication system according to an exemplary embodiment.
10 is a diagram for describing an operation of paying a document in an authentication system according to an embodiment.
11 is a diagram for describing a sequential approval operation according to an approval line in an authentication system according to an embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

1 is an example for explaining a distributed identification environment according to an embodiment.

The concept called Decentralized ID, or Self-sovereign ID, receives an ID or certificate digitally, stores it by the user himself, and It means a proof system that can be presented as much as possible. In distributed ID, a digital certificate is issued through a predetermined authentication procedure like a public certificate and stored in the user's own electronic device. And when presenting a certificate, it shows that you are the owner of the certificate by signing with a private key corresponding to the public key in the certificate. Therefore, the core function in the use of distributed ID is the part handling the private key, and the easiest and safest way for an individual to handle the private key is to use an authentication device (for example, FIDO). In the embodiment, a practical and safe identification card system will be described by combining FIDO authentication with a distributed ID system.

After confirming the identity of the user 120, the issuer 110 may associate the obtained identity information with the authentication device by confirming the identity of the user 120. For example, the issuer 110 may associate the FIDO authenticator with the identity information of the user 120. In the embodiment, the issuer 110 may be anyone, as well as an accredited certification authority (CA) recognized by the state. However, the person who receives the ID must authenticate the issuer.

User 120 may have a FIDO authenticator. In other words, it holds the private key. For example, authentication may be performed using a private key stored in the FIDO authenticator, and authentication may be performed using a password or biometric information stored in the FIDO authenticator.

The verifier 130 may verify the identification card presented by the user. The verifier 130 may verify the signed data.

The storage 140 may store user identification information and a public key of the FIDO authenticator. At this time, the storage 140 may store data based on a block chain. The storage 140 may store the DID certificate in the user's electronic device (eg, PC, smart phone).

In addition, you can check whether the DID certificate has been revoked in the blockchain. According to the embodiment, since the servers are distributed, data tampering is impossible and it is difficult to perform a DoS attack.

2 is a block diagram illustrating the configuration of an authentication system according to an embodiment.

The processor of the authentication system 100 may include a distributed identity environment configuration unit 210, a user registration unit 220, a payment request unit 230, and a document approval unit 240. These may be expressions of different functions performed by the processor according to a control command provided by the program code stored in the authentication system of the processor.

The distributed identity environment configuration unit 210 may configure a distributed identity verification environment that manages authentication devices based on distributed ID. The distributed identity environment configuration unit 210 may issue a distributed ID-based identification card to a user and verify the issued distributed ID-based identification card. As the identity of the user is verified face-to-face or non-face-to-face from the issuer, the distributed identity environment configuration unit 210 generates a DID document using the user's public key obtained through the FIDO registration process using the FIDO authenticator and blocks it. Store in the chain and determine the user's DID identifier, issue the determined user's DID identifier to the user, and create a DID certificate (Verifiable claim) using the user's identity information and the user's DID identifier confirmed through the user's identity verification. Can be stored in the blockchain. As the DID identifier of the user is presented from the user to the verifier, the distributed identity environment configuration unit 210 performs the FIDO authentication process using the FIDO authenticator, and the verifier uses the DID identifier presented from the user to access the DID document and You can check the DID certificate to see if the public key used in the FIDO authentication process matches the public key existing in the DID document, and verify the user's distributed ID-based identification card by checking the issuer's digital signature in the DID certificate. have.

As the user's identity is verified, the user registration unit 220 issues a DID value for the user through the user's FIDO registration process, and generates a DID document using the user's public key verified through the FIDO registration process. And the DID certificate generated using the user's DID value and the identity information obtained through the user's identity verification can be stored in the blockchain.

The payment request unit 230 may receive a request for payment of a document from a registered user.

As the document is viewed by the counterpart user, the document approval unit 240 may approve the document through an electronic signature using an authentication device associated with the counterpart user's electronic device. The document approval unit 240 generates a DID certificate based on the electronic signature verified through the FIDO authentication process with the counterpart user as the document is approved or rejected as the document requested for payment from the counterpart user is read. Can be saved. When a document requesting approval is to be approved by a plurality of counterpart users, the document approval unit 240 hashes the document according to the confirmation of the document from the first counterparty user, and whether or not to approve the document requested for approval from the first counterparty user. , FIDO authentication to the first counterparty user for the hash value generated using the hashed document and the generated hash value using the first counterparty user's identification information and the approval time when the document requested for payment is approved In response to requesting, the digital signature for the first hash value generated using the FIDO authenticator is received from the first counterpart user, and the document is confirmed by the second counterpart user. Metadata is created using the approval status, the approval time of the document requested for approval, and the identification information of the second counterpart user, and the hash value generated from the first counterpart user and the metadata generated from the second counterpart user As a result of generating a second hash value and requesting FIDO authentication for the generated second hash value to the second counterpart user, the digital signature for the second hash value generated using the FIDO authenticator is transmitted from the second counterpart user. Can be received.

