Blockchain block packaging method, system and electronic device suitable for the Internet of Things

Abstract

The present invention relates to the field of blockchain technology, and discloses a blockchain block packaging method, system and electronic device suitable for the Internet of Things, including: sending transaction data to node X, node X verifies the transaction data, and after successful verification, the transaction data is packaged to form block N+1; node X verifies the previous block N of block N+1 and selects a random block M before block N as the endorsement block of block N+1, determines the output node Y corresponding to block M as the endorsement node of block N+1 according to block M, and node Y verifies the legitimacy of block N+1; after both block N and block N+1 are successfully verified, the information of block N and block M is written into block N+1, and block N+1 becomes the latest block formed in the blockchain. The present invention greatly reduces the packaging time, not only improves the block efficiency, but also ensures its data reliability, and is more suitable for the Internet of Things.

Description

Technical Field

[0001] The present invention relates to the field of blockchain technology, and specifically to a blockchain block packaging method, system and electronic device suitable for the Internet of Things. Background Art

[0002] The Internet of Things system is a set of software and hardware systems including terminal devices, communication units, and server-side systems, which provide services for people's production and life. The large amount of Internet of Things data it sends, such as environmental temperature and humidity, storage information, consumption amount, hardware status, etc., should be true and reliable, and the data in the system should be protected from theft and tampering. For this reason, some technical solutions have integrated blockchain with the Internet of Things to ensure the security, reliability, and traceability of system data; but due to the system characteristics of blockchain, it is impossible to complete real-time response to data. For example, after the operator issues a device control instruction or the user purchases a product, it may take more than ten seconds for the system to respond, which cannot meet the efficiency issues of daily production and life.

[0003] Therefore, there is an urgent need for a new blockchain system that is suitable for the Internet of Things and can improve efficiency while taking security into consideration. Summary of the invention

[0004] The purpose of the present invention is to overcome the problem of long response time of the existing Internet of Things blockchain system, and to provide a blockchain block packaging method, system and electronic device suitable for the Internet of Things.

[0005] In order to achieve the above object, the present invention provides a blockchain block packaging method suitable for the Internet of Things, comprising the following steps:

[0006] Obtain transaction data sent by the IoT device, and send the transaction data to node X. Node X verifies the received transaction data, and after successful verification, packages the transaction data to form block N+1;

[0007] The node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1. According to the block M, the output node Y corresponding to the block M is determined as the endorsement node of the block N+1. The node Y verifies the legitimacy of the block N+1.

[0008] After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

[0009] As an implementable method, it also includes: when the block N+1 is determined to be illegal by a subsequent node, confirming that the node Y that verifies the block N+1 is an abnormal node or an unreliable node, confirming that the block M produced by the node Y and all blocks formed thereafter are illegal, discarding the block M and all blocks formed thereafter, and subsequently repackaging the transaction data sent by the IoT device from block M-1.

[0010] As an implementable method, the step of determining the output node Y corresponding to the block M according to the block M includes:

[0011] The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

[0012] As an implementable method, the verification content of the node X verifying the previous block N of the block N+1 includes:

[0013] The node X calculates a hash value for the entire block N as a whole data, and compares it with the current block hash value in the block header of the block N; the node calculates a hash value for the block data of the block N as a whole data, and compares it with the block data hash value in the block header of the block N; the node X compares the obtained public key with the digital signature in the block header of the block N;

[0014] When the comparison results are inconsistent, the block N is determined to be illegal and the verification fails; when the comparison results are consistent, the block N is determined to be legal and the verification succeeds.

[0015] As an implementable method, the verification content of the node Y verifying the legitimacy of the block N+1 includes:

[0016] The node X sends the entire block N+1 to the node Y. The node Y calculates a hash value for the entire block N+1 as a whole data, and compares it with the current block hash value in the block header of the block N+1. The node Y calculates a hash value for the block data of the block N+1 as a whole data, and compares it with the block data hash value in the block header of the block N+1. The node Y compares the acquired public key with the digital signature in the block header of the block N+1.

[0017] When the comparison results are inconsistent, the block N+1 is determined to be illegal and the verification fails. When the comparison results are consistent, the block N+1 is determined to be legal and the verification succeeds.

