A blockchain-based ship log storage system

Abstract

The present invention relates to a blockchain-based ship logbook storage system, the system is built on a blockchain operating environment with ship networking, block propagation protocol and relationship network as network architecture; wherein the ship networking is used to support the transmission of application layer data between ships in a point-to-point or broadcast notification manner, the point being the ship in the ship networking; the digital identity of the ship and the crew is authenticated by a ship digital certificate and a crew digital certificate; the ship and the crew sign the information by the private key corresponding to the certificate, and the node in the ship networking verifies the authenticity and integrity of the information by the public key corresponding to the certificate; the block propagation protocol is established on the ship networking using blockchain, and the block propagation protocol is used to forward and propagate the ship logbook between ships in the form of blocks. The present invention ensures the authenticity and reliability of IoS information exchange, and realizes the non-tamperability and traceability of the ship logbook.

Description

Technical Field

[0001] The present invention relates to the field of ship networking and blockchain technology, and in particular to a blockchain-based ship logbook storage system. Background Art

[0002] In recent years, the cyber threats to maritime systems have become increasingly severe. This situation shows that information security has become an important piece of the puzzle in maritime security and will be the trend of maritime technology development. The Internet of Ships (IoS) carries the transmission and exchange of maritime information. Building a reliable and trustworthy IoS is a rigid requirement for ensuring maritime information security. Compared with the mature Internet, the operation of IoS faces several major information security challenges. First, there is no unified identification system for the digital identity of IoS entities (especially ships); second, IoS lacks information authentication and traceability mechanisms; third, there is a lack of trusted computing environment between IoS system entities. Therefore, the issue of ensuring the authenticity and credibility of information has become a major challenge for data exchange in IoS.

[0003] In the data exchange activities between ships on IoS, in order to curb the spread of false data, it is necessary to support the traceability and auditability of data or instructions. Furthermore, considering the social connections between nodes and the lack of trust and other realistic conditions, various factors make blockchain a powerful tool to solve the standardization and security of data exchange in IoS and its cyberspace. Ships in IoS can use blockchain to record the summary of the navigation log on the chain, so as to achieve the tamper-proof of the ship's navigation log. Other measures in IoS to enhance cyberspace security, such as ship reputation calculation, event authenticity evaluation, etc., can also be implemented on the blockchain. Summary of the invention

[0004] The technical problem to be solved by the present invention is: a blockchain-based ship logbook notarization system to ensure the authenticity and reliability of IoS information exchange and to achieve the tamper-proof and traceability of ship logbooks.

[0005] A blockchain-based ship logbook notarization system, the system is built on a blockchain operating environment with a ship network, a block propagation protocol and a relationship network as the network architecture; wherein the ship network is used to support the transmission of application layer data between ships in a point-to-point or broadcast notification manner, wherein the point is a ship in the ship network; the digital identity of the ship and the crew is authenticated by the ship digital certificate and the crew digital certificate, which are issued by the Maritime Trust Center (MTA Maritime Trust) that is oriented to maritime shipping business and has global credibility The ship and the crew sign the information with the private key corresponding to the certificate, and the node in the ship network verifies the authenticity and integrity of the information with the public key corresponding to the certificate; in the ship network, the communication link between any two ships is selected according to the actual network conditions, and the candidate communication links include VDES, Inmarsat, 4G / 5G and Startlink, etc.; the block propagation protocol is established on the ship network using blockchain, and the blockchain program refers to the terminal program running on each node in the ship network. The program follows and executes the blockchain protocol, and a P2P network is formed through the ship network, in which the block propagation protocol is used to forward and propagate the ship's navigation log in the form of blocks between ships; the relationship network is a P2P network formed by ships through data interconnection, in which each ship node has a certain number of neighbor ships in the network space;

[0006] Ships in the ship network use blockchain to record navigation event logs and their summaries on the chain; after writing the navigation log, the ship encodes the information of the navigation log into a message according to a preset format, and fragments the log message according to a fixed time interval; and converts the log message into digital text, and adds the ship's time and space information to the digital text, and then performs digital summary processing on the digital text with time and space information, and signs it with the private key corresponding to the digital certificate, and broadcasts the signed message and its summary information to the P2P network in the form of a transaction; after verifying the message and its summary information on the P2P network, the witness ship packages the message and its summary information into a block and broadcasts it to the blockchain network; each ship blockchain system terminal synchronously receives the consensus block and adds it to the local terminal, so that each ship in the blockchain network has each ship's fragmented log and its digital summary information; the ship verifies the obtained block through the ship's digital certificate and checks the navigation log message in the block.

[0007] As a further technical solution of the present invention, the ship's navigation log is the main information of the ship during navigation and at anchor, which is preset according to navigation requirements:

[0008] The ship's navigation log is used to describe the relevant information of the navigation events that occurred in natural language; the ship's navigation log mainly includes two aspects, the ship's log entries and log fragments; log entries refer to the formatted log units manually recorded by the crew; log fragments refer to the collection of several log entries that are regularly and automatically assembled by the evidence storage program. The log evidence storage program broadcasts the assembled log fragments in the form of transactions (transactions) to the ship's P2P network, and after multi-party verification by the blockchain program, they are loaded into the blockchain; the broadcast notification refers to the use of the propagation protocol in the blockchain block to fully propagate the information on the ship network; there is no special log fragment in the local database, and the log fragment is assembled by the blockchain program from the local log entries Once a transaction is formed, it will be broadcasted to the blockchain network immediately; the transaction (transaction) fragment broadcasted to the blockchain network refers to the set of entries broadcasted to the P2P network, which is arranged from old to new in principle, with continuous entry serial numbers and signed with the private key corresponding to the ship's digital certificate to ensure its security; the blockchain elects ship witnesses through a consensus mechanism, and the witnesses package the unchained log fragments into blocks, which are then verified by the blockchain's consensus mechanism. The verified blocks are finally received by each node terminal and loaded into the local blockchain end; the log storage program regularly checks whether the existing log entries exist on the blockchain at a period T, and assembles the log entries that have not yet been loaded on the blockchain into log fragments, following the following rules:

[0009] (1) The timestamp of the log segment is no more than RECENT from the current time, where RECENT is a preset constant;

[0010] (2) Assemble a log entry into a log fragment and attempt to load it into the blockchain no more than REPEAT times, where REPEAT is a preset constant;

[0011] (3) If no new log entry is found to be loaded into the blockchain during this period, the log segment assembly and broadcast notification segment operations will not be performed; in particular, if there is no log entry recorded by the ship during a period, no transaction broadcast notification will be sent;

[0012] The ship's logbook consists of four parts: the first part is the ship information, which includes the ship's ID ShipIMO , Crew ID Crew , serial number of the ship's logbook fragment Seq , the sequence number of the log entry Log Seq , used to obtain relevant information about the ship that wrote the logbook; the second part is the logbook, including the continuous field Log of the logbook content data, longitude and latitude Location and event timestamp TimeStamp, which are used to understand the time, place and event details of the event; the third part is the details of the logbook message, including the digital information body LogBody of the logbook entry and the digital information body FragBody of the logbook fragment; the fourth part is the message anti-tampering and anti-repudiation information, that is, the private key Sign corresponding to the certificate used by the ship and crew ShipPriKey 、Sign CrewPriKey Sign the message digest.

[0013] As a further technical solution of the present invention, the ship's logbook is divided into three granularities;

[0014] A log entry is the smallest granularity of a ship's navigation log. Several log entries constitute a log fragment. A ship's log entry consists of the ship's identity, log entry serial number, longitude and latitude, event timestamp, continuous fields of the navigation log content, the identity of the crew member recorded in the log, and the private key signature corresponding to the crew member's digital certificate.

[0015] A log fragment consists of several log entries, and the log fragment will be broadcasted by the ship to the blockchain system at regular intervals. The log fragment is the smallest unit of the blockchain, and there are log fragments of multiple ships in one blockchain. The log fragment of a ship consists of the ship's identity, the serial number of the log fragment, the serial number interval of the log entry, the longitude and latitude, the timestamp, the log entry summary, the identity of the crew member recorded in the broadcast announcement log, and the private key signature corresponding to the ship's digital certificate.

[0016] Several log fragments eventually form a complete ship navigation log in the blockchain; the ships and crew members in the blockchain can consult the log by finding the public key corresponding to the ship certificate through the blockchain system, thus achieving the immutability and traceability of the ship navigation log.

[0017] As a further technical solution of the present invention, the digital information summary format of each granularity in the navigation log is represented as follows:

[0018] Logbook entry digital information summary format presentation format:

[0019] LogItem=LogBody | LogThumb | Sign CrewPriKey [LogThumb];

[0020] LogBody=Log data | ID ShipIMO | Log Seq | Location | TimeStamp | ID Crew ;

[0021] LogThumb = Hash[LogBody];

[0022] Each field has a fixed length and is filled in the form of a string, as described below:

[0023] Log entry structure LogItem: the digital information structure of the log entry, including the log entry body, log entry information summary and the private key signature corresponding to the crew certificate;

[0024] Log entry body LogBody: The main structure of the logbook, including the log content field, ship identity, log entry sequence number, latitude and longitude, timestamp and recorded crew;

[0025] LogThumb: The result of hashing the log entry using a cryptographic function that meets confidentiality requirements.

[0026] Report the private key signature corresponding to the crew certificate Sign CrewPriKey []: Sign the message information summary with the private key corresponding to the crew certificate to prevent the message from being tampered with and provide non-repudiation function;

[0027] Vessel ID ShipIMO : Use the IMO number of the reporting ship;

[0028] Logbook Record Crew ID Crew : The crew member who records the ship's logbook is represented by capital letters;

[0029] The serial number of the ship's logbook entry Log Seq : The message sequence number generated autonomously for broadcasting the ship's logbook entry to the P2P network, expressed in Arabic numerals;

[0030] Log content field Log data : Use natural language description, with bytes as the unit and the field length controlled within the specified length. Unused space needs to be filled with placeholders;

[0031] The latitude and longitude of the location where the incident occurred: represented by capital letters, Arabic numerals and symbols;

[0032] Event timestamp: The time when the logbook entry event occurred, represented by capital letters, Arabic numerals and symbols;

[0033] Logbook fragment digital information summary format representation:

[0034] LogFragment=FragmentBody | FragmentThumb | Sign ShipPriKey [FragmentThumb];

[0035] FragmentBody=ID Ship | LogItem | LogItem... | LogItem;

[0036] FragmentThumb=Hash[LogBody];

[0037] Log entry structure LogFragment: the digital information structure of the log fragment, including the log fragment body, log fragment information summary, and the private key signature corresponding to the ship certificate;

[0038] Log entry body FragmentBody: the log fragment structure, including several log entries and ship number;

[0039] Log entry structure LogItem: the digital information structure of the log entry, including the log entry body, log entry information summary and the private key signature corresponding to the crew certificate;

[0040] Digital information summary of the log fragment FragmentThumb: the result of hashing the log fragment using an encryption function that meets the confidentiality requirements;

[0041] Report the private key signature corresponding to the ship certificate Sign ShipPriKey []: The message information summary is signed with the private key corresponding to the ship certificate to prevent the message from being tampered with and provide anti-repudiation function.