3 to 6 are diagrams for explaining a DID data structure according to an embodiment.

Referring to Figure 3, a digital identity document (DID document) refers to a data structure that declares an identifier to indicate a subject such as a person or an institution in the DID system, and is composed in a format including an identifier and a public key. Can be. DIDs can be stored on the blockchain in a secure and verifiable manner in a distributed environment. For example, DIDs can be stored in the blockchain along with attributes, public keys, and expiration dates.

Referring to FIG. 4, in general, a value derivable from a public key may be used as the DID identifier value. For example, in the case of an Ethereum account address, it can be defined as Address = Last160bits (Hash(PublicKey)). The owner of the identifier can prove that it is the owner of the identifier by signing the data with the private key corresponding to the identifier. In this way, when linking the identifier and the public key, a specific encryption algorithm must be used. For example, if you want to store the DID on the Ethereum blockchain, all users must have a private key of the secp256k1 algorithm. In the embodiment, it will be described to present an identification card system based on a distributed ID and FIDO authentication process. In the FIDO standard, FIDO certified devices are not limited to any one of asymmetric algorithms including RSA, secp25641, and secp256k1.

Thus, the identifier and the public key are not directly related. More specifically, the public key is stored in a smart contract on the blockchain, and the identifier is set to indicate where the public key is located on the blockchain.

The following is an example of a DID identifier (Decentralized Identifier).

For example,'teeware' in number 1 represents the name representing the DID implementation method, and '0x22B84d5FFeA8b801C0422AFe752377A64Aa738c2' in number 2 means the Ethereum address of the smart contract where the public key is stored, and '1234' in number 3 is public on the smart contract. It means the position of the key.

Referring to FIG. 5, a diagram for explaining a DID document and a DID certificate (verifiable claim). The DID document is a document that links an identifier and a public key. The DID certificate is a certificate that connects an identifier and a claim, and it includes the issuing authority's digital signature, so that the validity of the certificate can be verified (verifiable). Referring to FIG. 6, an example of a DID certificate is shown. 610 is the identifier of the subject subject to the certificate, 620 is the fact to be proved, and 630 is the issuer's electronic signature.

7 is a diagram for describing an operation of issuing a distributed ID identification card in an authentication system according to an embodiment.

Identification may be requested from the user. For example, user's personal information (eg, name, email, phone number, etc.) may be input. The issuer can verify the user's identity face-to-face or non-face-to-face (1). A FIDO-based registration process can be performed between the server (authentication system) and the user. The user can register the FIDO certified device connected to the electronic device to the server. The user's public key generated in the FIDO-based registration process between the server and the user can be delivered to the issuer (3). The issuer can create a DID document using the user's public key and store it in the blockchain, and by storing it in the blockchain, the user's DID identifier can be determined (4). The issuer can issue the determined user's DID identifier to the user (5). The issuer can generate a DID certificate using the user's identity information and DID identifier obtained through identity verification and store it in the blockchain (6).

8 is a diagram for describing an operation of verifying a distributed ID identification card in an authentication system according to an embodiment.

The verifier can check the DID identifier presented by the user (1). FIDO authentication may be performed between a user and a server (2). In this case, as the server performs FIDO authentication between the user and the server, it may be determined whether authentication is successful. The server can transmit the FIDO public key verified through FIDO authentication between the user and the server and whether the authentication was successful (3). The validator can search DID documents and DID certificates using the DID identifier on the blockchain (4). The verifier can check whether the public key key used for FIDO authentication matches the public key key of the DID document. The verifier can check whether the digital signature of the issuer in the DID certificate is correct. At this time, if any one of the intermediate processes including (1) to (4) fails, it is determined that the identification verification has failed.

9 is a diagram illustrating an operation of registering a user in an authentication system according to an exemplary embodiment.

In the embodiment, a document approval process of a company will be described through a blockchain/asymmetric encryption and trusted execution environment based on FIDO authentication technology. Referring to FIG. 9, a process of registering a user will be described.