[0018] Accordingly, the present invention also provides a blockchain block packaging system suitable for the Internet of Things, which is characterized by comprising the following modules:

[0019] Packaging module: obtains the transaction data sent by the IoT device, sends the transaction data to node X, and node X verifies the received transaction data. After successful verification, the transaction data is packaged to form block N+1;

[0020] Verification module: the node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1, and determines the output node Y corresponding to the block M as the endorsement node of the block N+1 according to the block M, and the node Y verifies the legitimacy of the block N+1;

[0021] Block formation module: After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

[0022] As an implementable method, it also includes: a block discarding module: when the block N+1 is determined to be illegal by a subsequent node, the node Y that verifies the block N+1 is confirmed to be an abnormal node or an unreliable node, and the block M produced by the node Y and all the blocks formed thereafter are confirmed to be illegal, and the block M and all the blocks formed thereafter are discarded, and the subsequent packaging starts from block M-1 to repack the transaction data sent by the IoT device.

[0023] As an implementable method, the step of determining the output node Y corresponding to the block M according to the block M includes:

[0024] The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

[0025] Correspondingly, the present invention also provides an electronic device, comprising: at least one processor, and a memory communicatively connected to at least one of the processors; at least one of the processors is used to read a program in the memory to execute the method.

[0026] Correspondingly, the present invention also provides a computer-readable storage medium, characterized in that instructions are stored on the medium, and when the instructions are executed on a computer, the computer executes the method.

[0027] Beneficial effects of the present invention: The present invention integrates the common nodes and packaging nodes in the prior art into one node, and starts packaging into blocks immediately after a piece of IoT transaction data is generated, thus saving the data packaging waiting time in the original system. The node is responsible for verifying transaction data, generating blocks, verifying other blocks, and putting the generated blocks into the blockchain. The data received by the improved IoT blockchain system is immediately processed, which not only improves the block efficiency, but also ensures its data reliability, making it more suitable for the IoT. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention is a flowchart of a blockchain block packaging method applicable to the Internet of Things.

[0029] Figure 2 This is a schematic diagram of the overall process of the blockchain block packaging method for the traditional Internet of Things.

[0030] Figure 3 The figure is a schematic diagram of the overall process of the blockchain block packaging method applicable to the Internet of Things of the present invention.

[0031] Figure 4 The present invention is a schematic diagram of the process of the blockchain block packaging method suitable for the Internet of Things, using the Internet of Things device sensor as the Internet of Things device. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] See also Figure 2 The flowchart of the IoT device data being packaged into blocks in the existing IoT blockchain system is as follows: first, the IoT device generates IoT data and sends it to the common node of the blockchain system, wherein the IoT device includes the device management station, the data monitoring room, the merchant cashier, the IoT device vending machine, the IoT device robot, the IoT device sensor, the IoT device mobile phone, etc.; the common node verifies the correctness of the IoT data, and after successful verification, adds the IoT data to the local transaction pool of the common node; then the IoT data is sent to the packaging node selected by the consensus algorithm and the IoT data is stored in the transaction pool of the packaging node. After a certain amount of IoT data is accumulated in the transaction pool of the packaging node selected by the consensus algorithm, the data is packaged and a new block is generated, such as Figure 2As shown, blocks J, ..., block M, ..., block N, block N+1 and block N+2 are packaged in sequence. Each block contains a certain number of IoT data. After packaging, the packaging node notifies the ordinary node of the packaging result, and the ordinary node updates the local transaction pool.

[0034] However, the existing IoT blockchain system introduced above has the following disadvantages: First, there are many participating links. Specifically, the system includes ordinary nodes and packaging nodes, which involve communication and information synchronization, which consumes time; second, the packaging time is long. The existing blockchain 1.0 adopts the POW consensus algorithm, which consumes a lot of computing resources to produce a block, and it takes about 10 minutes to produce a block; the existing blockchain 2.0, such as the blockchain using the POA consensus algorithm, takes about 14 seconds to produce a block, which is too time-consuming for the IoT field; third, the packaging process is long. From entering the system to becoming part of the block, IoT data involves multiple links and requires about 6 steps. Local processing and network communication in each link will consume time.

[0035] In this embodiment, the ordinary node and the packaging node are merged into one role, which is directly referred to as a node in this article. When an IoT transaction data is generated, it is immediately packaged into a block, which saves the data packaging waiting time in the original system. The node is responsible for verifying the transaction data, verifying the historical blocks, and packaging the new data into the blockchain. The data received by the improved IoT blockchain system is immediately processed.

[0036] See also Figure 1 , this embodiment provides a technical solution: a blockchain block packaging method suitable for the Internet of Things, comprising the following steps:

[0037] Step S100, acquiring transaction data sent by the IoT device, and sending the transaction data to node X, wherein node X verifies the received transaction data, and after successful verification, packages the transaction data to form block N+1;

[0038] Step S200, the node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1, and determines the output node Y corresponding to the block M as the endorsement node of the block N+1 according to the block M, and the node Y verifies the legitimacy of the block N+1;

[0039] Step S300: After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

[0040] In this embodiment, the value of N is greater than 1, and the node X refers to a certain node, but not a specific node.

