KR101109549B1 - Apparatus and method for sensor node management based on metadata - Google Patents

Abstract

Disclosed are a sensor node management apparatus and method based on metadata. The address obtaining unit obtains the connection information of the data server corresponding to the identification code of the sensor node to be searched from an external device having the connection information of the data server storing metadata of the plurality of sensor nodes constituting the sensor network. The data acquisition unit accesses the data server corresponding to the obtained access information of the data server and acquires metadata corresponding to the identification code of the sensor node to be searched. The sensor node manager accesses a sensor node to be searched based on the information included in the metadata and transmits a control message. According to the present invention, since data related to a sensor node is stored in a separate data server instead of a sensor node with limited resources, the overhead of the sensor node due to storage and communication of data can be reduced, and data related to the sensor node can be easily facilitated. By transmitting the query message or control command to the sensor node by communicating with a sensor node having an identification code, it is possible to actively control the sensor network and utilize the sensor data.

Identification code, metadata, data server

Description

Apparatus and method for sensor node management based on metadata}

The present invention relates to an apparatus and method for managing a sensor node based on metadata, and more particularly, to retrieve metadata of a sensor node and to control the sensor node using an identification code assigned to the sensor node constituting the sensor network. An apparatus and method are provided.

Unlike the early sensor network used for a specific application purpose, many efforts have been made to easily add and use a sensor node having various physical information collection functions without prior knowledge of the sensor network. By describing the function of a sensor node in a predefined language that can be recognized by a computer, it is metadata that provides a functional specification of each sensor node in the form of an electronic manual. Background art on metadata includes the definition and exchange of metadata and the use of metadata.

Conventional techniques for sensor metadata include the IEEE 1451 standard, the ZigBee standard, and the SensorML standard. IEEE1451.5 of the IEEE1451 series of standards has defined a standard for utilizing Transducer Electronic Datasheets (TEDS), a kind of metadata in the ZigBee sensor network. The sensor node's configuration information is encoded in a binary form or written in text-based form, conforming to a standard template. TEDS is usually stored in the sensor node, but provides a way to store IEEE1451 TEDS on a server on the Internet using virtual TEDS.

SensorML defines a metadata model and XML encoding that describe various features of the sensor and measurement process—geographic, dynamic, and measurement. TinyML defines SensorML as a lightweight solution for embedded wireless sensor networks.

However, the binary form of TEDS is not flexible, incompatible, and text-based TEDS is not effective in the memory of embedded sensor nodes such as EEPROM. Storing metadata in resource-restricted sensor nodes requires a lot of storage space and wastes a lot of energy for transmitting metadata. Since SensorML and TinyML are focused on describing the characteristics of sensor nodes, they do not provide information and functional specifications about sensor node functions and message formats, so that metadata can be used without the prior knowledge of sensor nodes. Can not use it.

ZigBee, on the other hand, defines standard public application profiles that define messages, message formats and message processing actions, allowing developers to develop compatible applications using different sensors. However, communication between ZigBee devices relies on common application profiles, so sensor nodes that implement functions other than previously known application profiles or standards are not compatible. ZigBee's service discovery uses the DeviceURL field to indicate a URL that contains additional information about the sensor node, but this could not be automated because it requires web page browsing by humans. In addition, when the location of the metadata is changed, the DeviceURL stored in the ZigBee sensor node indicates a broken URL, thereby making it impossible to obtain additional metadata.

In addition, to remove the constraints that occur when metadata is stored inside the sensor node, you can configure the template of the sensor metadata and allow the template to be downloaded from an external database, or download the metadata from the directory server. Although the technology has been proposed, there has been a problem that the location must be known in advance in a centralized form in which the location of the database or directory server providing the template is fixed, and the scalability is poor.

Until now, the sensor network is a structure in which metadata and sensor data are provided together at a sensor node or a base station, or because the storage location of metadata must be known in advance even if metadata is acquired from the outside. It was a rescue. Metadata has different characteristics from data collected from sensor nodes. Since metadata is not a value dynamically generated at the sensor node, but a data describing the function, characteristics, and operation of the sensor node, the value does not change during the operation of the sensor node and is written in a high-level language such as XML for compatibility. Can be.

Tightly coupled architectures that do not take into account the characteristics of the metadata are tightly coupled to the sensor node or base station. Consider the characteristics of sensor nodes that require low power, low processing power, and limited memory. It is not effective in that it requires additional memory burden and consumes a lot of energy for transmitting metadata, and when the metadata is stored in the base station, the sensor node is dependent on a specific base station with metadata. It is limited in the mobility (mobility) of the.