[0042] As a further technical solution of the present invention, the system uses ships in the ship network as nodes and uses the blockchain generation principle based on the DPoS consensus mechanism; the DPoS consensus mechanism is an algorithm mechanism for ship nodes in the blockchain system to reach a consensus on new blocks:

[0043] The DPoS consensus mechanism uses ships in the ship networking network as nodes. In the DPoS consensus mechanism of the ship networking blockchain, block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes. Longer consensus time reduces the probability of forks, and more outbound nodes enable faster propagation of blocks in the ship networking network.

[0044] The blockchain generation principle based on the DPoS consensus mechanism consists of the election of witnesses and the witness block generation process:

[0045] The witness election process is as follows: In the DPoS consensus mechanism, witness elections are held every T1 time. The elected witnesses assemble the collected logbook information messages into blocks and broadcast them to the blockchain and other ships at a fixed time interval T2, where T1 represents the witness election interval and T2 represents the block generation interval;

[0046] The initial witnesses are randomly selected by the system. The blockchain system randomly selects N ships from M ship nodes to become witness nodes. These N ships will no longer participate in the next round of witness elections.

[0047] The ship broadcast notification log information message is regarded as a transaction. The witness will verify the digital summary of the ship broadcast notification log, package the valid log digital summary into a block broadcast notification to the blockchain network, and broadcast the notification to all ships for synchronization;

[0048] After T2 time, the next witness will verify, package, and broadcast the block until the last witness completes.

[0049] Then the next round of witness election begins, and the blockchain system will randomly select N ships from the remaining MN ship nodes to become witness nodes.

[0050] As a further technical solution of the present invention, the special DPoS consensus mechanism of the ship networking blockchain has the following characteristics due to the network heterogeneity of the ship networking:

[0051] The heterogeneous technical composition, complex topological structure and uneven distribution of ship nodes in the geographical space of the ship network lead to large differences in network communication delays between ships and ships and between ships and shores in different geographical locations, making the asynchrony of information transmission in IoS far more serious than that of the Internet. The ship network between different sea areas is asynchronous, with large network delays, and the cross-sea transmission delay of information in the ship network is relatively long.

[0052] The application of blockchain in ship networking needs to overcome the unbalanced network conditions during data transmission across distances. The DPoS consensus mechanism in ship networking is also different from the traditional blockchain DPoS consensus mechanism based on the Internet. The DPoS consensus mechanism in ship networking has the following particularities:

[0053] Ship Network DPoS consensus time T Ship Much longer than the DPoS consensus time T based on the traditional Internet blockchain Normal ; Setting up more outbound nodes allows blocks to propagate faster in the ship networking network; block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes.

[0054] As a further technical solution of the present invention, the ship log fragments of the ship networking blockchain have a special chain-up process;

[0055] After the blockchain system elects the ship witness node, the witness node authenticates and packages the fragments in the log fragment transaction pool;

[0056] After receiving the log fragment, the witness node verifies the integrity and authenticity of the message according to the digital certificate of the sender's ship. Each ship has the certificate public key of all ships in its relationship network. The witness checks the authenticity of the message through the public key corresponding to the certificate, and performs a series of transaction verification on the message through the routine inspection procedure of blockchain transactions. If the verification is successful, the fragment is placed in the packaged block; if the verification fails, the log fragment is discarded.

[0057] After assembling a new block, the witness node broadcasts the notification to the blockchain system, connects to the blockchain, and propagates the new block. When the new block is propagated to the next witness node, the next witness node repeats the above work;

[0058] In the relationship network, each ship establishes a trust relationship with some ships in the system based on its own background and navigation history, thereby forming its own relationship network; in the relationship network, the more complete the ship's navigation log is, the greater the credibility it has, and the easier it is to be elected as a witness node in the blockchain network; after the block recording the ship's navigation log is broadcast in the blockchain network, the maritime center will synchronize the new block to the local database to achieve the unchangeable and traceable nature of the ship's navigation log.

[0059] As a further technical solution of the present invention, the digital certificate is divided into a ship digital certificate and a crew digital certificate, which is the unique identifier of the ship and the crew:

[0060] The digital certificates of ships and crew members are digital identities issued uniformly by the credible Maritime Trust Center (MTA) for maritime shipping business. The digital certificates of ships and crew members are the only identity identifiers in the ship network blockchain; the crew members use the corresponding private key to sign the log entries for subsequent verification by readers; the ship uses the corresponding private key to sign the log fragments for subsequent verification by readers; after receiving the information message, the ship verifies the integrity and authenticity of the message according to the sender's ship digital certificate. If the verification is successful, it will be sent to the neighboring ships in the relationship network; if the verification fails, the information message will be discarded; the information can be tamper-proof by signing the information message with the private key corresponding to the ship digital certificate and the crew digital certificate.