[0041] For details, see Figure 3 The IoT devices include device management desks, data monitoring rooms, merchant cashier counters, IoT device vending machines, IoT device robots, IoT device sensors, IoT device mobile phones, etc., and may also be rail transit equipment, etc. Each time the IoT device generates a transaction data, it sends the transaction data to the node. Each time the node receives a transaction data, it packages it, and sequentially packages it to form blocks J, ..., block M, ..., block N, block N+1 and block N+2, wherein each block contains block header information and block data, and the block header information includes a block production node ID and digital signature, production time, a hash value of a previous block, a hash value of a randomly selected block before the previous block, a current block hash value, a block data hash value, and a data portion size, and the block data includes transaction data.

[0042] After the block N+1 is formed, when a new block N+2 is formed again, the node that produces block N+2 will choose to verify block N+1; or, when the block N+1 is randomly selected for verification, the legality of the block N+1 will be verified again; at this time, when the block N+1 is determined to be illegal by the subsequent nodes, the node Y that verifies the block N+1 is confirmed to be an abnormal node or an unreliable node, and the block M produced by the node Y and all the blocks formed thereafter are confirmed to be illegal, and the block M and all the blocks formed thereafter are discarded, and the subsequent packaging starts from block M-1 to re-pack the transaction data sent by the IoT device.

[0043] Specifically, when the block N+1 is confirmed to be illegal, since in the process of forming the block N+1, the output node Y of the block M verifies the block N+1 and confirms that it is legal, therefore, when the block N+1 is confirmed to be illegal, it indicates that the node Y verifying the block N+1 has an abnormality or the node Y is an unreliable node, and the corresponding block M will be confirmed to be illegal and kicked out of the node. Since the block M+1 will be verified to ensure the legality of the block M when it is generated, when the block M is illegal, the output node of the block M+1 that verifies the block M is also an abnormal or unreliable node, and the corresponding block M+1 will be confirmed to be illegal and kicked out of the node. By analogy, the block M and all subsequent data are unreliable data and need to be discarded. The data sent by the subsequent IoT device is packaged into a new block M after the block M-1.

[0044] Executing step S200, the step of determining the output node Y corresponding to the block M according to the block M includes:

[0045] The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

[0046] The verification content of the node X verifying the previous block N of the block N+1 includes:

[0047] The node X calculates a hash value for the entire block N as a whole data, and compares it with the current block hash value in the block header of the block N; the node calculates a hash value for the block data of the block N as a whole data, and compares it with the block data hash value in the block header of the block N; the node X compares the obtained public key with the digital signature in the block header of the block N;

[0048] When the comparison results are inconsistent, the block N is determined to be illegal and the verification fails; when the comparison results are consistent, the block N is determined to be legal and the verification succeeds.

[0049] The verification content of the node Y verifying the legitimacy of the block N+1 includes:

[0050] The node X sends the entire block N+1 to the node Y. The node Y calculates a hash value for the entire block N+1 as a whole data, and compares it with the current block hash value in the block header of the block N+1. The node Y calculates a hash value for the block data of the block N+1 as a whole data, and compares it with the block data hash value in the block header of the block N+1. The node Y compares the acquired public key with the digital signature in the block header of the block N+1.

[0051] When the comparison results are inconsistent, the block N+1 is determined to be illegal and the verification fails. When the comparison results are consistent, the block N+1 is determined to be legal and the verification succeeds.

[0052] It should be noted that there are many situations in which a block is judged to be illegal. For example, the overall calculated hash value of the current block is considered illegal when the result is inconsistent with the "current block Hash" recorded in the current block header; or, the nodes entering the system are all controlled by the system and cannot be accessed arbitrarily. After joining, the system will allocate a set of keys (public key + private key). The node uses the private key (not leakable) to generate a digital signature for the output block and put it in the block header. Other nodes use the public key (public) of the current output block node to verify the block. Illegal nodes cannot be found in the system and the public key cannot be issued, so the block cannot be verified; or, several fields in the block header, such as "output time" is less than the current time, and "block data hash value" is wrong, will determine that the block is illegal;

[0053] In this embodiment, the reason why the production node X of the block N+1 verifies the previous block N of the block N+1 is to ensure that the block N is legal.