In order to solve the above problems, a unique identification code system fixed to the sensor node is used, and based on the identification code, the access information of the data server in which data about the sensor node to be searched is stored is obtained. There is a need for a method of obtaining data corresponding to an identification code of a sensor node to be searched by connecting to a data server corresponding to access information of a data server. Furthermore, there is a need for a method of decoding metadata including a function specification to communicate with sensor nodes so that active control and sensor node data for the sensor network can be utilized through transmission of a control mesh.

The technical problem to be achieved by the present invention is to avoid the additional memory usage and communication overhead between nodes, and to overcome the disadvantage that dynamic update is impossible, the meta data of the sensor node stored in the data server based on the identification code uniquely assigned to the sensor node. The present invention provides a sensor node management apparatus and method based on metadata for acquiring data and managing sensor nodes based on information included in the metadata.

Another technical problem to be solved by the present invention is a sensor node stored in a data server based on an identification code uniquely assigned to a sensor node in order to avoid additional memory usage and inter-node communication overhead, and to overcome the disadvantage that dynamic update is impossible. To provide a computer-readable recording medium recording a program for acquiring the data of the data and executing the sensor node management method based on metadata that can manage the sensor node based on the information contained in the metadata. have.

In order to achieve the above technical problem, the sensor node management apparatus based on metadata according to the present invention is retrieved from an external device having access information of a data server storing metadata of a plurality of sensor nodes constituting a sensor network. An address obtaining unit for obtaining access information of a data server corresponding to an identification code of a target sensor node; A data acquisition unit accessing a data server corresponding to the obtained access information of the data server and acquiring metadata corresponding to the identification code of the sensor node to be searched; And a sensor node manager which accesses the searched sensor node and transmits a control message based on the information included in the metadata.

In order to achieve the above technical problem, the method for managing a sensor node based on metadata according to the present invention is to search from an external device having access information of a data server storing metadata of a plurality of sensor nodes constituting a sensor network. An address acquisition step of acquiring access information of the data server corresponding to the identification code of the target sensor node; A data acquiring step of accessing a data server corresponding to the acquired access information of the data server and acquiring metadata corresponding to the identification code of the sensor node to be searched; And a sensor node management step of accessing the search target sensor node and transmitting a control message based on the information included in the metadata.

According to an apparatus and method for managing a sensor node based on metadata according to the present invention, since data related to a sensor node is stored in a separate data server instead of a sensor node with limited resources, an overhead of a sensor node according to data storage and communication Can be reduced, and data related to the sensor node can be easily obtained. In addition, when modifying registered data or adding new data, it is possible to connect to a data server and update data for a plurality of sensor nodes collectively. Furthermore, by communicating with a sensor node having an identification code according to the function specification of the acquired metadata, an inquiry message or a control command is transmitted to the sensor node, whereby active control of the sensor network and utilization of the sensor data are possible.

Hereinafter, exemplary embodiments of an apparatus and method for managing a sensor node based on metadata according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing the configuration of a preferred embodiment of a sensor node management apparatus according to the present invention.

Referring to FIG. 1, the sensor node management apparatus 100 according to the present invention includes an identification code extractor 110, an address acquirer 120, a data acquirer 130, and a sensor node access information storage 140. And a sensor node manager 150.

The address acquisition unit 120 accesses a sensor node to be searched based on a unique identification code assigned to each of the plurality of sensor nodes constituting the sensor network, and access information of a data server storing metadata of the sensor node to be searched. Acquire it. In this case, the identification code is preferably fixed to each of the sensor nodes.

There are two types of data used in the sensor network: data collected at the sensor node and predefined metadata. Data collected from sensor nodes are sensor data that collects physical state information in response to a specific period or a specific event, and information dynamically obtained from the sensor node for management purposes such as location information or battery level. On the other hand, metadata is data necessary for the sensor node to describe the service, function, and characteristics of the sensor node and is static additional information that does not change during operation of the sensor node. For example, the metadata may include information about a sensor collecting specific physical data, a function provided by a sensor node, and a communication format, in order to utilize data collected from a sensor node or a wireless sensor network.

Metadata of sensor node includes data about sensor object such as sensor type, sensor unit, operating system type and version of sensor, power consumption conversion information, sensor node manufacturer, etc. Contains data about the format of the message. Table 1 below describes the types and examples of metadata.

Metadata Classification Example of metadata sensor Sensor type, sensing unit, effective range, sensitivity,
Calibration information, manufacturer, etc. Sensor node List of sensors, hardware / software / network information,
Duty cycle, battery model and information Sensor data Event information, event setting information, service list provided,
Message format by service Applications Sensor node images, icons, etc.

