Blockchain-implemented methods and systems

Abstract

The invention provides a novel and advantageous solution for controlling or influencing the use and / or access of a resource. The resource can be a device, such as an IoT (Internet of Things) device or a process. The invention is implemented by means of a distributed ledger (blockchain). In an illustrative embodiment, the controlled resource is a parking meter. The invention can provide a method comprising the steps of: generating a blockchain transaction (Tx) indicative of a condition for use of the resource, the blockchain transaction comprising a multi-signature script requiring a plurality of signatures to complete the blockchain transaction; providing a first subset of the plurality of signatures to the blockchain transaction to generate a partially signed signature script to partially complete the blockchain transaction; and in response to the condition for use of the resource being met, providing a second subset of the plurality of signatures to the blockchain transaction to fully complete the blockchain transaction. The condition for use of the resource can be use of a discrete quantity of the resource, and the second subset of the plurality of signatures is provided in response to the discrete quantity of the resource used.

Description

[0001] This application is a divisional application of PCT National Stage application No. 201780042620.3, filed July 21, 2017, entitled "Method and System for Blockchain Implementation", which claims priority to U.S. Provisional Patent Application No. 62 / 447, 1 10, filed January 17, 2017, entitled "Method and System for Blockchain Implementation". TECHNICAL FIELD

[0002] The present invention relates generally to Distributed Ledger Technologies (DLTs), and in particular to controlling the use of resources using a blockchain. Aspects of the invention also relate to the Internet of Things (loT). The invention can be applicable to controlling loT devices.

[0003] In this document, we use the term "blockchain" for convenience and ease of reference, as it is the most widely known term in this field at present. This term as used herein includes all forms of electronic, computer-based, distributed ledgers, including consensus-based blockchains, alternative chains, sidechains and transaction chain technologies, private or public ledgers, permissioned and un-permissioned ledgers, shared ledgers and variations thereof. BACKGROUND

[0004] A blockchain is an electronic ledger, which is a computer-based, decentralised, distributed system that maintains a continuously growing list of records (blocks) linked using cryptography. Each block contains a hash of the previous block, creating a chain of data that is resistant to tampering. The blockchain contains all transactions that have been written into it since its inception. Transactions contain small programs, known as scripts, embedded in their inputs and outputs, which specify how and by whom the outputs can be accessed.

[0005] In order to write a transaction to the blockchain, it must be: i) "validated" by a first node that receives the transaction - if the transaction is valid, the node transmits the transaction to other nodes in the network; ii) added to a new block; and iii) mined, i.e. added to the public ledger of past transactions.

[0006] One area of current interest and research is the use of blockchains to implement "smart contracts". These are computer programs designed to automatically execute the terms of a contract or agreement. Unlike traditional contracts, which are written in natural language, smart contracts are machine-executable programs that include rules that can process inputs to produce results, which can then cause actions to be performed based on those results.

[0007] The invention also relates to a blockchain-implemented mechanism for controlling access to a resource. The resource can be a physical resource, for example an "Internet of Things (IoT)" device. The Internet of Things is described in Wikipedia as "a network of physical devices, vehicles, buildings and other items embedded with electronics, software, sensors, actuators, and network connectivity that enables these objects to collect and exchange data... The Internet of Things allows objects to be sensed and controlled remotely across existing network infrastructures". In other embodiments, the resource can be a non-physical resource, for example a network or software, some encrypted digital currency or any other form of asset. SUMMARY

[0008] The invention is defined in the appended claims.

[0009] The invention provides a computer-implemented method and corresponding system. The invention can provide a blockchain-implemented control method. The method can be used to enable, influence, manage or control usage and / or access to a resource. The resource can be an Internet-enabled resource, can be an IoT (Internet of Things) resource, can be a physical resource such as a device or apparatus or process, and can be a computer-based resource such as a network or software.

[0010] The method comprises the steps of:

[0011] generating a blockchain transaction (TxA) indicative of a condition for usage of the resource. The blockchain transaction can comprise a multi-signature script requiring a plurality of (digital) signatures to complete the blockchain transaction; and / or

[0012] providing a first subset of the plurality of signatures to the blockchain transaction to generate a partially signed signature script to partially complete the blockchain transaction; and / or

[0013] in response to the condition for usage of the resource being met, providing a second subset of the plurality of signatures to the blockchain transaction to fully complete the blockchain transaction (TxA).