[0061] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides a blockchain-based ship logbook storage system to ensure the authenticity and reliability of IoS information exchange and achieve the tamper-proof and traceability of ship logbooks. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is a log evidence program diagram in the system in an embodiment of the present invention.

[0063] Figure 2 Schematic diagram of the granular structure of a ship navigation log in a system in an embodiment of the present invention.

[0064] Figure 3 The figure is a flow chart of the chaining process of the ship log fragments in the system in the embodiment of the present invention. DETAILED DESCRIPTION

[0065] The technical solution of the present invention is further described in detail below in conjunction with specific implementation methods.

[0066] With reference to the accompanying drawings- Figures 1 to 3 The present invention further describes the process of the present invention. It is particularly noted that unless otherwise specifically described, the operation flow, presentation form and numerical calculation of the nodes and implementation steps described in the embodiments of the present invention do not limit the scope of the present invention. The specific embodiments described in the present invention are only used to explain the present invention and are not used to limit the present invention.

[0067] A blockchain-based ship logbook notarization system, the system is built on a blockchain operating environment with a ship network, a block propagation protocol and a relationship network as the network architecture; wherein the ship network is used to support the transmission of application layer data between ships in a point-to-point or broadcast notification manner, wherein the point is a ship in the ship network; the digital identity of the ship and the crew is authenticated by the ship digital certificate and the crew digital certificate, which are issued by the Maritime Trust Center (MTA Maritime Trust) that is oriented to maritime shipping business and has global credibility The ship and the crew sign the information with the private key corresponding to the certificate, and the node in the ship network verifies the authenticity and integrity of the information with the public key corresponding to the certificate; in the ship network, the communication link between any two ships is selected according to the actual network conditions, and the candidate communication links include VDES, Inmarsat, 4G / 5G and Startlink, etc.; the block propagation protocol is established on the ship network using blockchain, and the blockchain program refers to the terminal program running on each node in the ship network. The program follows and executes the blockchain protocol, and a P2P network is formed through the ship network, in which the block propagation protocol is used to forward and propagate the ship's navigation log in the form of blocks between ships; the relationship network is a P2P network formed by ships through data interconnection, in which each ship node has a certain number of neighbor ships in the network space;

[0068] Ships in the ship network use blockchain to record navigation event logs and their summaries on the chain; after writing the navigation log, the ship encodes the information of the navigation log into a message according to a preset format, and fragments the log message according to a fixed time interval; and converts the log message into digital text, and adds the ship's time and space information to the digital text, and then performs digital summary processing on the digital text with time and space information, and signs it with the private key corresponding to the digital certificate, and broadcasts the signed message and its summary information to the P2P network in the form of a transaction; after verifying the message and its summary information on the P2P network, the witness ship packages the message and its summary information into a block and broadcasts it to the blockchain network; each ship blockchain system terminal synchronously receives the consensus block and adds it to the local terminal, so that each ship in the blockchain network has each ship's fragmented log and its digital summary information; the ship verifies the obtained block through the ship's digital certificate and checks the navigation log message in the block.

[0069] like Figure 1 As shown, in this embodiment, the ship's navigation log is the main information of the ship during navigation and at anchor, which is preset according to the navigation requirements:

[0070] The ship's navigation log is used to describe the relevant information of the navigation events that occurred in natural language; the ship's navigation log mainly includes two aspects, the ship's log entries and log fragments; log entries refer to the formatted log units manually recorded by the crew; log fragments refer to the collection of several log entries that are regularly and automatically assembled by the evidence storage program. The log evidence storage program broadcasts the assembled log fragments in the form of transactions (transactions) to the ship's P2P network, and after multi-party verification by the blockchain program, they are loaded into the blockchain; the broadcast notification refers to the use of the propagation protocol in the blockchain block to fully propagate the information on the ship network; there is no special log fragment in the local database, and the log fragment is assembled by the blockchain program from the local log entries Once a transaction is formed, it will be broadcasted to the blockchain network immediately; the transaction (transaction) fragment broadcasted to the blockchain network refers to the set of entries broadcasted to the P2P network, which is arranged from old to new in principle, with continuous entry serial numbers and signed with the private key corresponding to the ship's digital certificate to ensure its security; the blockchain elects ship witnesses through a consensus mechanism, and the witnesses package the unchained log fragments into blocks, which are then verified by the blockchain's consensus mechanism. The verified blocks are finally received by each node terminal and loaded into the local blockchain end; the log storage program regularly checks whether the existing log entries exist on the blockchain at a period T, and assembles the log entries that have not yet been loaded on the blockchain into log fragments, following the following rules:

[0071] (1) The timestamp of the log segment is no more than RECENT from the current time, where RECENT is a preset constant;

[0072] (2) Assemble a log entry into a log fragment and attempt to load it into the blockchain no more than REPEAT times, where REPEAT is a preset constant;

[0073] (3) If no new log entry is found to be loaded into the blockchain during this period, the log segment assembly and broadcast notification segment operations will not be performed; in particular, if there is no log entry recorded by the ship during a period, no transaction broadcast notification will be sent;

[0074] The ship's logbook consists of four parts: the first part is the ship information, which includes the ship's ID ShipIMO , Crew ID Crew , serial number of the ship's logbook fragment Seq , the sequence number of the log entry Log Seq , used to obtain relevant information about the ship that wrote the logbook; the second part is the logbook, including the continuous field Log of the logbook content data, longitude and latitude Location and event timestamp TimeStamp, which are used to understand the time, place and event details of the event; the third part is the details of the logbook message, including the digital information body LogBody of the logbook entry and the digital information body FragBody of the logbook fragment; the fourth part is the message anti-tampering and anti-repudiation information, that is, the private key Sign corresponding to the certificate used by the ship and crew ShipPriKey 、Sign CrewPriKey Sign the message digest.

