Earth data resource-oriented cross-domain sharing system and method

Abstract

The invention discloses an earth data resource-oriented cross-domain sharing system and method, and an earth data resource directory service, which are used for carrying out structured analysis on different sources and different types of earth data resources, extracting earth data resource core meta-information, establishing a unified earth data resource model, instantiating the earth data resource model, and establishing an earth data resource database. Associating and integrating the earth resource data in each domain and the whole domain, constructing an earth data resource directory, and establishing a data unique identifier by using a data type, a spatial range, a spatial hierarchy and a time range; the cross-domain resource acquisition module performs dynamic positioning of the earth data resources on the premise of balancing resources and efficiency, realizes cross-domain efficient acquisition of the earth data resources based on a reverse proxy technology, restrains cross-domain acquisition behaviors of users from two aspects of authority hierarchical control and risk behavior limitation, intercepts acquisition of users exceeding authority definition, and performs resource allocation on the users. Obtaining limitation is carried out for obtaining behaviors with potential risks; the earth data resource hybrid backup mechanism comprehensively considers acquisition efficiency and security factors in an earth data resource backup process, and provides a hybrid earth data resource division strategy and a copy migration strategy. By establishing a cross-regional coordination mechanism, the resource utilization efficiency is improved, and deep sharing of earth data resources is promoted.

Description

Technical Field

[0001] The present invention relates to the field of geographic information technology, and in particular to a cross-domain sharing system and method for earth data resources. Background Art

[0002] In recent years, with the development of remote sensing technology, global positioning system (GPS), geographic information system (GIS) and mobile Internet, earth data resources are growing at an unprecedented rate. Considering the demand for storage resources, computing resources and network resources in the management and use of these massive earth data resources, many research organizations and institutions have established earth data resource centers of a certain scale nearby to realize the centralized management of earth data resources in the domain. However, with the continuous expansion of the number of earth data resources and the deepening of their applications, this relatively independent traditional organizational model has caused a certain degree of resource waste. On the one hand, earth data resource centers in different domains may repeatedly process and store the same data, resulting in unnecessary consumption of human resources, computing resources and storage space; the independence of earth data resource centers in different domains may lead to the lack of a unified mechanism and platform for data sharing, which restricts the cross-domain data circulation and utilization, resulting in data island phenomenon.

[0003] Therefore, there is an urgent need to provide a cross-domain data sharing solution to address the issue of sharing earth data resources across the entire region, improve resource utilization efficiency by establishing a cross-regional coordination mechanism, and promote in-depth sharing of earth data resources. Summary of the invention

[0004] The purpose of the present invention is to provide a cross-domain sharing system and method for earth data resources.

[0005] The technical solution to achieve the purpose of the present invention is: a cross-domain sharing system for earth data resources, including:

[0006] Earth data resource directory service is used to perform structured analysis on earth data resources of different sources and types, extract core metadata of earth data resources, and establish a unified earth data resource model using ontology technology; extract metadata and semantic conversion of earth data resources from different sources through text data processing and cleaning methods, and instantiate the earth data resource model; associate and integrate earth resource data in each domain and the entire domain, build an earth data resource directory, and establish a unique identifier for data using data type, spatial range, spatial level, and time range;

[0007] The cross-domain resource acquisition module is used to dynamically locate earth data resources while balancing resources and efficiency, and to achieve efficient cross-domain acquisition of earth data resources based on reverse proxy technology. It constrains users' cross-domain acquisition behaviors from two aspects: permission classification control and risk behavior restriction, intercepts user acquisition that exceeds the permission definition, and imposes acquisition restrictions on acquisition behaviors with potential risks, to ensure the security of cross-domain earth data resource acquisition.

[0008] The hybrid backup mechanism for earth data resources is used to comprehensively consider the acquisition efficiency and security factors in the process of backing up earth data resources, and provide a hybrid earth data resource division strategy and replica migration strategy. The hybrid earth data resource division strategy designs a multi-node resource criticality division plan. Core critical resources and restricted access resources use local backup storage, and basic public data resources and open shared data use multi-node off-site master-slave. The replica migration strategy design considers the differentiated replica migration process of data volume. Periodic incremental replicas are actively migrated across domains through the global directory service, and real-time differential replicas are passively migrated within the domain after the cross-domain acquisition of earth data resources is completed.

[0009] Furthermore, the earth data resource directory service includes two parts: earth data resource model and cross-domain resource publishing service, among which:

[0010] The Earth data resource model conducts structured analysis on Earth data resources of different sources and types, extracts the core metadata of Earth data resources, and uses ontology technology to establish a unified model structure; through text information processing and cleaning operations, it extracts metadata and performs semantic conversion on Earth data resources in different domains, and completes the instantiation of the Earth data resource model, which includes:

[0011] 1) Read the spatial coordinate system and time zone in the meta-information to complete the extraction of spatiotemporal reference information;

[0012] 2) Read the origin and affine coefficients in the meta-information, calculate the spatial range, and complete the spatial information extraction;

[0013] 3) Read the time version information in the meta information and complete the time information extraction;

[0014] 4) Read the sensor identification, product level, reference system, projection parameters, and band in the meta-information to extract other attribute information;

[0015] 5) Filling the earth data resource model with the information extracted in 1)-4) to complete the instantiation process of the earth data resource model;

[0016] Cross-domain resource publishing service, establish the mapping relationship between the earth data resource model structure and the earth data resource directory at the attribute level, conduct similarity analysis on earth data resources in different domains, associate and aggregate earth data resources with high similarity, and build a unified global earth data resource directory; use the data type, spatial range, spatial level, and time range of earth data resources to establish a unique identifier for earth data resources to ensure the uniqueness requirements of earth data resource discovery, including:

[0017] Determine the content of the earth data resource directory and complete the attribute mapping. The earth data resource directory provides the ability to search and describe earth data resources in the entire domain and in each domain, mainly including earth data resource identification, resource registration time, resource coverage, resource product level, and source unit information; map the earth data resource model structure with the earth data resource directory, for example, map the spatial information in the earth data resource model to the resource coverage of the earth data resource directory, map the time information to the resource registration time, and map the product number to the resource product level;

[0018] The spatial information and attribute information of earth data resources are used to establish data association and complete the aggregation of earth data resources, that is, to calculate the spatial association and attribute association between different earth data resources registered in the earth resource directory. The spatial association is to calculate the spatial association between the data from the spatial topological relationship and spatial distance measurement between the two data; the attribute association is to calculate the association of earth data resources from whether the attributes of different earth data resources match and whether the attribute values ​​are consistent; earth data resources with high spatial association and attribute association (such as spatial association value close to 1) are aggregated in the directory to provide unified resource acquisition capabilities;

[0019] Establish a unique identifier for earth data resources, that is, to sequentially concatenate the type code, Hilbert curve code, maximum spatial level, time code, and 4-bit random code of the earth data resource to form an identifier for the earth data resource for quick retrieval.

[0020] Furthermore, the cross-domain resource acquisition system includes two parts: a cross-domain earth data resource acquisition module and a resource acquisition hierarchical control module, wherein:

[0021] The cross-domain earth data resource acquisition module defines the cross-domain earth data resource acquisition process including the user authentication process. The forwarding of inter-domain resource acquisition requests is realized through the cross-domain resource gateway, which is realized by integrating external proxy services (such as nginx); the user authentication process is completed by integrating external user services (hereinafter referred to as unified user services). The process of users in the current domain (domain 2) cross-domain acquiring earth data resources in the target domain (domain 1) includes:

[0022] 1) The terminal user of the current domain (domain 2) initiates a service acquisition request to the earth data resource service of the target domain (domain 1) through the cross-domain resource gateway, and the request carries the user token information;

[0023] 2) The target domain (domain 1) earth data resource service requests the unified user service to verify the identity information;

[0024] 3) The user service of the target domain (domain 1) requests addressing from the earth data resource directory of the domain (domain 1) and obtains the addressing result;

[0025] 4) The unified user service of the target domain (domain 1) requests the unified user service of the entire domain to verify the identity information through the cross-domain resource gateway;

[0026] 5) The unified user service of the entire domain verifies the identity information and performs authentication control according to the identity authority, and then returns the result to the unified user service of the target domain (domain 1) through the cross-domain resource gateway;

[0027] 6) After the target domain (domain 1) unified user service obtains the return result, it returns the authentication result to the target domain (domain 1) earth data resource service;

[0028] 7) If the verification is successful and the requested service is within the user's authorization scope, the target domain (domain 1) earth data resource service will release the earth data resource service business request and return the earth data resource to the terminal in the current domain (domain 2) through the cross-domain resource gateway; if the verification is unsuccessful or the requested service is not within the user's authorization scope, the target domain (domain 1) earth data resource service will refuse to provide resource acquisition service, and the terminal in the current domain (domain 2) will not be able to obtain earth data resources;

[0029] The resource acquisition hierarchical control module defines the data acquisition strategy that matches the user roles and permissions, restricting the user's acquisition of earth data resources outside the scope of the permissions. Specifically, the resource acquisition evaluation results are calculated based on three indicators: user role level, operation risk level, and earth data resource criticality level. When the evaluation result is 1, access is allowed, and when it is 0, access is not allowed. Among them:

[0030] The User Role Level (UL) represents the level of the user's role, which is divided into three categories: Resource Administrator (RA), Resource Producer (RP), and Resource User (RU). There are three possible role level values: 0.1, 0.5, and 0.9. The Operation Risk Level (ORL) represents the risk impact of the resource acquisition operation that the user attempts to perform. The risk impact of the four types of operations, resource acquisition, resource update, resource editing, and resource deletion, has a possible value of 0.1, 0.5, 0.8, and 0.9, respectively. The Resource Criticality Level (RCL) of the Earth Data Resource is determined based on the spatial resolution, shooting time, and data quality of the Earth Data Resource. The higher the spatial resolution, the later the shooting time, and the higher the data quality, the higher the criticality level. It is obtained by weighting the expert scores, and there are three possible values: 0.25, 0.5, 0.75, and 1. The Resource Access Score (RAS) can be expressed as

[0031]

[0032] Furthermore, the cross-domain earth data resource acquisition module defines a set of adjustable resource positioning strategies, and dynamically updates effective acquisition resources according to environmental conditions through a combination of resource acquisition evaluation indicators, completing the dynamic positioning of earth data resources without user awareness, including:

[0033] Resource location strategies include Efficiency-first Access Strategy (EFS), Stability-first Access Strategy (SFAS), Multi-factor Balanced Strategy (MFBS), Access Locked Strategy to Special Resources (ALSSR), etc. The results are obtained by combining a set of custom resource acquisition evaluation indicators to sort the earth data resources. The higher the score, the more the earth data resource conforms to the resource location strategy. Resource acquisition indicators include Normalized Distance (ND), Normalized Response Time (NRT), Success Rate (SR), Resource Cross-domain Status (RCDS), and Resource Load Index (RLI). The value range of RCDS is 0 and 1, that is, RCDS of data within the domain is 0, and RCDS of cross-domain data is 1; the value range of RLI is 0 to 1, that is, the greater the load, the closer the RLI is to 1, otherwise the RLI is closer to 0.