When metadata is stored inside the sensor node, additional sensor node overhead is generated for storage and transmission in order to obtain metadata, which is a functional specification of the sensor node. Therefore, the metadata is stored in a separate data server rather than a sensor node, and the data server is distributed and located in a network on the Internet.

As the data server storing metadata is configured separately from the sensor node, the metadata does not need to be stored in each sensor node, and in order to obtain the metadata, an identification code uniquely assigned to each sensor node is obtained. Acquiring the data is easy because the access information of the data server is acquired based on the data server. In addition, when modifying registered data or adding new data, it is possible to connect to a data server and update data for a plurality of sensor nodes collectively.

In order to link metadata stored in a distributed sensor metadata server with a sensor node, a method for uniquely identifying the metadata and the sensor node is required. The network address used in the sensor network such as ZigBee is dynamically changed according to the topology, so the sensor metadata and sensor node cannot be uniquely identified, and the IPv6 address used in MAC address and 6LowPan also fixedly identifies a single sensor node. It is not possible to work with metadata servers. The address schemes used in the existing sensor network cannot identify the sensor node with a fixed and unique address or look up or resolve the connection information of the data server where the data is stored. Used separately.

As identification code, sensor node can be uniquely identified regardless of time and place such as EPC or OID, and code assignment is composed of hierarchical structure or tree structure, so that lookup of metadata server is possible. . By assigning and storing a unique code to the sensor node, the sensor node is uniquely identified and transmitted along with data collected from the sensor node when the sensor data is transmitted.

If the identification code assigned to the sensor node is already stored in the sensor node management apparatus 100 according to the present invention, the stored identification code may be used to access the sensor node. However, if the identification code is not stored in advance, the identification code transmitted with the sensor data should be extracted. To this end, the sensor node management apparatus 100 according to the present invention may include an identification code extraction unit 110. Since the data transmitted from the sensor node includes the identification code and the data collected from the sensor, the identification code extraction unit 110 extracts the identification code from the transmitted data and provides it to the address acquisition unit 120.

The address acquisition unit 120 may directly access a sensor node to obtain an address of a data server in which metadata of the sensor node is stored. As described above, in case of directly acquiring an address of a data server from a sensor node, there is an advantage in that a separate device is not required for acquiring an address, but there is a problem in that an overhead may be generated by additionally including a pointer to the sensor node. Therefore, there is a need to use a separate device that can obtain the address of the data server based on the identification code of the sensor node.

Accordingly, the address acquisition unit 120 may obtain the address of the data server by accessing the naming server that stores the address of the data server. That is, the address acquisition unit 120 accesses a naming server in which connection information of a data server storing metadata of a plurality of sensor nodes constituting a sensor network is stored corresponding to a unique identification code assigned to each sensor node. To obtain the address of the data server corresponding to the identification code of the sensor node to be searched.

When using a naming server, it is not necessary to connect to the sensor node to obtain the address of the data server. Instead, the address acquisition unit 120 accesses the naming server and obtains the address of the data server corresponding thereto by providing an identification code assigned to the sensor node. In the database of the naming server, the address of the data server is stored corresponding to each identification code assigned to each of the plurality of sensor nodes.

When building a database by storing the address of the data server inside the naming server, you can simply store the identification code and the address of the data server in a one-to-one correspondence. It is easy when searching for an address. For this purpose, the identification code must contain these classification criteria. For example, by including manufacturer information or product information of a sensor node in an identification code, identification codes of sensor nodes having the same manufacturer information or product information among a plurality of sensor nodes may be classified and stored separately. In addition, the classification criteria may be plural, and when there are a plurality of classification criteria, the identification codes may be classified and stored in a hierarchical manner by dividing them into upper and lower standards.

In this way, if the universal code such as EPC is used among the identification codes including a plurality of classification criteria, the uniqueness of the identification code can be guaranteed, so that the identification code is assigned to each sensor node and based on the data server. It is easy to sort and store addresses. EPC is a code system created by the international organization EPCglobal to integrate existing code systems. An example of an EPC configuration is shown in FIG. Referring to FIG. 2, the identification code includes header information, manufacturer information of a sensor node, product information of a sensor node, and a serial code. The information included in the code can be configured in various forms in consideration of convenience of use and issuance and management of the code. When the EPC configuration shown in FIG. 2 is used as an identification code, after classifying addresses of data servers corresponding to a plurality of identification codes based on the manufacturer information of the sensor node as a higher standard, the product information of the sensor node is used as a lower standard. You can reclassify the address of the data server based on. An example of classifying and storing the address of the metadata server among the data servers using the sensor node manufacturer information and the product information as the upper standard and the lower standard is shown in Table 2 below.