[0075] like Figure 2 As shown, in this embodiment, the ship's navigation log is divided into three granularities;

[0076] A log entry is the smallest granularity of a ship's navigation log. Several log entries constitute a log fragment. A ship's log entry consists of the ship's identity, log entry serial number, longitude and latitude, event timestamp, continuous fields of the navigation log content, the identity of the crew member recorded in the log, and the private key signature corresponding to the crew member's digital certificate.

[0077] A log fragment consists of several log entries, and the log fragment will be broadcasted by the ship to the blockchain system at regular intervals. The log fragment is the smallest unit of the blockchain, and there are log fragments of multiple ships in one blockchain. The log fragment of a ship consists of the ship's identity, the serial number of the log fragment, the serial number interval of the log entry, the longitude and latitude, the timestamp, the log entry summary, the identity of the crew member recorded in the broadcast announcement log, and the private key signature corresponding to the ship's digital certificate.

[0078] Several log fragments will eventually form a complete ship navigation log in the blockchain. Several log fragments will be packaged into a block in the blockchain, that is, a block can accommodate log fragments broadcast from multiple ships; ships and crew members in the blockchain can use the blockchain system to find the public key corresponding to the corresponding ship certificate to consult the log, thus realizing the immutability and traceability of the ship navigation log.

[0079] In this embodiment, the summary format of digital information of each granularity in the navigation log is as follows:

[0080] Logbook entry digital information summary format presentation format:

[0081] LogItem=LogBody | LogThumb | Sign CrewPriKey [LogThumb];

[0082] LogBody=Log data | ID ShipIMO | Log Seq| Location | TimeStamp | ID Crew ;

[0083] LogThumb = Hash[LogBody];

[0084] Each field has a fixed length and is filled in the form of a string, as described below:

[0085] Log entry structure LogItem: the digital information structure of the log entry, including the log entry body, log entry information summary and the private key signature corresponding to the crew certificate;

[0086] Log entry body LogBody: The main structure of the logbook, including the log content field, ship identity, log entry sequence number, latitude and longitude, timestamp and recorded crew;

[0087] LogThumb: The result of hashing the log entry using a cryptographic function that meets confidentiality requirements.

[0088] Report the private key signature corresponding to the crew certificate Sign CrewPriKey []: Sign the message information summary with the private key corresponding to the crew certificate to prevent the message from being tampered with and provide non-repudiation function;

[0089] Vessel ID ShipIMO : Use the IMO number of the reporting ship;

[0090] Logbook Record Crew ID Crew : The crew member who records the ship's logbook is represented by capital letters;

[0091] The serial number of the ship's logbook entry Log Seq : The message sequence number generated autonomously for broadcasting the ship's logbook entry to the P2P network, expressed in Arabic numerals;

[0092] Log content field Log data : Use natural language description, with bytes as the unit and the field length controlled within the specified length. Unused space needs to be filled with placeholders;

[0093] The latitude and longitude of the location where the incident occurred: represented by capital letters, Arabic numerals and symbols;

[0094] Event timestamp: The time when the logbook entry event occurred, represented by capital letters, Arabic numerals and symbols;

[0095] Logbook fragment digital information summary format representation:

[0096] LogFragment=FragmentBody | FragmentThumb | Sign ShipPriKey [FragmentThumb];

[0097] FragmentBody=ID Ship | LogItem | LogItem... | LogItem;

[0098] FragmentThumb=Hash[LogBody];

[0099] Log entry structure LogFragment: the digital information structure of the log fragment, including the log fragment body, log fragment information summary, and the private key signature corresponding to the ship certificate;

[0100] Log entry body FragmentBody: the log fragment structure, including several log entries and ship number;

[0101] Log entry structure LogItem: the digital information structure of the log entry, including the log entry body, log entry information summary and the private key signature corresponding to the crew certificate;

[0102] Digital information summary of the log fragment FragmentThumb: the result of hashing the log fragment using an encryption function that meets the confidentiality requirements;

[0103] Report the private key signature corresponding to the ship certificate Sign ShipPriKey []: The message information summary is signed with the private key corresponding to the ship certificate to prevent the message from being tampered with and provide anti-repudiation function.

[0104] In this embodiment, the system uses ships in the ship network as nodes and uses the blockchain generation principle based on the DPoS consensus mechanism; the DPoS consensus mechanism is an algorithm mechanism for ship nodes in the blockchain system to reach a consensus on new blocks:

[0105] The DPoS consensus mechanism uses ships in the ship networking network as nodes. In the DPoS consensus mechanism of the ship networking blockchain, block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes. Longer consensus time reduces the probability of forks, and more outbound nodes enable faster propagation of blocks in the ship networking network.

[0106] The blockchain generation principle based on the DPoS consensus mechanism consists of the election of witnesses and the witness block generation process:

[0107] The witness election process is as follows: In the DPoS consensus mechanism, witness elections are held every T1 time. The elected witnesses assemble the collected logbook information messages into blocks and broadcast them to the blockchain and other ships at a fixed time interval T2, where T1 represents the witness election interval and T2 represents the block generation interval;

[0108] The initial witnesses are randomly selected by the system. The blockchain system randomly selects N ships from M ship nodes to become witness nodes. These N ships will no longer participate in the next round of witness elections.