[0034] EFS is an efficiency score after evaluating indicators such as resource distance, resource acquisition response time, resource cross-domain status, and resource current load index. Specifically, EFS can be expressed as

[0035]

[0036] Here, α is a constant ranging from 0 to 1.

[0037] SFAS is a stability score after evaluating indicators such as resource acquisition success rate, resource cross-domain status, and resource current load index. It can be specifically expressed as

[0038] SFAS=(α+RCDS)RCDS·SR·RLI

[0039] MFBS is a balance score after evaluating indicators such as resource distance, resource acquisition success rate, resource acquisition response time, resource cross-domain status, and resource current load index. It is a balance between network bandwidth occupancy, acquisition reliability, and acquisition efficiency. It can be specifically expressed as

[0040]

[0041] ALSSR means that some special earth data resources only provide services to specific users or clients, which is achieved by binding with user permissions. Other non-bound users cannot find and use the earth data resources during cross-domain resource positioning.

[0042] Furthermore, the resource acquisition classification control module also calculates the user acquisition risk index based on the user's acquisition behavior, and reduces the level of data that can be obtained for users with a higher risk index, wherein the user acquisition frequency, acquisition duration, and resource level are considered when calculating the user acquisition risk index;

[0043] User acquisition risk index UARL corresponding to the i-th user i It can be expressed as

[0044]

[0045] Where N is the total number of earth data resources, M is the total number of earth data resources accessed by the i-th user, They respectively represent the acquisition frequency, acquisition duration, and resource level of the mth earth data resource accessed by the ith user.

[0046] Furthermore, the hybrid backup mechanism of earth data resources includes a hybrid earth data resource partitioning strategy and a replica migration strategy, wherein:

[0047] A hybrid strategy for dividing earth data resources: core key resources and restricted access resources use local backup storage, and data backup nodes are set up in the domain. When acquiring core key resources, local master node data is obtained first. When the master node data is abnormally obtained, the data is switched to the local backup node data. Basic public data resources and open shared data use remote master and backup, and data backup nodes are set up in multiple different domains. When acquiring basic public data resources and open shared data, local master node data is obtained first. When the master node data is abnormally obtained, the data of backup nodes in other domains is obtained based on the cross-domain data service acquisition function.

[0048] The replica migration strategy first detects the dynamic changes of the global earth data resource directory at dynamic time intervals to extract incremental earth data resources, build incremental replicas, and then synchronize the incremental replicas to the backup nodes through the underlying data synchronization service to complete the periodic incremental replica migration process. For asynchronous data within the change detection interval, the differential data should be cached to the backup node after the cross-domain acquisition is completed, and the real-time differential replica migration process is completed through the real-time caching of differential data.

[0049] Furthermore, in the replica migration strategy, the detection time interval RMCDI is a dynamic result obtained by weighting the update intervals RCDI of different earth data resources by key levels within a certain period of time in the past. The calculation method is:

[0050]

[0051] Among them, RCL i and RCDI i are the critical level and update interval of the i-th updated earth data resource, and M is the total number of updated earth data resources.

[0052] A cross-domain sharing method for earth data resources, using the cross-domain sharing system for earth data resources to achieve cross-domain sharing of earth data resources, comprising:

[0053] Using the earth data resource directory service, we can conduct structured analysis on earth data resources of different sources and types, extract the core meta-information of earth data resources, and use ontology technology to establish a unified earth data resource model; through text data processing and cleaning methods, we can extract meta-information and semantic conversion of earth data resources from different sources, and instantiate the earth data resource model; we can associate and integrate earth resource data in each domain and the entire domain, build an earth data resource directory, and establish a unique data identifier using data type, spatial range, spatial level, and time range;

[0054] Using the cross-domain resource acquisition module, the earth data resources are dynamically located under the premise of balancing resources and efficiency, and the cross-domain efficient acquisition of earth data resources is realized based on the reverse proxy technology; the cross-domain acquisition behavior of users is restricted from two aspects: permission classification control and risk behavior restriction, and the user acquisition that exceeds the permission definition is intercepted. The acquisition restriction is implemented for the acquisition behavior with potential risks to ensure the security of cross-domain earth data resource acquisition;

[0055] By using the hybrid backup mechanism of earth data resources and comprehensively considering the acquisition efficiency and security factors in the process of earth data resource backup, a hybrid earth data resource division strategy and replica migration strategy are provided. The hybrid earth data resource division strategy designs a multi-node resource criticality division scheme. The core key resources and restricted acquisition resources are stored locally, and the basic public data resources and open shared data are stored in multiple nodes in different locations. The replica migration strategy design considers the differentiated replica migration process of data volume. The periodic incremental replica is actively migrated across domains through the global directory service, and the real-time differential replica is passively migrated within the domain after the cross-domain acquisition of earth data resources is completed.

[0056] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the cross-domain sharing system for earth data resources is implemented to realize cross-domain sharing of earth data resources.

[0057] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the cross-domain sharing system for earth data resources is implemented to realize cross-domain sharing of earth data resources.