Manufacturer Information product information Metadata server address
A company
temperature Senser  http://icu.com/aaa Pressure sensor  http://icu.com/aab Light sensor  http://icu.com/aac
Company B
temperature Senser  http://icu.com/bba Pressure sensor  http://icu.com/bbb Light sensor  http://icu.com/bbc
Company C
temperature Senser  http://icu.com/cca Pressure sensor  http://icu.com/ccb Light sensor  http://icu.com/ccc

When the address acquisition unit 120 accesses the naming server and provides an identification code including the classification criteria of the metadata server address, the naming server extracts the classification criteria from the identification code and stores the address of the metadata server as shown in Table 2 below. Search the address of the metadata server corresponding to the identification code input from the address acquisition unit 120 in the database. In this case, when there are a plurality of classification criteria included in the identification code, the classification criteria corresponding to the upper criteria are first extracted and searched. Referring to Table 2, for example, if the identification code of the sensor is entered in the naming server to obtain the address of the metadata server in which the metadata of the temperature sensor manufactured by Company B is stored, the naming server is the first manufacturer The information is extracted from the identification code to retrieve a group of metadata server addresses classified as Company B. Next, the product information, which is a lower standard, is extracted from the identification code to search the address of the metadata server corresponding to the temperature sensor.

The process of obtaining the address of the data server corresponding to the identification code from the naming server is called resolving, and the address obtaining unit 120 may obtain the address of the data server by the above-mentioned method. The resolving method used to obtain the address of the data server from the naming server. For example, when an identification code of a sensor node has a hierarchical structure such as an EPC, an object naming service (ONS) may be used as one method of resolving.

ONS is a framework for providing information location of products corresponding to EPCs stored in RFID tags in a manner similar to the domain name service (DNS) that specifies the location of computers on the Web. ONS operates on the DNS framework, and a general procedure for ONS queries is shown in FIG. Referring to FIG. 3, when an RFID reader reads an EPC composed of a bit sequence stored in an RFID tag and sends it to a local server, the local server changes the EPC to a Uniform Resource Identifier (URI), and the local ONS resolver resolves the URI. Perform DNS query by changing to domain name. The DNS returns, as a response, the URL corresponding to the result of the query among the stored URLs.

When the above procedure is applied to the process of obtaining the metadata server's address from the naming server, the naming server changes the identification code of the EPC type to the URI, and then changes the URI to the domain name. Find the matching address among the stored metadata server's addresses. Next, the naming server outputs the address of the retrieved metadata server as a response and provides the address acquisition unit 120. 4 illustrates a process in which the address obtaining unit 120 obtains an address of the metadata server by providing an identification code assigned to the sensor node to the naming server.

If the response output from the naming server is output in the form of an A record consisting solely of IP addresses, it cannot be applied to advanced web service resolving. Therefore, the naming server outputs the response as a NAPTR record having a plurality of fields to indicate a protocol, a service, and the like. Table 3 below shows the NAPTR record response output from the naming server.

Order Pref Flag Service Regexp Desc. 0 2 u EPC + ws ! ^. * $! http: //icu.com/widget.wsdl! EPC 0 One u EPC + epcis ! ^. * $! http: //icu.com/epcis.php! EPC 0 3 u EPC + html ! ^. * $! http: //icu.com/things.asp! EPC 0 4 u EPC + mlrpc ! ^. * $! http: //icu.com/example.com! EPC 0 5 u EPC + x + metadata ! ^. * $! http: //epc.onlinesensors.net/product/000024/index.html! " metadata 0 One u EPC + x + metadata ! ^. * $! http: //epc.onlinesensors.net/metadata_exchanges.asmx? WSDL! " metadata 0 2 u EPC + x + metadata ! ^. * $! http: //epc.onlinesensors.net/metadata_exchanges.asmx/things! " metadata

Referring to Table 3, the order field and the pref field have integer values. A 'u' in the flag field means that the response contains a URI. The service field indicates a type of service and may have various types according to services supported by a server such as html, XMLRPC, EPC information service (EPCIS), and web service (WS). Regexp means that the address is expressed as a regular expression. Therefore, the URL representing the retrieved metadata server address is output in the form of regular expression.

The original function of ONS is to obtain the address of the server that stores the information of the RFID tagged product from the EPC read by the RFID reader. However, in the present invention, what the address acquisition unit 120 wants to acquire from the naming server is the address of the server where the data of the sensor node is stored, not the information of the tagged object.