[0109] The ship broadcast notification log information message is regarded as a transaction. The witness will verify the digital summary of the ship broadcast notification log, package the valid log digital summary into a block broadcast notification to the blockchain network, and broadcast the notification to all ships for synchronization;

[0110] After T2 time, the next witness will verify, package, and broadcast the block until the last witness completes.

[0111] Then the next round of witness election begins, and the blockchain system will randomly select N ships from the remaining MN ship nodes to become witness nodes.

[0112] In this embodiment, the special DPoS consensus mechanism of the ship networking blockchain has the following characteristics due to the network heterogeneity of the ship networking:

[0113] The heterogeneous technical composition, complex topological structure and uneven distribution of ship nodes in the geographical space of the ship network lead to large differences in network communication delays between ships and ships and between ships and shores in different geographical locations, making the asynchrony of information transmission in IoS far more serious than that of the Internet. The ship network between different sea areas is asynchronous, with large network delays, and the cross-sea transmission delay of information in the ship network is relatively long.

[0114] The application of blockchain in ship networking needs to overcome the unbalanced network conditions during data transmission across distances. The DPoS consensus mechanism in ship networking is also different from the traditional blockchain DPoS consensus mechanism based on the Internet. The DPoS consensus mechanism in ship networking has the following particularities:

[0115] Ship Network DPoS consensus time T Ship Much longer than the DPoS consensus time T based on the traditional Internet blockchain Normal ; Setting up more outbound nodes allows blocks to propagate faster in the ship networking network; block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes.

[0116] like Figure 3 As shown, in this embodiment, the ship log fragment of the ship networking blockchain has a special chain-up process;

[0117] After the blockchain system elects the ship witness node, the witness node authenticates and packages the fragments in the log fragment transaction pool;

[0118] After receiving the log fragment, the witness node verifies the integrity and authenticity of the message according to the sender's ship digital certificate. Each ship has the public key of all ship certificates in its relationship network. The witness checks the authenticity of the message through the public key corresponding to the certificate, and performs a series of transaction verification on the message through the routine inspection procedure of blockchain transactions. If the verification is successful, the fragment is placed in the packaged block; if the verification fails, the log fragment is discarded.

[0119] After assembling a new block, the witness node broadcasts the notification to the blockchain system, connects to the blockchain, and propagates the new block. When the new block is propagated to the next witness node, the next witness node repeats the above work;

[0120] In the relationship network, each ship establishes a trust relationship with some ships in the system based on its own background and navigation history, thereby forming its own relationship network; in the relationship network, the more complete the ship's navigation log is, the greater the credibility it has, and the easier it is to be elected as a witness node in the blockchain network; after the block recording the ship's navigation log is broadcast in the blockchain network, the maritime center will synchronize the new block to the local database to achieve the unchangeable and traceable nature of the ship's navigation log.

[0121] In this embodiment, the digital certificates are divided into ship digital certificates and crew digital certificates, which are unique identifiers of the ship and crew:

[0122] The digital certificates of ships and crew members are digital identities issued uniformly by the credible Maritime Trust Center (MTA) for maritime shipping business. The digital certificates of ships and crew members are the only identity identifiers in the ship network blockchain; the crew members use the corresponding private key to sign the log entries for subsequent verification by readers; the ship uses the corresponding private key to sign the log fragments for subsequent verification by readers; after receiving the information message, the ship verifies the integrity and authenticity of the message according to the sender's ship digital certificate. If the verification is successful, it will be sent to the neighboring ships in the relationship network; if the verification fails, the information message will be discarded; the information can be tamper-proof by signing the information message with the private key corresponding to the ship digital certificate and the crew digital certificate.