[0014] By this method, the following advantages are provided: usage / access to the resource can be securely performed and immutably recorded. For ease of reading, we will simply refer to "usage" of the resource below, without repeating the term "and / or access".

[0015] The condition for usage of the resource can be usage of a discrete quantity of the resource, and the second subset of the plurality of signatures can be provided in response to the discrete quantity of the resource being used. The condition for usage of the resource can be specified or defined in a smart contract. The smart contract can be stored off-chain, but can be referenced from the blockchain, for example using metadata provided within a transaction.

[0016] This provides the advantage that the resource can be used or consumed incrementally.

[0017] If the condition for using / accessing the resource is not met: access or use of the resource can be prohibited or changed or limited; and / or an alert or notification can be sent to a destination.

[0018] A plurality of transactions can be generated. These transactions can be partially signed transactions, can be multi-signature transactions. Providing the second subset of signatures to the transaction TxA to complete the final step of the transaction TxA can comprise: selecting a transaction (TxA) from the plurality of transactions. Each of the plurality of transactions can be usable to spend the same output of a previous transaction (TX1). (“Previous” means that the transaction including the output is prior to the plurality of transactions on the blockchain). Thus, upon determining that the condition has been met, a transaction (TxA) can be selected and completed from the plurality of partially signed transactions. The selection and / or completion of the transaction can comprise providing the cryptographic key of the agent, and can be performed by the agent. The agent can be an automated resource suitably programmed. The agent can submit the selected transaction (TxA) to the blockchain network. By spending the transaction output (TX1 output) on the blockchain, validation of the transaction on the blockchain can cause an asset, for example a partially encrypted digital currency, to be transferred from one party to another.

[0019] Each of the plurality of transactions can indicate a different condition relating to the use of the resource. Thus, the plurality of transactions can implement a plurality of conditions (or scenarios) relating to the use of the resource. The invention controls how the output of the transaction (TX1) is spent and how the encrypted digital currency associated with the output is transferred by selecting the transaction to be completed and submitted.

[0020] Whether the condition is met can be assessed by the agent using an input or signal to determine said condition. The input or signal can be generated by the agent, or can be received from another source. The input or signal can be, for example, detection of a physical or electronic state, a point in time, or any other input.

[0021] Generating a blockchain transaction indicating a condition for use of a resource can comprise generating a blockchain transaction corresponding to each integer multiple of a discrete amount of the resource, and can provide a second subset of signatures to use each increasing integer multiple of the resource.

[0022] This provides the advantage of providing a range of possible use options, increasing the versatility of the method, for example, which parts of the network to use or the amount of network usage, or the length of time to use a resource such as a parking space, a device, etc.

[0023] A maximum limit on the integer multiples can be predefined.

[0024] This provides the advantage of allowing consequences to be implied and enforced as a result of overuse of the resource.

[0025] The dechunk action can be generated in response to an excess number of excesses over a maximum limit. The term "dechunk" can be interpreted as "not through the blockchain".

[0026] This provides the advantage of providing a consequence due to overuse of resources to be performed.

[0027] The first subset of the plurality of signatures can comprise a signature of an agent. The agent can be a computing-based resource.

[0028] This provides the advantage of increasing the security of the method.

[0029] The first subset of the plurality of signatures can comprise a signature of an issuer or owner or controller of the resource.

[0030] The second subset of the plurality of signatures can comprise a signature of an agent.

[0031] The second subset of the plurality of signatures can comprise a signature of a user of the resource.

[0032] This provides the advantage of preventing the issuer or user from abusing the method.

[0033] The condition for using the resource can be that a zero amount of the resource has been used.

[0034] This provides the advantage of defining a condition for a refund.

[0035] The blockchain transaction can have a non-zero lock time.

[0036] This provides the advantage of preventing the user from abusing the method.

[0037] The present invention can also provide a system comprising a computer-based resource for performing a method according to any embodiment of the method described herein. Any feature mentioned in relation to one aspect or embodiment of the present invention can also apply to any other aspect or embodiment. Any feature mentioned in relation to the method can apply to the system of the present invention and vice versa. Embodiments of the present invention can essentially be arranged in the following way.