[0058] Compared with the prior art, the present invention has the following significant advantages: 1) By constructing an earth data resource directory, effective integration and utilization of earth data resources can be achieved; 2) a dynamic resource positioning mechanism is provided to improve the efficiency of obtaining earth data resources, and controllable sharing is achieved by combining user permissions and behavioral risk analysis, thereby ensuring the security of cross-domain earth data resource acquisition; 3) based on the differences in the degree of openness and importance of data, a hybrid backup mechanism for earth data resources is adopted. When the information system of a certain domain suffers an accident and cannot provide data, data from other domains can still be obtained through a cross-domain proxy, thereby ensuring high reliability of data acquisition; 4) based on the above means, the present invention solves the problem of cross-domain sharing of large-scale earth data resources, opens up the link between earth data resource acquisition and rapid application between different domains, and effectively improves the utilization efficiency of earth data resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is the overall structural diagram of the cross-domain sharing system for earth data resources.

[0060] Figure 2 It is a structural diagram of the earth data resource model.

[0061] Figure 3 It is a flow chart of cross-domain earth data resource services.

[0062] Figure 4 It is a flow chart for cross-domain acquisition of earth data resources.

[0063] Figure 5 This is a flowchart of differential copy migration. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0065] The present invention aims at the problem of sharing earth data resources in the whole domain, integrates technologies such as earth data resource directory service, cross-domain earth data resource acquisition system, and earth data resource hybrid backup mechanism, and realizes earth data resource sharing by establishing a cross-regional coordination mechanism.

[0066] A cross-domain sharing system for earth data resources, with an overall structure such as Figure 1 As shown, it includes earth data resource directory service, cross-domain resource acquisition system, and earth data resource hybrid backup mechanism.

[0067] 1. Earth Data Resource Catalog Service

[0068] The Earth Data Resource Catalog Service conducts structured analysis on Earth Data Resources of different sources and types, extracts the core metadata of Earth Data Resources, and uses ontology technology to establish a unified Earth Data Resource model. Through text data processing and cleaning methods, it extracts metadata and semantic conversion of Earth Data Resources from different sources, and instantiates the Earth Data Resource model. It associates and integrates Earth Resource Data in each domain and the entire domain, builds an Earth Data Resource Catalog, and uses information such as data type, spatial range, spatial level, and time range to establish a unique data identifier.

[0069] The earth data resource directory service includes two parts: earth data resource model and cross-domain earth data resource service. The specific implementation steps are as follows:

[0070] (1) Earth Data Resource Model

[0071] The earth data resource model is an abstract model of earth data resources established using ontology technology. Through a structured method, it comprehensively represents earth data resources from the aspects of spatial dimension, temporal dimension, data quality dimension, attribute dimension, etc., which is conducive to establishing a unified earth data resource directory for the entire domain. Perform structured analysis on earth data resources of different sources and types, extract the core metadata of earth data resources, and use ontology technology to establish a unified earth data resource model. Through text information processing, cleaning and other operations, extract metadata of earth data resources in different domains, complete the filling of the earth data resource model, and build an earth data resource directory. Specifically include:

[0072] 1) Read the spatial coordinate system, time zone, etc. in the meta-information to complete the extraction of spatiotemporal reference information;

[0073] 2) Read the origin, affine coefficients, etc. in the meta-information, calculate the spatial range, and complete the spatial information extraction;

[0074] 3) Read the time version information in the meta information and complete the time information extraction;

[0075] 4) Read the sensor identification, product level, reference system, projection parameters, band and other information in the meta-information to complete the extraction of other attribute information;

[0076] 5) Use the information extracted in 1)-4) to fill in the attributes of the earth data resource model to complete the instantiation process of the earth data resource model.

[0077] (2) Cross-domain earth data resource services

[0078] Cross-domain earth data resource services establish a mapping relationship between the earth data resource model structure and the earth data resource directory at the attribute level, conduct similarity analysis on earth data resources in different domains, associate and aggregate earth data resources with high similarity, and build a unified global earth data resource directory; use the data type, spatial range, spatial level, time range, etc. of earth data resources to establish a unique identifier for earth data resources to ensure the uniqueness requirements of earth data resource discovery.

[0079] 2. Cross-domain resource acquisition system

[0080] The cross-domain resource acquisition system implements the cross-domain earth data resource acquisition process based on reverse proxy technology, dynamically locates earth data resources on the premise of balancing resources and efficiency, and realizes cross-domain efficient acquisition of earth data resources. It constrains users' cross-domain acquisition behavior from two aspects: permission classification control and risk behavior restriction, intercepts user acquisition beyond the permission definition, and implements acquisition restrictions for acquisition behaviors with potential risks to ensure the security of cross-domain earth data resource acquisition.

[0081] The cross-domain resource acquisition system includes two parts: cross-domain earth data resource acquisition and resource acquisition hierarchical control. The cross-domain resource acquisition behavior of users is constrained from two aspects: permission hierarchical control and risk behavior restriction. The specific implementation steps are as follows:

[0082] (1) Cross-domain earth data resource acquisition

[0083] Cross-domain earth data resource acquisition defines the cross-domain earth data resource acquisition process including the user authentication process. Taking the cross-domain acquisition of earth data resources of the target domain (domain 1) by the user of the current domain (domain 2) as an example, the specific cross-domain earth data resource acquisition process is explained. Among them, the user authentication process is mainly completed by integrating external user services (hereinafter referred to as unified user services).