[0123] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0124] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A blockchain-based ship logbook storage system, characterized in that: The system is built on a blockchain operating environment with ship networking, block propagation protocol and relationship network as network architecture; wherein, the ship networking is used to support the transmission of application layer data between ships in a point-to-point or broadcast notification manner, and the point is the ship in the ship networking; the digital identity of the ship and the crew is authenticated by the ship digital certificate and the crew digital certificate; the ship and the crew sign the information with the private key corresponding to the certificate, and the node in the ship networking verifies the authenticity and integrity of the information with the public key corresponding to the certificate; the block propagation protocol is established on the ship networking that applies the blockchain, and the blockchain program refers to the terminal program running on each node in the ship networking, and the program follows and executes the blockchain protocol, and a P2P network is formed through the ship networking, wherein the block propagation protocol is used to forward and propagate the ship navigation log in the form of blocks between ships; the relationship network is a P2P network formed by ships through data interconnection, wherein each ship node has a certain number of neighbor ships in the network space; Ships in the ship network use blockchain to record navigation event logs and summaries on the chain; after writing the navigation log, the ship encodes the information of the navigation log into a message according to a preset format, and divides the log message into pieces according to fixed time intervals; and converts the log message into digital text, and adds the ship's time and space information to the digital text, and then performs digital summary processing on the digital text with time and space information, and signs it with the private key corresponding to the digital certificate, and broadcasts the signed message and its summary information to the P2P network in the form of a transaction; after verifying the message and its summary information on the P2P network, the witness ship packages the message and its summary information into a block and broadcasts it to the blockchain network; each ship blockchain system terminal synchronously receives the consensus block and adds it to the local terminal, so that each ship in the blockchain network has each ship's shard log and its digital summary information; the ship verifies the obtained block through the ship's digital certificate and checks the navigation log message in the block; The ship's navigation log is information about the situation of the ship during navigation and at anchor, which is preset according to navigation requirements; The ship's navigation log is used to describe the relevant information of the navigation events that occurred in natural language; the ship's navigation log includes two aspects, the ship's log entries and log fragments; log entries refer to the formatted log units manually recorded by the crew; log fragments refer to the collection of several log entries that are regularly and automatically assembled by the evidence storage program. The log evidence storage program broadcasts the assembled log fragments to the ship's P2P network in the form of transactions, and after multi-party verification by the blockchain program, they are loaded into the blockchain; the broadcast notification refers to the use of the propagation protocol in the blockchain block to fully propagate the information on the ship network; there is no special log fragment in the local database, and the log fragment is assembled by the blockchain program from the local log entries. Once a transaction is completed, it will be broadcasted to the blockchain network immediately; the transaction fragments broadcasted to the blockchain network refer to the set of entries broadcasted to the P2P network, which are arranged from old to new in principle, with continuous entry serial numbers and signed with the private key corresponding to the ship's digital certificate to ensure its security; the blockchain elects ship witnesses through a consensus mechanism, and the witnesses package the unchained log fragments into blocks, which are then verified by the blockchain's consensus mechanism. The verified blocks are finally received by each node terminal and loaded into the local blockchain end; the log storage program regularly checks whether the existing log entries exist on the blockchain at a period T, and assembles the log entries that have not yet been loaded on the blockchain into log fragments, following the following rules: (1) The timestamp of the log segment is no more than RECENT from the current time, where RECENT is a preset constant; (2) Assemble a log entry into a log fragment and attempt to load it into the blockchain no more than REPEAT times, where REPEAT is a preset constant; (3) If no new log entry is found that can be loaded into the blockchain within this cycle, the log fragment assembly and broadcast fragment operations will not be performed; if there is no log entry record for a ship within a cycle, no transaction broadcast notification will be sent; The ship's logbook consists of four parts: the first part is the ship information, which includes the ship's ID ShipIMO , Crew ID Crew , serial number of the ship's logbook fragment Seq , the sequence number of the log entry Log Seq , used to obtain relevant information about the ship that wrote the logbook; the second part is the logbook, including the continuous field Log of the logbook content data , longitude and latitude Location and event timestamp TimeStamp, which are used to understand the time, location and details of the event; the third part is the details of the logbook message, including the digital information body LogBody of the logbook entry and the digital information body FragBody of the logbook fragment; the fourth part is the message tamper-proof and anti-repudiation information, that is, the private key Sign corresponding to the digital certificate used by the ship and the crew ShipPriKey 、Sign CrewPriKey Sign the message information digest; The ship logbook is divided into three granularities; A log entry is the smallest granularity of a ship's navigation log. Several log entries constitute a log fragment. A ship's log entry consists of the ship's identity, log entry serial number, longitude and latitude, event timestamp, continuous fields of the navigation log content, the identity of the crew member recorded in the log, and the private key signature corresponding to the crew member's digital certificate. A log fragment consists of several log entries, which will be broadcasted by the ship to the blockchain system at regular intervals. A log fragment is the smallest unit of the blockchain, and a blockchain includes log fragments of multiple ships. A ship's log fragment consists of the ship's identity, the serial number of the log fragment, the serial number interval of the log entry, the longitude and latitude, the timestamp, the log entry summary, the identity of the crew member recorded in the broadcast announcement log, and the private key signature corresponding to the ship's digital certificate. Several log fragments will be packaged into a block in the blockchain, that is, one block can contain log fragments broadcast from multiple ships; the ships and crew in the blockchain can review and verify the logs through the blockchain system.

2. According to the blockchain-based ship logbook storage system of claim 1, it is characterized in that: The representation of each granularity in the navigation log is as follows: Logbook entries are presented in the following format: LogItem=LogBody | LogThumb | Sign CrewPriKey [LogThumb]; LogBody=Log data | ID ShipIMO | Log Seq | Location | TimeStamp | ID Crew ; LogThumb = Hash[LogBody]; Each field has a fixed length and is filled in the form of a string, as described below: Log item structure LogItem: the digital information structure of the log item, including the log item body, the log item digital information summary and the private key signature corresponding to the crew certificate; Log entry body LogBody: The main structure of the logbook, including the log content field, ship identity, log entry sequence number, latitude and longitude, timestamp and recorded crew; LogThumb: The result of hashing the log entry using a cryptographic function that meets confidentiality requirements. Report the private key signature corresponding to the crew certificate Sign CrewPriKey []: Sign the message information summary with the private key corresponding to the crew certificate to prevent the message from being tampered with and provide non-repudiation function; Vessel ID ShipIMO : Use the IMO number of the reporting ship; Logbook Record Crew ID Crew : The crew member who records the ship's logbook is represented by capital letters; The serial number of the ship's logbook entry Log Seq : The message sequence number generated autonomously for broadcasting the ship's logbook entry to the P2P network, expressed in Arabic numerals; Log content field Log data : Use natural language description, with bytes as the unit and the field length controlled within the specified length. Unused space needs to be filled with placeholders; The latitude and longitude of the location where the incident occurred: represented by capital letters, Arabic numerals and symbols; Event timestamp: the time when the event in the logbook entry occurred, expressed in uppercase English letters, Arabic numerals and symbols; Logbook snippet representation: LogFragment=FragmentBody | FragmentThumb | Sign ShipPriKey [FragmentThumb]; FragmentBody=ID Ship | LogItem | LogItem... | LogItem ; FragmentThumb=Hash[LogBody]; LogFragment structure: the digital information structure of the log fragment, including the log fragment body, the log fragment digital information summary, and the private key signature corresponding to the ship certificate; Log fragment body FragmentBody: the navigation log fragment structure, including several log entries and ship number; Log item structure LogItem: the digital information structure of the log item, including the log item body, the log item digital information summary and the private key signature corresponding to the crew certificate; Digital information summary of the log fragment FragmentThumb: the result of hashing the log fragment using an encryption function that meets the confidentiality requirements; Report the private key signature corresponding to the ship certificate Sign ShipPriKey []: The message information summary is signed with the private key corresponding to the ship certificate to prevent the message from being tampered with and provide anti-repudiation function.