[0038] These and other aspects of the present invention will become clear from the embodiments described herein. BRIEF DESCRIPTION OF DRAWINGS

[0039] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0040] Figure 1 a is a schematic diagram of a system according to the embodiment;

[0041] Figure 1 b is a flow diagram illustrating how a customer sets up a series of blockchain transactions to pay for parking using the system;

[0042] Figure 2 is a transaction in which Alice pays for parking at the initial stage;

[0043] Figure 3 is a transaction generated by the agent and sent to Bob for signature before the agent signs it, and the parking space has been used for 10 minutes before the agent signs.

[0044] Figure 4a and 4b different scenarios relating to the use of a parking space are schematically illustrated; and

[0045] Figure 5 is a transaction generated by the agent, which is signed by the agent and sent to Alice when no additional time is used. DETAILED DESCRIPTION

[0046] Overview

[0047] The present invention provides a new technique that allows the use and / or access to a controlled resource, or manages access / use to a resource, by using multiple blockchain transactions that implement different use / access scenarios related to the use or access. For example, a transaction related to the use of a resource for a specified period of time, and another transaction related to the use of a resource for a different period of time.

[0048] A user (i.e. a person accessing or using a resource) makes an intentional "double spend" attempt on the blockchain. A "double spend" occurs when a user is able to spend the same portion of a cryptographic digital currency twice, as is known in the art. Clearly, a double spend is undesirable in a conventional context, as at least one party is placed at a disadvantage by not receiving the funds they are owed or entitled to. The present invention therefore takes an approach that is conventionally undesirable, and uses it for the purpose of authorization to gain a benefit.

[0049] According to the present invention, a resource user provides an asset to a resource controller. This asset can be a portion of a cryptographic digital currency. The amount of the asset is determined by a set of conditional rules, which are typically defined in a smart contract. A smart contract is a machine executable document implemented by a blockchain, which can be stored off-chain and referenced by a blockchain transaction (Tx). The conditional rules can include various rules, criteria and parameters, among others. These rules, criteria and parameters, among others, govern or define authorized, legitimate use / access to a resource. In a preferred embodiment, these conditional rules are evaluated by an independent party (i.e. a party other than the resource user or controller).

[0050] Thus, advantageously, the resource controller determines that the condition will be met without having to know the details of how the condition will be met, as these will be determined and implemented by an independent party. The independent party can be an automated agent, which can be referred to as an oracle. The oracle determines the fulfilment of the condition based on an evaluation performed. This can be when the use / release / access to the resource is allowed, or at a predetermined time, or when a trigger event is detected, etc. The evaluation enables the oracle to select one proposed blockchain transaction to be completed. This is achieved by providing the selected transaction with an encrypted signature of the oracle. Thus, there is an external oracle that evaluates the conditions provided by the smart contract and determines which of a number of presented transactions (Tx) to complete based on parameters related to the use / access, e.g. how long the resource has been used, and then automatically invalidates the other proposed transactions.

[0051] If the oracle or agent determines that the condition is not met, the oracle and / or resource controller can take a responsive step, e.g. the use / access to the resource can be denied, a lock mechanism can be applied or configured, or a communication (e.g. an alert) can be sent to the recipient, and / or a refund transaction can be submitted to the blockchain network.

[0052] Explanatory use examples

[0053] We describe the system in terms of an example of using a parking space, where payment is required when a car is parked on the parking space. The relevant parking space owner (an existing parking space operator or small business or individual who owns available and desired parking spaces) attaches an IOT device 104 to the parking space. However, the invention is not limited to use with parking meters, other types of controlled internet resources can also be used in the invention.

[0054] The IOT device 104 is able to detect the presence of a parked vehicle (this is already a common practice). The device can be a blockchain IOT device 106, or part of 106. A programmable "blockchain IOT device (BID)" is an internet-enabled device that is also able to monitor, interact with, and publish to a blockchain network.

[0055] The vehicle driver downloads a smartphone application (or "smart car" application - i.e. an application designed to run on a car computer) that is compatible with the parking lot BID 106. The application allows the driver to pay for the parking space fee via the blockchain using a cryptographic digital currency.