Therefore, in order to prevent such confusion and to clarify that the naming server's response indicates the address of the sensor data server or the metadata server, the access information of the data server may be added as a type of service constituting the service field of the NAPTR record. . Therefore, the part indicated as 'EPC + x-metadata' in the service field among the NAPTR record responses shown in Table 3 means that the outputted response provides the connection information of the metadata server, and the address indicated by the regular expression is the address of the metadata server. It indicates that. Also, if a service type indicating the address of the sensor data server is added to the service field, it means that the outputted response provides connection information of the sensor data server.

When the address obtaining unit 120 obtains the address of the data server directly from the sensor node or obtains the address of the data server from the naming server, the data obtaining unit 130 accesses the data server located at the address to obtain the stored data. do. In the data server, data is classified and stored in groups according to appropriate criteria, and all data or only data of a group selected as needed can be obtained. As an example, FIG. 5 illustrates an example of an interface in which the data obtaining unit 130 queries and responds to metadata to be obtained from the metadata server. In order to access the metadata server, query messages can be defined using communication protocols such as TCP and UDP, or SOAP, an Internet protocol, or HTTP, can be used.

The sensor node manager 150 accesses a sensor node to be searched based on the information included in the metadata and transmits a control message. In order to transmit the control message, the sensor node should be connected to a search target sensor node. In this case, an identification code included in data transmitted from the sensor node may be used.

When accessing a sensor node using an identification code, a broadcast message including a target identification code may be transmitted to communicate with a sensor node corresponding to the identification code. However, there is a problem that additional overhead may occur in communication between sensor nodes due to the length of the identification code included in each transmission message. Because the identification code is fixed and assigned to the sensor node and is unique worldwide, it is very long when compared to the sensor network address that is used only temporarily inside the sensor node. Can be a constraint on the phase. Also, because the identification code is not an address, it cannot be used for direct unicast communication with the sensor node.

Therefore, in order to actually connect to the sensor node using the identification code, the identification code is converted into a network address for routing between sensor nodes, for example, a network address of ZigBee, or a short length that can shorten the length of the communication message between sensor nodes as much as possible. It should be converted into the identification code of and communicated. The short length identification code is fixed to the sensor node and, unlike the uniquely assigned identification code around the world, is guaranteed to be unique only within the sensor network. In a preferred embodiment, a short identification code consisting of a natural number is sequentially assigned to a sensor node having a unique identification code fixedly assigned to the sensor node, and a corresponding table is configured, so that the actual communication between the sensor network nodes is performed at the sensor node. Instead of a fixed, uniquely assigned unique identification code, a short, uniquely unique identification code of natural numbers may be used.

To this end, the sensor node management apparatus 100 according to the present invention may further include a sensor node access information storage unit 140 for this purpose. The sensor node manager 150 obtains the connection information of the searched sensor node corresponding to the identification code from the sensor node connection information storage 140 to access the searched sensor node. The unique identification code assigned to the sensor node and the access information for the corresponding network address or short length identification code are registered in the sensor node access information storage 140, and the network address of the sensor node is changed or the topology is changed. Each time it changes, the sensor node is dynamically updated on request.

When the sensor node is connected to the sensor node to transmit a query message or a control command to the searched sensor node, the connection information corresponding to the identification code of the sensor node may be obtained from the conversion table stored in the sensor node connection information storage 140.

FIG. 6 illustrates an example of a format of a query message to be transmitted to a sensor node among metadata obtained from a metadata server.

Meanwhile, an example of a message included in metadata when a sensor node is a zigbee device is as follows.

<Message>

<? xml version = "1.0" encoding = "UTF-8"?>

<profile>

<Identifier>

<type> SGTIN-96 </ type>

<value> 307427D58B0D47C000000001 </ value>

</ Identifier>

<NodeDescriptor>

<LogicalType description = "ZigBee end device"> 010 </ LogicalType>

<ComplexDescriptorAvailable description = "true"> 1 </ ComplexDescriptorAvailable>

<UserDescriptorAvailable description = "true"> 1 </ UserDescriptorAvailable>

<Reserved description = "reserved"> 0 </ Reserved>

<APS_Flags description = "APS_Flag"> 0 </ APS_Flags>

<FrequencyBand description = "902-928MHz"> 2 </ FrequencyBand>

<MAC_CapabilityFlags description = "FFD, main powers, disabled receiver during idle periods, no security"> 7 </ MAC_CapabilityFlags>

<ManufacturerCode description = "sample manufacturer"> 0x02 </ ManufacturerCode>

<MaximumBufferSize description = "0x7ff"> 0x7ff </ MaximumBufferSize>

<MaximumIncomingTransferSize description = "0x7fff"> 0x7fff </ MaximumIncomingTransferSize>

<ServerMask description = "Primary Trust Center"> 1 </ ServerMask>

<MaxiumOutgoingTransferSize description = "0x7fff"> 0x7fff </ MaxiumOutgoingTransferSize>