[0084] 1) The terminal user of the current domain (domain 2) initiates a service acquisition request (carrying user token information) to the earth data resource service of the target domain (domain 1) through the cross-domain resource gateway;

[0085] 2) The target domain (domain 1) earth data resource service requests the unified user service to verify the identity information;

[0086] 3) The user service of the target domain (domain 1) requests addressing from the earth data resource directory of the domain (domain 1) and obtains the addressing result;

[0087] 4) The unified user service of the target domain (domain 1) requests the unified user service of the entire domain to verify the identity information (token verification) through the cross-domain resource gateway;

[0088] 5) The unified user service of the entire domain verifies the identity information and performs authentication control according to the identity authority, and then returns the result to the unified user service of the target domain (domain 1) through the cross-domain resource gateway;

[0089] 6) After the target domain (domain 1) unified user service obtains the return result, it returns the authentication result to the target domain (domain 1) earth data resource service;

[0090] 7) If the verification is successful and the requested service is within the user's authorization scope, the target domain (domain 1) earth data resource service will release the earth data resource service business request and return the earth data resource to the current domain (domain 2) terminal through the cross-domain resource gateway; if the verification is unsuccessful or the requested service is not within the user's authorization scope, the target domain (domain 1) earth data resource service will refuse to provide resource acquisition services, and the terminal in the current domain (domain 2) will not be able to obtain earth data resources.

[0091] In order to meet the requirements of cross-domain earth data resource acquisition in terms of network resources and acquisition efficiency, a set of adjustable resource location strategies are defined, and effective acquisition resources are dynamically updated according to environmental conditions during the use of earth data resources to complete the dynamic location of earth data resources without users' perception. Resource location strategies include efficiency-first access strategy (EFS), stability-first access strategy (SFAS), multi-factor balanced strategy (MFBS), access locked strategy to special resources (ALSSR), etc., which are obtained by combining a set of custom resource acquisition evaluation indicators to sort earth data resources. The higher the score, the more the earth data resource meets the resource location strategy. These resource acquisition indicators include Normalized Distance (ND), Normalized Response Time (NRT), Success Rate (SR), Resource Cross-domain Status (RCDS), and Resource Load Index (RLI). The value range of RCDS is 0 and 1, that is, RCDS of data within the domain is 0, and RCDS of cross-domain data is 1; the value range of RLI is 0 to 1, that is, the greater the load, the closer RLI is to 1, otherwise the closer RLI is to 0. EFS is an efficiency score after evaluating indicators such as resource distance, resource acquisition response time, resource cross-domain status, and resource current load index. It can be specifically expressed as

[0092]

[0093] Among them, α is a constant ranging from 0 to 1. SFAS is the stability score after evaluating indicators such as resource acquisition success rate, resource cross-domain status, and resource current load index. It can be specifically expressed as

[0094] SFAS=(α+RCDS)RCDS·SR·RLI

[0095] MFBS is a balance score after evaluating indicators such as resource distance, resource acquisition success rate, resource acquisition response time, resource cross-domain status, and resource current load index. It is a balance between network bandwidth occupancy, acquisition reliability, and acquisition efficiency. It can be specifically expressed as

[0096]

[0097] ALSSR refers to some special earth data resources that only provide services to specific users or clients, which is achieved by binding with user permissions. For other non-bound users, it is impossible to discover and use the earth data resources during cross-domain resource positioning.

[0098] (2) Hierarchical control of resource acquisition

[0099] Resource acquisition hierarchical control, hierarchical acquisition control of earth data resources, according to the differences in user roles and permissions, define the corresponding data acquisition strategy, and restrict the user's acquisition of earth data resources outside the scope of permission. The resource acquisition evaluation results are calculated by three indicators: user role level, operation risk level, and earth data resource criticality level. When the evaluation result is 1, access is allowed, and when it is 0, access is not allowed. User role level (User Level, UL) represents the level corresponding to the role of the user, distinguishing three categories of earth data resource administrator (Resource Administrator, RA), earth data resource producer (Resource Producer, RP), and earth data resource user (Resource User, RU). There is a possible role level value of 0.1, 0.5, and 0.9. Operation risk level (Operate Risk Level, ORL) represents the risk impact degree that the user's attempted resource acquisition operation may bring. The risk impact degrees corresponding to the four types of operations of resource acquisition, resource update, resource editing, and resource deletion are 0.1, 0.5, 0.8, and 0.9 respectively. The Resource Criticality Level (RCL) of earth data resources is determined based on factors such as the spatial resolution, shooting time, and data quality of earth data resources. The higher the spatial resolution, the later the shooting time, and the higher the data quality, the higher the criticality level. It can be obtained by weighting the expert scores. There are possible values ​​of 0.25, 0.5, 0.75, and 1. The Resource Access Score (RAS) can be expressed as

[0100]

[0101] In addition, the hierarchical access control of earth data resources also includes calculating the user access risk index (User Access Risk Level, UARL) based on the user's access behavior. For users with a higher risk index, the level of data that can be obtained is reduced. When the user's access behavior is too frequent, intervention is carried out to reduce the user's access level, restricting them to only access low-level public resources, and not to access important resources or core resources. When calculating the user access risk index, it is necessary to consider the user access frequency (User Access Frequency, UAF), access time (User Access Time, UAT), resource level (Resource Level, RL), etc. The user access risk index UARL corresponding to the i-th user i It can be expressed as

[0102]

[0103] Where N is the total number of earth data resources, M is the total number of earth data resources accessed by the i-th user, They respectively represent the acquisition frequency, acquisition duration, and resource level of the mth earth data resource accessed by the ith user.