[0056] The parking service can be represented using a smart contract, which is a machine-readable and executable document. The terms and conditions in the contract are referenced using metadata in transactions (Txs) that point to the location of the contract file on the DHT. In other embodiments, the contract can be stored in any other form of database or storage. The terms and conditions specified in the contract can include the following:

[0057] • Vehicle ID (e.g. license plate);

[0058] • Start time of parking;

[0059] • End time;

[0060] • Parking spot identifier (e.g. exact GPS location, or residential address, or address + number (can also be drawn on the actual parking spot or physical location of the parking spot);

[0061] • Rate (e.g. can be expressed in satoshis / minute, or $ / minute, etc.);

[0062] • Other complex conditions, e.g.

[0063] First 2 hours (or other period) free,

[0064] Partial period fee (e.g. "0.01 units of crypto currency per hour or a fraction of an hour").

[0065] In some embodiments, the BID 106 is able to identify the vehicle through one of several methods, for example the BID 106 can include a built-in camera that aims at the general area of the vehicle license plate; in another example, the BID 106 detects a unique signal ID emitted by the vehicle, in another example, a dedicated on-board tag RFID is attached to the vehicle. In some embodiments, (e.g. for privacy purposes) the BID 106 is not able to identify the vehicle, but rather the parking attendant is able to verify that the correct vehicle is parked by visually inspecting the license plate, comparing it to the license plate registered in the payment transaction.

[0066] The application can allow performing a range of functions, for example:

[0067] • The driver can book a parking spot, for a period of time,

[0068] The booking can or can not require prepayment;

[0069] • If the paid time expires, the driver can set the application to automatically pay and restart another period of time (adjustable);

[0070] • The application can allow for periodic parking (e.g. booking for weekdays).

[0071] As Figure 1 a shown, the system 100 includes a parking space 102, an internet enabled (Internet of Things or "IoT") device 104, a blockchain internet of things device (BID) 106, a blockchain server 108. The blockchain server 108 can be operative to provide access to a peer-to-peer network supporting a blockchain, and an agent 110 operative to monitor the blockchain and communicate with the IoT device 104 and the BID 106.

[0072] Now, we describe the use of the parking space using the system 100 with reference to the flowchart in Figure 1 b Alice has a smartphone app that queries the blockchain to indicate the location of available parking spaces. In step S100, Alice finds a convenient parking space and parks her car. The app displays the terms and conditions of the parking space, for example, a residential driveway in a dense downtown location in London or Los Angeles.

[0073] In step S102, Alice accepts the terms and conditions, and after selecting certain options, uses the app to pay for the parking space for the required time. She is not entirely sure that she will be back in time, so she also selects the auto-renewal option offered by the app, which extends the parking time by 10 minutes each time it comes up to time, up to 3 times (although she thinks this extra cost is a bit steep, she is willing to pay it because it avoids the penalty and damage to her reputation of being late).

[0074] Of course, Alice knows that the smartphone app offers the option to extend the time remotely just before it comes up to time, but because she will be at a meeting, she does not know if she will have this opportunity. Later, Alice returns before the termination time. Although the smartphone app allows her to cancel the extension of time that she no longer needs, she knows that she does not need to do this because the BID 106 operator has set it up so that she just needs to leave and the BID 106 will detect that she has not used the extension of time and so (according to the contract) automatically cancel the extension of time for her.

[0075] So, we assume that Alice rents the parking space for 1 hour with 5 units of the crypto-currency, and the extra time costs 1 unit of the crypto-currency per 10 minutes.

[0076] The first transaction to credit Bob with 5 units of the crypto-currency is a P2PKH payment for the first hour.

[0077] We define T extra as the time that Alice's car is parked in the parking space after the standard period of time (i.e. after the first hour that has been paid for).

[0078] T extra is a multiple of 10, taking values 0, 10, 20, 30. At times T = 60, 70, 80 and 90 minutes, the BID 106 checks whether the vehicle is still parked in the parking spot. If not, the BID 106 sends a message to Alice, Bob (the parking spot owner) and a third party (or "proxy"). The message contains the value T extra . For example, if Alice returns to the parking spot at 65 minutes, T extra = 10, and Bob should charge Alice 1 unit of the cryptographic digital currency. However, Alice does not trust Bob, she would rather use an independent service to let go of the funds, and this letting go should be conditioned on the signature of a proxy server. The proxy accepts the request, e.g. T extra = 10?, evaluates the request and generates an output. The proxy receives this information from the IoT device 104.