[0054] In this embodiment, the node selects a random block M before the block N as the endorsement block of the block N+1, and determines the output node Y corresponding to the block M as the endorsement node of the block N+1 according to the block M. The reasons are: first, to ensure that each node has not only the ability to generate blocks after entering the system, but also the ability to verify the legitimacy of other blocks; second, since the node Y is selected on the basis of the random selection of block M, it means that the selection of the node Y also has a certain randomness within a certain range, so that all nodes in the system can participate in the verification of blocks, and the system is prevented from being monopolized by a certain node; if it is monopolized, it will produce a "dominant" phenomenon and arbitrarily forge data; in this embodiment, all nodes participating in the system obey a consensus, that is, they produce blocks themselves, and other nodes verify them to reach a fair consensus; finally, it should be noted that the position of the node Y selected forward can be dynamically adjusted or fixed.

[0055] Specifically, for example Figure 4As shown, the IoT device sensor sends transaction data to node X, and node X verifies the transaction data, including data integrity verification and data signature verification. After successful verification, it is packaged into block N+1. It can be seen that there are already blocks E, ..., J, ..., M, ..., and N in the system, and each block contains a transaction data. First, the output node X of block N+1 verifies the previous block N of block N+1, and the verification content includes the hash value of the entire block N, the hash value of the data stored in block N, and the digital signature of the output node of block N. Then, the output node X of block N+1 selects any block M formed before block N as the endorsement node, finds node Y according to the ID and digital signature of the output node stored in block M, and uses node Y as the endorsement block of block N+1. , the node X sends the block N+1 as a whole to the node Y, and the node Y verifies the legitimacy of the block N+1. The verification content includes the hash value of the block N+1 as a whole, the hash value of the data stored in the block N+1, and the digital signature of the output node of the block N+1. After the verification of the block N and the block N+1 is successful, the information of the block M and the block N is written into the block N+1, and the block N+1 becomes the latest block in the blockchain. When a new block N+2 is to be formed, the block N+1 can be selected for verification, and any block before the block N+1 and the output node of the selected block are selected as the endorsement block and the endorsement node respectively. For example, block J is selected, and the output node of the block J verifies the block N+2. After the verification is successful, a new block N+2 is formed again, and so on, so that the access node can be controlled.

[0056] In this embodiment, each block no longer needs to accumulate multiple transaction data before packaging. After receiving a transaction data, the node immediately starts to package it to generate a new block and add it to the system. The data received by the improved Internet of Things blockchain system is processed immediately, saving the transaction data packaging waiting time in the original system; at the same time, the system no longer needs a transaction pool as a cache area for transaction data, avoiding the risk of long-term storage of transaction data in the transaction pool without being processed.

[0057] The nodes of this embodiment are responsible for verifying transaction data, generating blocks, verifying other blocks, and putting the generated blocks into the blockchain, which not only improves the block efficiency, but also ensures the reliability of data in the system, and is more suitable for the Internet of Things.

[0058] This embodiment no longer uses the existing POW or POA algorithm of the blockchain. Each node adopts Kafka, a message function module suitable for the Internet of Things. Kafka is a high-throughput distributed publish-subscribe-consume module suitable for message processing and data synchronization between multiple systems. Through the distributed message processing mechanism of this module, newly generated blocks are shared within the system to complete "joint accounting". However, it should be noted that this method is only applicable to private chains or alliance chains controllable by access nodes, and ultimately achieves a technical effect of only requiring millisecond processing time and greatly reducing waiting time.

[0059] Based on the same inventive concept, an embodiment of the present invention also provides a blockchain block packaging system suitable for the Internet of Things, including the following modules:

[0060] Packaging module: obtains the transaction data sent by the IoT device, sends the transaction data to node X, and node X verifies the received transaction data. After successful verification, the transaction data is packaged to form block N+1;

[0061] Verification module: the node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1, and determines the output node Y corresponding to the block M as the endorsement node of the block N+1 according to the block M, and the node Y verifies the legitimacy of the block N+1;

[0062] Block formation module: After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

[0063] Also includes:

[0064] Block discard module: When the block N+1 is determined to be illegal by subsequent nodes, the node Y that verifies the block N+1 is confirmed to be an abnormal node or an unreliable node, and the block M produced by the node Y and all the blocks formed thereafter are confirmed to be illegal. The block M and all the blocks formed thereafter are discarded, and the subsequent packaging starts from block M-1 to repack the transaction data sent by the IoT device.

[0065] The step of determining the output node Y corresponding to the block M according to the block M includes:

[0066] The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

[0067] Based on the same inventive concept, an embodiment of the present invention also provides an electronic device. Regarding the components, please refer to the above-mentioned related descriptions, and the repeated parts will not be repeated here. It includes: at least one processor, and a memory communicatively connected to the at least one processor; the at least one processor is used to read the program in the memory to execute the method described above.