[0104] 3. Hybrid backup mechanism for earth data resources

[0105] The hybrid backup mechanism for earth data resources comprehensively considers the acquisition efficiency and security factors in the process of backing up earth data resources, and adopts a hybrid earth data resource division strategy and replica migration strategy. A multi-node resource criticality division scheme is designed, and core key resources and restricted acquisition resources are stored locally. Basic public data resources and open shared data provide multi-node off-site master-slave functions. The design considers the differentiated replica migration process of data volume. Periodic incremental replicas are actively migrated across domains through the global directory service, and real-time differential replicas are passively migrated within the domain after the cross-domain acquisition of earth data resources is completed.

[0106] (1) Resource criticality division strategy

[0107] Resource criticality division strategy: core key resources and restricted access resources use local backup storage, and data backup nodes are set up in this domain. Different acquisition methods are selected based on the criticality of earth data resources, node distance, and resource positioning strategy results. When acquiring core key resources, priority is given to acquiring local master node data. When the master node data acquisition is abnormal, switch to the data of the local backup node. Basic public data resources and open shared data adopt a remote master-slave strategy, and set up data backup nodes in multiple different domains. When acquiring basic public data resources and open shared data, priority is given to acquiring local master node data. When the master node data acquisition is abnormal, data from backup nodes in other domains is acquired based on the cross-domain data service acquisition function. After selecting the node, the resource positioning strategy is adopted to select the most suitable earth data resource for access to provide efficient access.

[0108] (2) Differentiated copy migration process

[0109] First, the dynamic changes of the global earth data resource directory are detected at dynamic time intervals to extract incremental earth data resources, build incremental copies, and then synchronize the incremental copies to the backup nodes through the underlying data synchronization service to complete the periodic incremental copy migration process. Taking into account the characteristics of earth data resources such as frequent changes and large volume, the change detection time interval is dynamically adjusted according to the historical changes of earth data resources. For asynchronous data within the change detection interval (difference data discovered in real time through cross-domain acquisition), the difference data should be cached to the backup node after the cross-domain acquisition is completed, and the real-time difference copy migration process should be completed through real-time caching of the difference data. The specific process is as follows: Figure 5 As shown in the figure, the Resource Mean Change Detection Interval (RMCDI) is the dynamic result obtained by weighting different earth data resource update intervals (RCDI) according to the critical level in a certain period of time in the past. The RMCDI calculation method is:

[0110]

[0111] Among them, RCL i and RCDI i are the critical level and update interval of the i-th updated earth data resource, and M is the total number of updated earth data resources.

[0112] exist Figure 5In the periodic incremental copy migration, after a new earth data resource is added to domain A (domain 1), the earth data resource directory is updated and the service is published to the earth service resource directory; the earth data resource directory of domain A (domain 1) automatically synchronizes the metadata of the newly added data directory to the earth data resource directory of domain B (domain 2) through the service gateway agent; the newly added entity data of domain A (domain 1) is synchronized to domain B (domain 2), and the entity data is stored in the environment of domain B (domain 2) by calling the earth data resource directory service of domain B (domain 2), so as to realize the synchronization of incremental entity data; after the data synchronization is completed, it is automatically published in the earth service resource directory of domain B (domain 2) to provide service calls to the outside world.

[0113] exist Figure 5 In the real-time differential copy migration, when the service user of domain B (domain 2) obtains the earth data resource service, it addresses through the earth service resource directory and gives priority to obtaining the earth data resource service of the domain; in the case of missing data in domain B (domain 2), the earth data resource service published across domains in domain A (domain 1) is automatically obtained across domains, and the earth data resource service published across domains in domain A (domain 1) is automatically obtained across domains through the service gateway proxy. Through the reverse proxy of the service gateway, the acquisition request is mapped to the earth data resource service of domain A (domain 1); the earth data resource obtained from domain A (domain 1) is returned and stored in the data cache pool of domain B (domain 2) through the earth data resource service of domain B (domain 2), so that the returned data can be quickly responded to the next time it is obtained.

[0114] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A cross-domain sharing system for earth data resources, characterized in that: include: Earth data resource catalog service is used to perform structured analysis on earth data resources of different sources and types, extract core meta-information of earth data resources, and establish a unified earth data resource model using ontology technology; extract meta-information and semantic conversion of earth data resources from different sources through text data processing and cleaning methods, and instantiate the earth data resource model; associate and integrate earth data resources in each domain and the entire domain, build an earth data resource catalog, and establish a unique data identifier using data type, spatial range, spatial level, and time range; The cross-domain resource acquisition module is used to dynamically locate earth data resources while balancing resources and efficiency, and to achieve cross-domain efficient acquisition of earth data resources based on reverse proxy technology; Restrict users' cross-domain acquisition behaviors from two aspects: permission hierarchical control and risk behavior restriction, intercept user acquisition that exceeds the permission definition, and implement acquisition restrictions for acquisition behaviors with potential risks to ensure the security of cross-domain earth data resource acquisition; The hybrid backup mechanism of earth data resources is used to comprehensively consider the acquisition efficiency and security factors in the process of earth data resource backup, and provide a hybrid earth data resource partitioning strategy and replica migration strategy. The hybrid earth data resource partitioning strategy designs a multi-node resource criticality partitioning scheme. Core key resources and restricted access resources use local backup storage, and basic public data resources and open shared data use multi-node off-site master and backup. The replica migration strategy design takes into account the differentiated replica migration process of data volume. Periodic incremental replicas are actively migrated across domains through the global directory service, and real-time differential replicas are passively migrated within the domain after the cross-domain acquisition of earth data resources is completed.