The HR team can verify an employee's identity through face-to-face or non-face-to-face (1). For example, an employee's account may be collectively created through a personnel team, or a user's account may be newly created through membership registration from an employee. As the employee's account is created, the FIDO registration process between the server and the employee can be performed. For example, employees can easily log in to the server without a password by registering a FIDO authenticator. The server (authentication system) may be an application server implementing FIDO and document approval functions. The FIDO authenticator can be registered on the server by the employee. In this case, user authentication may be performed through the FIDO authenticator. As the FIDO authenticator is registered by the employee, the DID value for the employee can be issued from the server (3). The server may generate a DID document using the employee's public key obtained as the FIDO authenticator is registered by the employee, and store the generated DID document in the storage (4). In this case, the storage may be a database or a blockchain in which documents and electronic signatures are stored. For example, the DID document can be stored in the following format.

The server can input the employee's DID value and the identity information obtained through the employee's identity verification to a CA (5). Here, the accredited certification authority (CA) is the root of the authentication chain that guarantees the employee's identity information. The accredited certification authority (CA) can generate a DID certificate using the employee's DID value and the employee's identity information and store it in the storage (6). For example, the DID certificate can be stored in the storage in the following format.

10 is a diagram for describing an operation of paying a document in an authentication system according to an embodiment.

After the employee logs in to the server, payment for the document may be requested. For example, at least one or more documents to be paid may be output through the employee's electronic device. Employees can select documents for approval. Document approval may take place from at least one approver associated with the document. The approver can view the documents stored in the repository (1). For example, an approver can view a document for which an employee has requested approval. The approver can approve or reject the viewed document (2). For example, the approver may approve or reject by selecting a user interface (eg, a button) for approving or rejecting, as the approver checks the viewed document. The FIDO authentication process may be performed between the server and the approver (3). For example, the server may encrypt the document and transmit it to the approver as the document is approved or rejected by the approver, and the approver may respond to the server by digitally signing the encrypted document. The server may generate a DID certificate based on data acquired through the FIDO authentication process and store it in the storage (4). For example, the DID certificate for an approved document can be stored as follows.

11 is a diagram for describing a sequential approval operation according to an approval line in an authentication system according to an embodiment. In FIG. 11, it is for explaining a case where a plurality of approvers exist, and for convenience of description, two approvers will be described as an example. The first approver who approves the document will be described as the first approver, and the approver who approves after the first approver is the subsequent approver. When a document is to be approved by a plurality of approvers, a hash chain is generated based on metadata including a hash value generated from a first approver and information of a second approver, and the document can be approved. Through this hash chain, it can be verified that the approval of the approver has been made in the order specified in the approval line of the received document.

As the first approver verifies the document, an approval order can be entered. For example, it can be verified by reading a document through an electronic device related to the first approver. As the document is confirmed through an electronic device related to the first approver, a user interface (eg, a button) for inputting a command to approve or reject the document may be provided. The first approver can input approval or rejection through the user interface. An approval button for the document can be selected from the first approver (1). The server can hash the document ( H ₀ =Hash( Docs )).

The server may request FIDO authentication from the initial approver. Specifically, the server may generate meta data using whether or not to approve the document, the approved approval time, and the approver's identification information ( M ₁ = approval or not + approval time + approver ID). The server can generate a hash value using the hashed document and metadata ( H ₁ =Hash( H ₀ + M ₁ )), and can request FIDO authentication for the generated hash value to the first approver (Challenge = H ₁ )(2). It is possible to receive that the digital signature for the hash value generated using the FIDO authenticator is transmitted from the first approver (Response= S ₁ =Sign( H ₁ )). In other words, the initial approver can present FIDO certification (3).

An approval button for the document can be selected from a subsequent approver (4). The server can generate metadata using the approval status of the document, the approved approval time, and the approver's identification information ( M ₂ = approval status + approval time + approver ID). The server can generate a hash value using the document's metadata ( H ₂ =Hash ( H ₁ + M ₂ ), and can request FIDO authentication for the generated hash value to a subsequent approver (Challenge= H ₂ ). (5) It is possible to receive the digital signature of the hash value generated using the FIDO authenticator from the subsequent approver (Response= S ₂ =Sign( H ₂ )) In other words, the first approver presents the FIDO certification. (6) The server can store documents (Docs), metadata ( M ₁ , M ₂ ), and electronic signatures ( S ₁ , S ₂ ).

The authentication system according to an embodiment may apply a FIDO authentication protocol to an electronic signature for a document. The authentication system can provide integrity verification and non-repudiation functions in a standard way based on asymmetric encryption. The authentication system can use the service in any environment such as PC, authentication token, mobile, etc., and can be provided to use a convenient authentication method such as biometric authentication. The authentication system can minimize the installation of additional programs or hardware introduction to the user. The authentication system can improve compatibility and safety by managing the FIDO authenticator based on distributed ID.