[0068] Based on the same inventive concept, an embodiment of the present invention further provides a computer-readable storage medium. Regarding the components, please refer to the above-mentioned related descriptions, and the repeated parts will not be repeated. Instructions are stored on the medium. When the instructions are executed on the computer, the computer executes the method described above.

[0069] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A blockchain block packaging method suitable for the Internet of Things, characterized in that: The following steps are involved: Obtain transaction data sent by the IoT device, and send the transaction data to node X. Node X verifies the received transaction data, and after successful verification, packages the transaction data to form block N+1; The node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1. According to the block M, the output node Y corresponding to the block M is determined as the endorsement node of the block N+1. The node Y verifies the legitimacy of the block N+1. After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

2. The blockchain block packaging method suitable for the Internet of Things according to claim 1 is characterized in that: Also includes: When the block N+1 is determined to be illegal by subsequent nodes, the node Y that verifies the block N+1 is confirmed to be an abnormal node or an unreliable node, and the block M produced by the node Y and all the blocks formed thereafter are confirmed to be illegal. The block M and all the blocks formed thereafter are discarded, and the subsequent packaging starts from block M-1 to repack the transaction data sent by the IoT device.

3. The blockchain block packaging method suitable for the Internet of Things according to claim 1 is characterized in that: The step of determining the output node Y corresponding to the block M according to the block M includes: The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

4. The blockchain block packaging method suitable for the Internet of Things according to claim 1 is characterized in that: The verification content of the node X verifying the previous block N of the block N+1 includes: The node X calculates a hash value for the entire block N as a whole data, and compares it with the current block hash value in the block header of the block N; the node X calculates a hash value for the block data of the block N as a whole data, and compares it with the block data hash value in the block header of the block N; the node X compares the obtained public key with the digital signature in the block header of the block N; When the comparison results are inconsistent, the block N is determined to be illegal and the verification fails; when the comparison results are consistent, the block N is determined to be legal and the verification succeeds.

5. The blockchain block packaging method suitable for the Internet of Things according to claim 1 is characterized in that: The verification content of the node Y verifying the legitimacy of the block N+1 includes: The node X sends the entire block N+1 to the node Y. The node Y calculates a hash value for the entire block N+1 as a whole data, and compares it with the current block hash value in the block header of the block N+1. The node Y calculates a hash value for the block data of the block N+1 as a whole data, and compares it with the block data hash value in the block header of the block N+1. The node Y compares the acquired public key with the digital signature in the block header of the block N+1. When the comparison results are inconsistent, the block N+1 is determined to be illegal and the verification fails. When the comparison results are consistent, the block N+1 is determined to be legal and the verification succeeds.

6. A blockchain block packaging system suitable for the Internet of Things, characterized in that: Includes the following modules: Packaging module: obtains the transaction data sent by the IoT device, sends the transaction data to node X, and node X verifies the received transaction data. After successful verification, the transaction data is packaged to form block N+1; Verification module: the node X verifies the previous block N of the block N+1 and selects a random block M before the block N as the endorsement block of the block N+1, and determines the output node Y corresponding to the block M as the endorsement node of the block N+1 according to the block M, and the node Y verifies the legitimacy of the block N+1; Block formation module: After both the block N and the block N+1 are successfully verified, the information of the block N and the block M is written into the block N+1, and the block N+1 becomes the latest block formed in the blockchain.

7. The blockchain block packaging system suitable for the Internet of Things according to claim 6 is characterized in that: Also includes: Block discard module: When the block N+1 is determined to be illegal by subsequent nodes, the node Y that verifies the block N+1 is confirmed to be an abnormal node or an unreliable node, and the block M produced by the node Y and all the blocks formed thereafter are confirmed to be illegal. The block M and all the blocks formed thereafter are discarded, and the subsequent packaging starts from block M-1 to repack the transaction data sent by the IoT device.

8. The blockchain block packaging system suitable for the Internet of Things according to claim 6 is characterized in that: The step of determining the output node Y corresponding to the block M according to the block M includes: The ID and digital signature of the output node in the block header of the block M are obtained, and the output node Y corresponding to the block M is determined according to the ID and digital signature of the output node.

9. An electronic device, characterized in that: include: at least one processor, and a memory communicatively coupled to at least one of the processors; At least one of the processors is used to read the program in the memory to execute the method as claimed in any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that: The medium stores instructions, and when the instructions are executed on a computer, the computer is enabled to execute the method according to any one of claims 1 to 5.

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