2. The cross-domain sharing system for earth data resources according to claim 1 is characterized in that: The Earth Data Resource Directory Service includes two parts: Earth Data Resource Model and Cross-Domain Resource Publishing Service. The Earth data resource model conducts structured analysis on Earth data resources of different sources and types, extracts the core metadata of Earth data resources, and uses ontology technology to establish a unified model structure; through text information processing and cleaning operations, it extracts metadata and performs semantic conversion on Earth data resources in different domains, and completes the instantiation of the Earth data resource model, which includes: 1) Read the spatial coordinate system and time zone in the meta-information to complete the extraction of spatiotemporal reference information; 2) Read the origin and affine coefficients in the meta-information, calculate the spatial range, and complete the spatial information extraction; 3) Read the time version information in the meta information and complete the time information extraction; 4) Read the sensor identification, product level, reference system, projection parameters, and band in the meta-information to extract other attribute information; 5) Filling the earth data resource model with the information extracted in 1)-4) to complete the instantiation process of the earth data resource model; Cross-domain resource publishing service, establish the mapping relationship between the earth data resource model structure and the earth data resource directory at the attribute level; perform similarity analysis on earth data resources in different domains, associate and aggregate earth data resources with high similarity, and build a unified global earth data resource directory; use the data type, spatial range, spatial level, and time range of earth data resources to establish a unique identifier for earth data resources to ensure the uniqueness requirements of earth data resource discovery, including: Determine the content of the earth data resource directory and complete the attribute mapping. The earth data resource directory provides the ability to search and describe earth data resources in the entire domain and in each domain, including earth data resource identification, resource registration time, resource coverage, resource product level, and source unit information; map the earth data resource model structure with the earth data resource directory, map the spatial information in the earth data resource model to the resource coverage of the earth data resource directory, map the time information to the resource registration time, and map the product number to the resource product level; Use the spatial information and attribute information of earth data resources to establish data association, complete earth data resource aggregation, and calculate the spatial association and attribute association between different earth data resources registered in the earth resource directory. Spatial association is to calculate the spatial association between data from the spatial topological relationship and spatial distance measurement between the two data. Attribute association is to calculate the association of earth data resources from whether the attributes of different earth data resources match and whether the attribute values ​​are consistent; aggregate earth data resources with high spatial association and attribute association in the directory to provide unified resource acquisition capabilities; Establish a unique identifier for earth data resources, and sequentially concatenate the type code, Hilbert curve code, maximum spatial level, time code, and 4-bit random code of the earth data resources to form an identifier for the earth data resources.

3. The cross-domain sharing system for earth data resources according to claim 1 is characterized in that: The cross-domain resource acquisition system consists of two parts: the cross-domain earth data resource acquisition module and the resource acquisition hierarchical control module, among which: The cross-domain earth data resource acquisition module defines the cross-domain earth data resource acquisition process including the user authentication process. The forwarding of resource acquisition requests between domains is realized through the cross-domain resource gateway, which is realized by integrating external proxy services. The user authentication process is completed by integrating external unified user services. The process of users in the current domain cross-domain acquiring earth data resources in the target domain includes: 1) The terminal user in the current domain initiates a service acquisition request to the earth data resource service in the target domain through the cross-domain resource gateway, and the request carries the user token information; 2) The target domain earth data resource service requests the unified user service to verify the identity information; 3) The target domain user service requests addressing from the earth data resource directory of the domain and obtains the addressing result; 4) The target domain unified user service requests the unified user service of the entire domain to verify the identity information through the cross-domain resource gateway; 5) The unified user service of the entire domain verifies the identity information and performs authentication control according to the identity authority, and then returns the result to the unified user service of the target domain through the cross-domain resource gateway; 6) After the target domain unified user service obtains the return result, it returns the authentication verification result to the target domain earth data resource service; 7) If the verification is successful and the requested service is within the user's authorization scope, the target domain earth data resource service will release the earth data resource service business request and return the earth data resource to the current domain terminal through the cross-domain resource gateway; if the verification is unsuccessful or the requested service is not within the user's authorization scope, the target domain earth data resource service will refuse to provide resource acquisition services, and the terminal in the current domain will not be able to obtain earth data resources; The resource acquisition hierarchical control module defines the data acquisition strategy that matches the user roles and permissions, restricting the user's acquisition of earth data resources outside the scope of the permissions. Specifically, the resource acquisition evaluation results are calculated based on three indicators: user role level, operation risk level, and earth data resource criticality level. When the evaluation result is 1, access is allowed, and when it is 0, access is not allowed. Among them: The user role level UL represents the level of the user's role, including three categories: earth data resource administrator, earth data resource producer, and earth data resource user, with values ​​of 0.1, 0.5, and 0.9 respectively; the operation risk level ORL represents the risk impact of the resource acquisition operation that the user attempts to perform. The risk impact levels corresponding to the four types of operations, resource acquisition, resource update, resource editing, and resource deletion, are 0.1, 0.5, 0.8, and 0.9 respectively; the earth data resource criticality level RCL is determined based on the spatial resolution, shooting time, and data quality of the earth data resources. The higher the spatial resolution, the later the shooting time, and the higher the data quality, the higher the criticality level. It is obtained by weighting the expert scores, with values ​​of 0.25, 0.5, 0.75, and 1; the resource acquisition evaluation result is expressed as 4. The cross-domain sharing system for earth data resources according to claim 3 is characterized in that: The cross-domain earth data resource acquisition module defines a set of adjustable resource positioning strategies. Through the combination of resource acquisition evaluation indicators, it dynamically updates the effective acquisition resources according to environmental conditions and completes the dynamic positioning of earth data resources without users noticing. Resource location strategies include efficiency priority strategy EFS, stability priority strategy, multi-factor balance strategy, and special resource acquisition locking strategy. The earth data resources are ranked by the results obtained through a set of customized resource acquisition evaluation indicators. The higher the score, the more the earth data resource conforms to the resource location strategy. The resource acquisition evaluation indicators include normalized resource distance, normalized resource acquisition response time, resource acquisition success rate, resource cross-domain status, and resource current load index, which are expressed as ND, NRT, SR, RCDS, and RLI. The efficiency priority strategy is the efficiency score after evaluating the resource distance, resource acquisition response time, resource cross-domain status, and resource current load index, expressed as Among them, α is a constant ranging from 0 to 1; The stability priority strategy is the stability score after evaluating the resource acquisition success rate, resource cross-domain status, and resource current load index, expressed as SFAS = (α + RCDS) RCDS · SR · RLI The multi-factor balancing strategy is a balance score after evaluating resource distance, resource acquisition success rate, resource acquisition response time, resource cross-domain status, and resource current load index, expressed as The special resource acquisition locking strategy means that some special earth data resources only provide services to specific users or clients, which is achieved by binding with user permissions. Other non-bound users cannot discover and use the earth data resources during cross-domain resource positioning.