[0079] Alice and Bob agree on a rules script and send it to the proxy server (01). The script can be as follows:

[0080] If (T extra == 10) return Sign TxA

[0081] else if (T extra == 20)

[0082]

[0083] If 01 has parsed the script favorably, i.e. one of the conditions for using the parking spot is met, 01 signs and broadcasts TxAor TxBor TxC(not all).

[0084] In step S104, the proxy generates a new public key. In step S106, the proxy obtains the public keys from Alice and Bob. Then, in step S108, the proxy generates a 2 / 3 multisignature address.

[0085] Alice generates a new transaction Tx1, which sends 3 units of the cryptographic digital currency to the multisignature address in step S110, signs Tx1 and broadcasts it on the network. The transaction is as shown in Figure 2 .

[0086] The proxy validates Tx1 and generates in step S112 three transactions spending the UTXO of Tx1. The three transactions can be denoted as TxA, TxBand TxC. The proxy also generates in step S112 a fourth transaction TxR. TxAis as shown in Figure 3 . TxBand TxCare similar, but for different amounts of the cryptographic digital currency, as described below.

[0087] From Figure 3 it can be seen that TxA sends 1 unit of encrypted digital currency to Bob and 2 units of encrypted digital currency to Alice, corresponding to T extra = 10. TxB sends 2 units of encrypted digital currency to Bob and 1 unit of encrypted digital currency to Alice, corresponding to T extra = 20. TxC sends 3 units of encrypted digital currency to Bob, corresponding to T extra = 30.

[0088] Each of TxA, TxB and TxC requires 2 signatures, namely a signature by Bob and a proxy signature. In step S114, the proxy sends TxA, TxB and TxC to Bob. Bob then signs each of TxA, TxB and TxC in step S116 and returns them to the proxy as incomplete blockchain transactions.

[0089] TxR is a refund transaction that sends 3 units of encrypted digital currency back to Alice; it has a non-zero lock time corresponding to some future time. TxR requires two signatures, namely a signature by Alice and a signature by the proxy. That is, if Alice does not use the parking spot for some time within the time paid for in Tx1, then there is an automatic refund. In step S112, the proxy signs TxR at the time of its generation. TxR is as shown in Figure 5 .

[0090] Now we consider this example: Alice parks in the parking spot for a maximum of 10 minutes after the 1 hour paid for in Tx1, i.e. T extra = 10, referring to Figure 4a .

[0091] In step S200, the IoT device 104 detects that Alice’s car has been parked in the spot for more than 1 hour paid for in Tx1, for more than 10 minutes. Then, in step S202, the BID 106 sends the information that the car has been parked in the spot for more than 10 minutes to the proxy, i.e. T extra = 10. That is, one of the conditions in the script above has been evaluated as true by the proxy.

[0092] Then, in step S204, the proxy signs TxA to complete the transaction. Then, in step S206, TxA can be broadcast to the blockchain. Completing TxA pays 1 unit of encrypted digital currency to Bob and 2 units of encrypted digital currency to Alice. TxB and TxC can be similarly completed.

[0093] Now we consider this example: Alice leaves the parking spot on time, Textra = 0, reference Figure 4b will be described. In step S300, the IoT device 104 detects that Alice has moved her car from the parking spot without exceeding the reservation time. In step S302, the IoT device 104 sends a message to the agent that Alice has left the spot on time. In step S304, the IoT device 104 sends TxR to Alice who signs it to complete the transaction TxR. The completion of the transaction TxR means that the 3 units of the cryptographic digital currency are returned to Alice. TxR has a non-zero lock time, which means that it can not be mined and added to the blockchain until the lock time expires. This means that if Alice provides the signature, TxR will be broadcast at some point in the future rather than immediately.

[0094] It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that one skilled in the art will be able to devise many alternative embodiments without departing from the scope of the application as defined by the following claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The words "comprising" and "comprises" and the like do not exclude the presence of elements or steps other than those listed in any claim or the specification as a whole. In the present specification, "comprising" means "including or consisting of" and "comprises" means "including or consisting of". The singular references "a", "an" and "the" should not be construed as excluding the plural reference unless the context clearly indicates so. The application can be implemented by means of both hardware and software, and any different embodiments of the application can be implemented by means of hardware or software. In the device claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The mere fact that several elements are recited in mutually different dependent claims does not indicate that these elements cannot be used in combination.