<DescriptorCapabilityField description = "0"> 0 </ DescriptorCapabilityField>

</ NodeDescriptor>

<NodePowerDescriptor>

<CurrentPowerMode

description = "Receiver synchronized with the receiver on when idel sub-field of the node descriptor."> 0000 </ CurrentPowerMode>

<AvailablePowerSource description = "Disposable battery"> 2 </ AvailablePowerSource>

<CurrentPowerSource description = "Rechargeable battery"> 1 </ CurrentPowerSource>

<CurrentPowerSourceLevel description = "33%"> 0100 </ CurrentPowerSourceLevel>

</ NodePowerDescriptor>

<SimpleDescriptor>

<EndPoint description = "10"> 10 </ EndPoint>

<ApplicationProfileIdentifier description = "Home Automation Profile Specification"> 0x0104 </ ApplicationProfileIdentifier>

<ApplicationDeviceIdentifier description = "ZCL_HA_DEVICEID_ON_OFF_SWITCH"> 0x0000 </ ApplicationDeviceIdentifier>

<ApplicationDeviceVersion description = "Ver0.8"> 0011 </ ApplicationDeviceVersion>

<ApplicationInputClusterCounter description = "one"> 1 </ ApplicationInputClusterCounter>

<ApplicationInputClusterList description = "ZCL_HA_CLUSTER_ID_GEN_BASIC"> 0x0000 </ ApplicationInputClusterList>

<ApplicationOutputClusterCount description = "one"> 1 </ ApplicationOutputClusterCount>

<ApplicationOutputClusterList description = "ZCL_HA_CLUSTER_ID_GEN_ON_OFF"> 0x0006 </ ApplicationOutputClusterList>

</ SimpleDescriptor>

<ComplexDescriptor>

<LanguageAndCharacterSet>

<LanguageCode description = "Korean"> en </ LanguageCode>

<CharacterSetIdentifier description = "ASCII character set"> 0x00 </ CharacterSetIdentifier>

</ LanguageAndCharacterSet>

<ManufacturerName description = "online sensors company"> online sensors company </ ManufacturerName>

<ModelName description = "ants-zigbee-98"> ants-zigbee-98 </ ModelName>

<SerialNumber description = "1"> 1 </ SerialNumber>

<DeviceURL description = "http://onlinesensors.net"> http://onlinesensors.net </ DeviceURL>

<Icond />

<IconURL> http://onlinesensors.net/sample/icons </ IconURL>

<presentation />

<presentationURL> http://onlinesensors.net/sample/node1.jpg </ presentationURL>

</ ComplexDescriptor>

<UserDescription />

</ ZigBeeDescriptor>

<Devices>

<Clusters>

<ServerSide>

<Cluster name = "On / Off">

<option> Mandatory </ option>

<Server>

<AttributeSetList>

<AttributeSet>

<AttributesList>

<Attributes>

<Identifier> 0x0000 </ Identifier>

<Name> OnOff </ Name>

<Type> Boolean </ Type>

<Range> 0x00-0x01 </ Range>

<Access> Read only </ Access>

<Default> 0x00 </ Default>

<Option> Mandatory </ Option>

<Value description = "On"> 1 </ Value>

<Value description = "Off"> 0 </ Value>

</ Attributes>

</ AttributesList>

<CommandsReceived>

<Commands>

<Identifier> 0x02 </ Identifier> <Description> Toggle </ Description> <Option> Mandatory </ Option>

<Payload> </ Payload>

</ Commands>

</ CommandsReceived>

</ Server>

</ Cluster>

</ ServerSide>

</ clusters>

</ devices>

</ profile>

Referring to the above message, the metadata includes three blocks, an <identifier> block, a <ZigBeeDescriptor> block, and a <device> block. <identifier> represents EPC information and shows type and identifier assigned to sensor node. The <ZigBeeDescriptor> block contains the contents of all the static Descriptors defined in ZigBee. Existing ZigBee defines two mandatory Descriptors and three optional Descriptors as Descriptors. Through Service Discovery provided by ZigBee, these Descriptors can be requested to specific sensor nodes and the contents of Descriptors can be received. However, non-static data among Descriptors, that is, values that should be dynamically collected from the sensor node such as the power level field of node power descriptors, are not included in the metadata. The <ZigBeeDescriptor> block describes the characteristic content of the sensor node. In particular, the <ZigBeeDescriptor> block contains the Profile ID, List, and Endpoint of the input cluster and output cluster.