5. The cross-domain sharing system for earth data resources according to claim 3 is characterized in that: The resource acquisition classification control module also calculates the user acquisition risk index based on the user's acquisition behavior, and reduces the level of data that can be obtained for users with a higher risk index. When calculating the user acquisition risk index, the user's acquisition frequency, acquisition duration, and resource level are taken into account; User acquisition risk index UARL corresponding to the i-th user i It can be expressed as Where N is the total number of earth data resources, M is the total number of earth data resources accessed by the i-th user, They respectively represent the acquisition frequency, acquisition duration, and resource level of the mth earth data resource accessed by the ith user.

6. The cross-domain sharing system for earth data resources according to claim 1, characterized in that: The hybrid backup mechanism of earth data resources includes a hybrid earth data resource partitioning strategy and a replica migration strategy, wherein: A hybrid strategy for dividing earth data resources: core key resources and restricted access resources use local backup storage, and data backup nodes are set up in the domain. When acquiring core key resources, local master node data is obtained first. When the master node data is abnormally obtained, the data is switched to the local backup node data. Basic public data resources and open shared data use remote master and backup, and data backup nodes are set up in multiple different domains. When acquiring basic public data resources and open shared data, local master node data is obtained first. When the master node data is abnormally obtained, the data of backup nodes in other domains is obtained based on the cross-domain data service acquisition function. The replica migration strategy first detects the dynamic changes of the global earth data resource directory at dynamic time intervals to extract incremental earth data resources, build incremental replicas, and then synchronize the incremental replicas to the backup nodes through the underlying data synchronization service to complete the periodic incremental replica migration process. For asynchronous data within the change detection interval, the differential data should be cached to the backup node after the cross-domain acquisition is completed, and the real-time differential replica migration process is completed through the real-time caching of differential data.

7. The cross-domain sharing system for earth data resources according to claim 6, characterized in that: In the replica migration strategy, the detection time interval RMCDI is a dynamic result obtained by weighting the update intervals RCDI of different earth data resources by key levels within a certain period of time in the past. The calculation method is: Among them, RCL i and RCDI i are the critical level and update interval of the i-th updated earth data resource, and M is the total number of updated earth data resources.

8. A cross-domain sharing method for earth data resources, characterized in that: Using the cross-domain sharing system for earth data resources according to any one of claims 1 to 7, cross-domain sharing of earth data resources is realized, including: Using the earth data resource directory service, we can conduct structured analysis on earth data resources of different sources and types, extract the core meta-information of earth data resources, and use ontology technology to establish a unified earth data resource model; through text data processing and cleaning methods, we can extract meta-information and semantic conversion of earth data resources from different sources, and instantiate the earth data resource model; we can associate and integrate earth resource data in each domain and the entire domain, build an earth data resource directory, and establish a unique data identifier using data type, spatial range, spatial level, and time range; Using the cross-domain resource acquisition module, the earth data resources are dynamically located under the premise of balancing resources and efficiency, and the cross-domain efficient acquisition of earth data resources is realized based on the reverse proxy technology; the cross-domain acquisition behavior of users is restricted from two aspects: permission classification control and risk behavior restriction, and the user acquisition that exceeds the permission definition is intercepted. The acquisition restriction is implemented for the acquisition behavior with potential risks to ensure the security of cross-domain earth data resource acquisition; By using the hybrid backup mechanism of earth data resources and comprehensively considering the acquisition efficiency and security factors in the process of earth data resource backup, a hybrid earth data resource division strategy and replica migration strategy are provided. The hybrid earth data resource division strategy designs a multi-node resource criticality division scheme. The core key resources and restricted acquisition resources are stored locally, and the basic public data resources and open shared data are stored in multiple nodes in different locations. The replica migration strategy design considers the differentiated replica migration process of data volume. The periodic incremental replica is actively migrated across domains through the global directory service, and the real-time differential replica is passively migrated within the domain after the cross-domain acquisition of earth data resources is completed.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the cross-domain sharing system for earth data resources as described in claim 8 is implemented to realize cross-domain sharing of earth data resources.

10. A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the cross-domain sharing system for earth data resources according to claim 8 is implemented to realize cross-domain sharing of earth data resources.

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