Claims

1. A computer-implemented apparatus for controlling the use and / or access to resources, the apparatus comprising: A generation module is used to generate blockchain transactions, which indicate the following conditions: using the resources within a specified time period; the blockchain transaction includes a multi-signature script that requires multiple signatures to complete the blockchain transaction. The specified time period is provided in the smart contract; and the smart contract is referenced using metadata from the blockchain transaction. A module is provided to provide a first subset of the multiple signatures to the blockchain transaction to generate a signature script for partially signing, thereby partially completing the blockchain transaction; The selection module, in response to the fulfillment of resource usage / access conditions, provides a second subset of the multiple signatures to the selected blockchain transaction to fully complete the blockchain transaction.

2. The computer-implemented apparatus according to claim 1, wherein, The condition associated with using resources is that a discrete amount of resources are used, and a second subset of the plurality of signatures is provided in response to the discrete amount of resources used.

3. The computer-implemented apparatus according to claim 2, wherein, The generation module is also used to generate blockchain transactions corresponding to each integer multiple of the discrete amount of resources, and to provide a second subset of the multiple signatures to use each additional integer multiple of resources.

4. The computer-implemented apparatus according to claim 3, wherein, The maximum limit for the integer multiples has been predefined.

5. The computer-implemented apparatus according to claim 4, wherein, In response to an exceedance exceeding the maximum limit, a deblocking action is generated.

6. The computer-implemented apparatus according to claim 1, wherein, The first subset of the multiple signatures includes the agent's signature.

7. The computer-implemented apparatus according to claim 1, wherein, The first subset of the multiple signatures includes the signature of the issuer of the resource.

8. The computer-implemented apparatus according to claim 7, wherein, The second subset of the multiple signatures includes the agent's signature.

9. The computer-implemented apparatus according to claim 6, wherein, The second subset of the multiple signatures includes the signatures of the user of the resource.

10. The computer-implemented apparatus according to claim 1, wherein, The condition for using or accessing the resource is that zero of the resource has already been used.

11. The computer-implemented apparatus according to claim 1, wherein, The blockchain transactions have a non-zero lock-in time.

12. The computer-implemented apparatus according to claim 1, further comprising: The submission module is used to submit the fully completed blockchain transaction to the blockchain to spend the output of the previous transaction (Tx1).

13. The computer-implemented apparatus according to claim 1, wherein, The resources mentioned are physical resources, Internet-enabled resources, or Internet of Things (IoT) devices.

14. A computing device, comprising: processor; as well as Memory for storing instructions executable by the processor. The processor is configured to execute instructions stored in the memory to perform a method for controlling the use and / or access to resources in a blockchain implementation, the method comprising the following steps: A blockchain transaction is generated, the blockchain transaction indicating the following conditions: use of the resource within a specified time period; the blockchain transaction includes a multi-signature script that requires multiple signatures to complete the blockchain transaction; wherein the specified time period is provided in a smart contract; and wherein the smart contract is referenced using metadata in the blockchain transaction; Provide a first subset of the multiple signatures to the blockchain transaction to generate a signature script for partially signed transactions, thereby partially completing the blockchain transaction; In response to the fulfillment of the conditions for resource use / access, a second subset of the multiple signatures is provided to the selected blockchain transaction to fully complete the blockchain transaction.

15. A computer-readable storage medium having a computer program stored thereon, the computer program, when executed by a computer, causing the computer to perform a method for controlling the use and / or access to resources implemented in a blockchain, the method comprising the steps of: A blockchain transaction is generated, indicating the following conditions: the resource is used within a specified time period; the blockchain transaction includes a multi-signature script that requires multiple signatures to complete the blockchain transaction. The specified time period is provided in the smart contract; and the smart contract is referenced using metadata from the blockchain transaction. Provide a first subset of the multiple signatures to the blockchain transaction to generate a signature script for partially signed transactions, thereby partially completing the blockchain transaction; In response to the fulfillment of the conditions for resource use / access, a second subset of the multiple signatures is provided to the selected blockchain transaction to fully complete the selected blockchain transaction.

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