The <device> block shows the functional specification information implemented in the sensor node. In particular, in the ZigBee example, the <device> block describes the cluster implemented in the sensor node. ZigBee cluster library (ZCL) is a collection of clusters that can be reused regardless of the various functions used in the application. The <device> block contains attributes and commands. The sensor node corresponding to the above message is a sensor node with On / Off switch actuating function, has On / Off attribute representing the state, and defines a Toggle command to change the state of the switch.

Sensor node management apparatus 100 according to the present invention can optionally show the operation specification of the metadata and implement a GUI that receives the user's input, using the attributes or commands of the metadata through the user's input or automated script Can be. In particular, in ZigBee, the metadata of the On / Off switch of the above message defines attributes and unique command identifiers for each command. In the ZigBee stack, standard commands and By providing a frame format, it is possible to communicate with sensor nodes based on metadata information.

7 is a ZigBee specification standard ZCL (ZigBee Cluster Library) frame format for communicating with sensor nodes using attributes and commands described in metadata. Since the standard frame format is defined and the meaning of each field is standard, the sensor node implementing ZigBee can communicate in the corresponding frame format. However, the contents of the frame format depend on the functions provided by the sensor node. Because it is different, the metadata is decoded to construct a frame and send it to the sensor node using values appropriate for specific attributes and commands.

8 is an example of a message that follows the frame format of FIG. This is an example of a user sending a toggle command to a ZigBee-based light sensor node. By referring to the metadata of the switch sensor node, the function specification provided by the light sensor node is identified, and the ZCL command is configured according to user input or automated script. By decoding the metadata, we can see that the device is a light device and provides a toggle command. To use the toggle command, the identifier and other information of the toggle command (Endpoint, cluster ID, APS profile ID, APS Src Endpint, APS). command) can be obtained. Accordingly, a message frame having a toggle command can be configured according to the frame format of FIG. 8. In this example, APS Dest Endpoint = 0x0A, APS cluster ID = 0x06, APS profile ID = 0x0400, APS Src Endpint = 0x01, and the APS payload command is 0x02.

As described above, the message sent to the search target sensor node may be transmitted based on a unique identification code fixed to the search target sensor node, and when the sensor node access information storage unit 140 is used, the search target In order to reduce the size of a network address or a message of a sensor node, a short identifier assigned to the sensor node may be transmitted as a receiving identifier to a search target sensor node.

As described above, when the sensor node management apparatus 100 according to the present invention is used, not only the metadata is obtained from the data server based on the identification code assigned to the sensor node, but also the sensor is based on the information included in the acquired metadata. The sensor network can be actively used by sending the appropriate query message or control command to the node.

9 is a flowchart illustrating a preferred embodiment of a method for managing a sensor node based on metadata according to the present invention.

Referring to FIG. 9, when a unique identification code assigned to a search target sensor node is not stored in advance among the plurality of sensor nodes constituting the sensor network, the identification code extracting unit 110 may perform a search on the sensor node. The identification code assigned to the search target sensor node is extracted from the transmitted data (S910). Next, the address acquisition unit 120 accesses a naming server in which connection information of a data server storing metadata of a plurality of sensor nodes is stored corresponding to an identification code assigned to each sensor node to identify a sensor node to be searched. Access information of the data server corresponding to the code is obtained (S920).

In this case, if the identification code includes manufacturer information or product information of the sensor node, the naming server stores the address of the data server using at least one of the information included in the identification code as a classification criterion. In the case of multiple classification criteria, the classification of the data server is classified hierarchically by dividing each classification criteria into upper and lower criteria.

Next, the data obtaining unit 130 accesses the data server corresponding to the obtained access information of the data server and acquires metadata corresponding to the identification code of the sensor node to be searched for (S930). Finally, the sensor node manager 150 transmits an inquiry message or a control command to the sensor node to be searched by using information included in the acquired metadata, that is, a communication message format (S940).

The present invention can also be embodied as computer-readable codes on a computer-readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, and may be implemented in the form of a carrier wave (for example, transmission via the Internet) . The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific preferred embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

1 is a block diagram showing the configuration of a preferred embodiment of a sensor node management apparatus according to the present invention;

2 is a view showing an example of a unique identification code assigned to a sensor node,

3 is a diagram illustrating a general execution procedure for an ONS query;

4 is a diagram illustrating a process of obtaining an address of a metadata server by providing an identification code assigned to a sensor node to a naming server by the address obtaining unit;

5 is a diagram illustrating an example of an interface where a data acquisition unit queries and responds to metadata to be obtained from a metadata server;

6 is a diagram illustrating an example of a format of a query message to be transmitted to a sensor node among metadata obtained from a metadata server;

7 illustrates a ZigBee specification standard ZCL (ZigBee Cluster Library) frame format for communicating with a sensor node using attributes and commands described in metadata.