The apparatus described above may be implemented as a hardware component, a software component, and/or a combination of a hardware component and a software component. For example, the devices and components described in the embodiments are, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA). , A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions, such as one or more general purpose computers or special purpose computers. The processing device may execute an operating system (OS) and one or more software applications executed on the operating system. In addition, the processing device may access, store, manipulate, process, and generate data in response to the execution of software. For the convenience of understanding, although it is sometimes described that one processing device is used, one of ordinary skill in the art, the processing device is a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that it may include. For example, the processing device may include a plurality of processors or one processor and one controller. In addition, other processing configurations are possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of these, configuring the processing unit to behave as desired or processed independently or collectively. You can command the device. Software and/or data may be interpreted by a processing device or to provide instructions or data to a processing device, of any type of machine, component, physical device, virtual equipment, computer storage medium or device. Can be embodyed. The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -A hardware device specially configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of the program instructions include not only machine language codes such as those produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like.

As described above, although the embodiments have been described by the limited embodiments and drawings, various modifications and variations are possible from the above description by those of ordinary skill in the art. For example, the described techniques are performed in a different order from the described method, and/or components such as a system, structure, device, circuit, etc. described are combined or combined in a form different from the described method, Alternatively, even if substituted or substituted by an equivalent, an appropriate result can be achieved.

Therefore, other implementations, other embodiments, and claims and equivalents fall within the scope of the claims to be described later.

Claims (6)

In the method of providing an identification card performed in an authentication server,
Configuring a distributed identity verification environment for managing authentication devices based on distributed ID;
Registering a user using an authentication device associated with an electronic device of a user whose identity has been verified in the configured distributed identification environment;
Receiving a request for payment of a document from the registered user; And
Approving the document through an electronic signature using an authentication device associated with the electronic device of the counterpart user as the document is viewed by the counterpart user
How to provide identification, including. The method of claim 1,
The step of configuring the distributed identification environment,
Issuing a distributed ID-based identification card to the user; And
Verifying the issued distributed ID-based identification card
Including,
Issuing a distributed ID-based identification card to the user,
As the user's identity is verified face-to-face or non-face-to-face by the issuer, a DID document is created using the user's public key obtained through the FIDO registration process using a FIDO authenticator, stored in the blockchain, and the user's DID identifier And issuing the determined user's DID identifier to the user, generating a DID certificate (Verifiable claim) using the user's identification information and the user's DID identifier, and storing it in the blockchain. step
How to provide identification, including. The method of claim 2,
The step of verifying the issued distributed ID-based identification card,
As the user's DID identifier is presented to the verifier from the user, the FIDO authentication process is performed using a FIDO authenticator, and the verifier searches the DID document and DID certificate in the blockchain using the DID identifier presented by the user. Verifying whether the public key used in the FIDO authentication process matches the public key existing in the DID document, and verifying the user's distributed ID-based identification card by checking the digital signature of the issuer existing in the DID certificate.
How to provide identification, including. The method of claim 1,
The step of registering the user,
As the user's identity is verified, a DID value for the user is issued through the user's FIDO registration process, and a DID document is created using the user's public key verified through the FIDO registration process and stored in the blockchain. And storing the DID certificate generated using the user's DID value and the identity information obtained through the user's identity verification in the blockchain.
How to provide identification, including. The method of claim 1,
The step of approving the document,
The step of generating a DID certificate based on the electronic signature verified through the FIDO authentication process with the counterpart user and storing the DID certificate on the basis of the electronic signature confirmed through the FIDO authentication process with the counterpart user as the document is approved or rejected as the document requested for payment is read
How to provide identification, including. The method of claim 5,
The step of approving the document,
When the document requested for approval is to be approved by a plurality of counterpart users, the document is hashed as the document is confirmed by the first counterparty user, and whether the document requested for approval is approved by the first counterparty user, and the approval request Metadata is generated using the approval time of the approved document and the identification information of the first counterpart user, and FIDO authentication is provided to the first counterpart user for the hash value generated using the hashed document and the metadata. Upon request, receiving from the first counterpart user that the digital signature for the generated first hash value is transmitted using a FIDO authenticator
As the document is confirmed by the second counterpart user, metadata is determined using whether the document requested for approval from the second counterpart user is approved, the approval time at which the document requested for payment is approved, and the identification information of the second counterpart user. And generates a second hash value using a hash value generated from the first counterpart user and metadata generated by the second counterpart user, and provides the second counterpart user with respect to the generated second hash value. Receiving that a digital signature for the generated second hash value is transmitted from the second counterpart user using a FIDO authenticator in response to requesting FIDO authentication
How to provide identification, including.

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