3. According to the blockchain-based ship logbook storage system of claim 1, it is characterized in that: The system uses ships in the ship network as nodes and uses the blockchain generation principle based on the DPoS consensus mechanism; the DPoS consensus mechanism is an algorithm mechanism for ship nodes in the blockchain system to reach a consensus on new blocks: The DPoS consensus mechanism uses ships in the ship networking as nodes. In the DPoS consensus mechanism of the ship networking blockchain, block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes. The blockchain generation principle based on the DPoS consensus mechanism consists of the election of witnesses and the witness block generation process: The witness election process is as follows: In the DPoS consensus mechanism, witness elections are held every T1 time. The elected witnesses assemble the collected logbook information messages into blocks and broadcast them to the blockchain and other ships at a fixed time interval T2, where T1 represents the witness election interval and T2 represents the block generation interval; The initial witnesses are randomly selected by the system. The blockchain system randomly selects N ships from M ship nodes to become witness nodes. These N ships will no longer participate in the next round of witness elections. The ship broadcast notification log information message is regarded as a transaction. The witness will verify the digital summary of the ship broadcast notification log, package the valid log digital summary into a block broadcast notification to the blockchain network, and broadcast the notification to all ships for synchronization; After T2 time, the next witness will verify, package and broadcast the block until the last witness completes the task; Then the next round of witness election begins, and the blockchain system will randomly select N ships from the remaining MN ship nodes to become witness nodes.

4. According to the blockchain-based ship logbook storage system of claim 3, it is characterized in that: The DPoS consensus mechanism of the ship networking blockchain has the following characteristics due to the network heterogeneity of the ship networking: The application of blockchain in ship networking needs to overcome the unbalanced network conditions during data transmission across distances. The DPoS consensus mechanism in ship networking is also different from the traditional blockchain DPoS consensus mechanism based on the Internet. The DPoS consensus mechanism in ship networking has the following particularities: Ship Network DPoS consensus time T Ship Much longer than the DPoS consensus time T based on the traditional Internet blockchain Normal ; Setting more message outbound nodes allows blocks to propagate faster in the ship networking network; block-holding nodes are more inclined to propagate blocks to nearby neighboring nodes.

5. According to the blockchain-based ship logbook storage system of claim 1, it is characterized in that: The ship log fragments of the ship network blockchain have a special chain-up process; After the blockchain system elects the ship witness node, the witness node authenticates and packages the fragments in the log fragment transaction pool; After receiving the log fragment, the witness node verifies the integrity and authenticity of the message according to the digital certificate of the sender's ship. Each ship has the certificate public key of all ships in its relationship network. The witness checks the authenticity of the message through the public key corresponding to the certificate, and performs a series of transaction verification on the message through the routine inspection procedure of blockchain transactions. If the verification is successful, the fragment is placed in the package block; if the verification fails, the log fragment is discarded. After assembling a new block, the witness node broadcasts the notification to the blockchain system, connects to the blockchain, and propagates the new block. When the new block is propagated to the next witness node, the next witness node repeats the above process; In the relationship network, each ship establishes a trust relationship with some ships in the system based on its own background and navigation history, thereby forming a relationship network; in the relationship network, the more complete the ship's navigation log is, the greater the credibility it has, and the easier it is to be elected as a witness node in the blockchain network; after the block recording the ship's navigation log is broadcast in the blockchain network, the maritime center will synchronize the new block to the local database.

6. According to the blockchain-based ship logbook storage system of claim 3, it is characterized in that: The digital certificates of ships and crew members are the unique identifiers of the ship and crew members: The digital certificate of the ship and the digital certificate of the crew are digital identities uniformly issued by a credible maritime trust center for maritime shipping business. The digital certificate of the ship and the digital certificate of the crew are the only identity identifiers in the ship network blockchain; the crew uses the private key corresponding to the digital certificate to sign the log entry for subsequent verification by the reader; the ship uses the private key corresponding to the digital certificate to sign the log fragment for subsequent verification by the reader; after receiving the information message, the ship verifies the integrity and authenticity of the message according to the sender's ship digital certificate. If the verification is successful, it will be sent to the neighboring ship in the relationship network; if the verification fails, the information message will be discarded; signing the information message with the private key corresponding to the ship digital certificate and the crew digital certificate can make the information tamper-proof.

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