8 is a diagram illustrating an example of a message conforming to the frame format of FIG. 7;

9 is a flowchart illustrating a preferred embodiment of a method for managing a sensor node based on metadata according to the present invention.

Claims (21)

An address obtaining unit for obtaining access information of a data server corresponding to an identification code of a sensor node to be searched from an external device having access information of a data server storing metadata of a plurality of sensor nodes constituting a sensor network; A data acquisition unit accessing a data server corresponding to the obtained access information of the data server and acquiring metadata corresponding to the identification code of the sensor node to be searched; And And a sensor node manager for extracting a format of an application message for communicating with the searched sensor node from the metadata and transmitting a control message to the searched sensor node. The method of claim 1, The external device is a sensor node management device, characterized in that the access information of the data server is stored in correspondence with a unique identification code assigned to each sensor node. The method of claim 1, The external device is a sensor node management device, characterized in that the search target sensor node. The method according to claim 1 or 2, And a sensor node access information storage unit, in which access information of the sensor node to be searched is stored corresponding to an identification code assigned to the sensor node to be searched. The method according to claim 1 or 2, Sensor node management apparatus further comprises an identification code extraction unit for extracting a unique identification code assigned to the search target sensor node from the data transmitted from the search target sensor node. 3. The method of claim 2, The identification code includes at least one of manufacturer information of the sensor node and product information of the sensor node, And the naming server stores the access information of the data server based on at least one of information included in the identification code as a classification criterion. The method of claim 6, The address obtaining unit obtains a response in the form of a record including the access information and the service field of the data server represented by a regular expression from the naming server, Sensor node management apparatus, characterized in that the connection information of the data server is recorded in the service field. 3. The method of claim 2, The identification code includes manufacturer information, sensor type information and unique code of the sensor node, The naming server sensor node management apparatus, characterized in that the access information of the data server corresponding to each sensor node is classified and stored hierarchically by the manufacturer information and sensor type information included in the identification code. The method according to claim 1 or 2, And the sensor node manager decodes a format of an application message for communicating with the search target sensor node among information included in the metadata and transmits the format of the application message to the search target sensor node. The method according to claim 1 or 2, The sensor node manager determines the functional specification provided by the search target sensor node based on the metadata, and configures the control message for controlling the operation of the search target sensor node according to a user input or an automated script. Sensor node management device, characterized in that. An address acquisition step of acquiring access information of a data server corresponding to an identification code of a sensor node to be searched from an external device having access information of a data server storing metadata of a plurality of sensor nodes constituting a sensor network; A data acquiring step of accessing a data server corresponding to the acquired access information of the data server and acquiring metadata corresponding to the identification code of the sensor node to be searched; And And a sensor node management step of extracting a format of an application message for communicating with the searched sensor node from the metadata and transmitting a control message to the searched sensor node. The method of claim 11, The external device is a sensor node management method, characterized in that the access information of the data server is stored in correspondence with a unique identification code assigned to each sensor node. The method of claim 11, The external device is a sensor node management method, characterized in that the search target sensor node. The method of claim 11 or 12, In the sensor node management step, the search target sensor node based on the access information obtained from the sensor node access information storage unit in which the connection information of the search target sensor node is stored corresponding to the identification code assigned to the search target sensor node. Sensor node management apparatus characterized in that connected to. The method of claim 11 or 12, And an identification code extracting step of extracting a unique identification code assigned to the searched sensor node from data transmitted from the searched sensor node. The method of claim 12, The identification code includes at least one of manufacturer information of the sensor node and product information of the sensor node, And the naming server stores the access information of the data server based on at least one of information included in the identification code as a classification criterion. The method of claim 16, In the address acquisition step, obtain a response in the form of a record including a service field and the access information of the data server expressed in a regular expression from the naming server, And the access information of the data server is recorded in the service field. The method of claim 12, The identification code includes manufacturer information, sensor type information and unique code of the sensor node, The naming server is a sensor node management method characterized in that the access information of the data server corresponding to each sensor node is classified and stored hierarchically by the manufacturer information and sensor type information included in the identification code. The method of claim 11 or 12, In the sensor node management step, the sensor node management method, characterized in that for decoding the format of the application message for communicating with the search target sensor node from the information contained in the metadata to the search target sensor node. The method of claim 11 or 12, In the sensor node management step, the control message for grasping the functional specification provided by the search target sensor node based on the metadata and controlling the operation of the search target sensor node according to a user input or an automated script. Sensor node management method comprising the configuration. A computer-readable recording medium having recorded thereon a program for executing the sensor node management method according to claim 11 or 12.

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