KR20100070100A - Method for updating sensor node based on database and method for operating target-node - Google Patents

Abstract

PURPOSE: A node updating method based on a database and a target node operating method thereof are provided to update an image of a sensor node by communicating only delta information consisting of difference between a present execution image and an image to update of the sensor node. CONSTITUTION: A database storing a node identifier and an execution image about each node is constructed. The execution image of a target node from the database is extracted by using an identifier of the target node(S330). The similarity of data between the execution image and an updating image is compared with reference to an address field. The data includes a record of the updating image which is not similar. Delta information is generated(S350).

Description

Database-based node update method and target node operation method {Method for updating sensor node based on database and method for operating target-node}

The present invention relates to a method for updating a sensor node constituting a sensor network. Specifically, a node update for updating a node by transmitting difference information between an image to be updated and an execution image based on a database of execution images of each sensor node. It relates to a method and a target node operation method accordingly.

The present invention is derived from a study conducted as part of a research-based project of the Ministry of Knowledge Economy and the Korea Institute of Information and Telecommunication Research and Development. [Task Management No .: 07-Base-10, Project Name: Daegu Embedded S / W Technical Support Center].

Recently, due to the development of wireless communication technology and the development of hardware technology, a small sized wireless communication node has been developed at a low price, and research on the wireless sensor network has been actively conducted as one of the applications using the wireless communication node.

The wireless sensor network consists of a sink node that collects data and processes it into necessary information, and a sensor node that collects data of interest with a sensor. These sensor nodes are placed in dangerous places, often called human sensor fields, to collect data of interest and transmit the collected data to the server through the sink node.

Typically, these sensor nodes are mainly deployed in places where human activity or access is not easy, and when the execution image of the sensor node needs to be modified, these positional factors cause the sensor node to go directly to the place where the sensor node is placed. It is very difficult to modify the executable image by collecting it or communicating over the wired interface.

Therefore, it is necessary to update the execution image of the sensor node through wireless communication. In the conventional execution image update method using wireless communication, since the execution image to be updated must be transmitted as a whole and downloaded and updated from each node, there is a problem in that the amount of data to be transmitted increases and the wireless communication amount increases, and the sensor node itself. There is a problem that must have a large amount of memory for image replacement.

In addition, the increase of the wireless communication data increases the power consumption, so the power maintenance of the sensor node is also a problem.

The present invention is to solve the above problems, the problem to be solved by the present invention is a database-based that can update the image of the sensor node by communicating only the delta information consisting of the difference between the current execution image of the sensor node and the image to be updated It provides a node update method and a target node operation method accordingly.

In order to solve the above problems, the node update method according to an aspect of the present invention, the step of extracting the execution image of the target node to be updated; And transmitting delta information on a difference between the execution image and the update image.

According to another aspect of the present invention, there is provided a method of operating a target node, the method comprising: determining whether an update is necessary when receiving an update request message; And receiving delta information on a difference between the current execution image and the update image and updating the delta information about the difference between the current execution image and the update image.

According to the present invention, since the execution image of the sensor node can be updated by transmitting only delta information using the difference between the execution image and the update image, the image can be updated even though the amount of wireless communication data is reduced compared to the conventional one. It also reduces the power consumption of sensor nodes.

In addition, in the present invention, since the delta information to be updated is smaller than the execution image, the sensor node can perform update by storing only the delta information in the memory, so that a large capacity memory is not required for the update.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating a sensor network for explaining a database-based node update method and a target node operation method according to an embodiment of the present invention.

Referring to FIG. 1, the sensor network may include a management server 100, a sink node 200, a target node 300, and a database 110.

The management server 100 is connected to the sink node 200 through the Internet, and may communicate with sensor nodes constituting the sensor network via the sink node 200.

The sink node 200 may configure a sensor network with the sensor nodes 300 and maintain a communication path with the management server 100.

The target node 300 is a target node that attempts to update a software image (hereinafter, referred to as an execution image) and is a sensor node constituting a sensor network.

Briefly explaining a node update method according to an embodiment of the present invention, the management server 100 can configure the delta information by using the difference between the execution image and the update image, and provides such delta information to the target node 300 As a result, the target node 300 may replace the execution image while reducing the amount of communication data.

Hereinafter, a method of updating a node of the management server 100 will be described in detail with reference to FIGS. 2 to 3.

The management server 100 may provide data to sensor nodes constituting the sensor network via the sink node 200. In addition, the management server 100 may further include a database 110 for holding information on the execution image of each sensor node currently running.

FIG. 2 is a schematic diagram showing stored data of a database. As shown in FIG. 2, the database 110 may include a node identifier for each node constituting a sensor network and an execution image of the sensor node currently running. Keep information about The delta information may be configured using the difference between the execution image and the update image stored in the database 110.

Accordingly, the management server 100 may know the current execution image of the target node 300 using the database 110, configure delta information on the difference between the current execution image and the update image, and target the configured delta information. By providing the node 300, an execution image of the target node 300 may be updated. Hereinafter, the node update method of the management server 100 will be described in detail.

3 is a flowchart illustrating a node update method according to an embodiment of the present invention.

The management server 100 generates a new update image to update the sensor node (S310), and selects a target target node 300 to perform the update (S320). Thereafter, the management server 100 may query the database 110 for the identifier of the target node 300 to extract information about the execution image currently executed by the target node 300 from the database 110. There is (S330).

In addition, the management server 100 may update the execution image information of the database 110 (S340). That is, since the target node 300 will update the update image with the new execution image, the management server 100 may update the database 110 by reflecting this. To this end, the management server 100 may perform the update by storing information on the update image in the execution image information of the target node 300 stored in the database 110. Through the update procedure of the database 110, the database 110 can maintain and manage the execution image information of each sensor node, it is possible to configure the delta information based on this.

In addition, the management server 100 may generate delta information by using a difference between the current execution image of the target node 300 and the new update image extracted from the database 110 as described above (S350). A method of generating such delta information will be described later with reference to FIG. 4.

The management server 100 may complete the update procedure of the target node 300 by transmitting the generated delta information to the target node 300 (S360). At this time, in order to transmit the delta information, the management server 100 transmits a message requesting the update (hereinafter referred to as an "update request message") to the target node 300, and a response message (hereinafter referred to as "update response") Message), the delta information may be transmitted to update the target node 300. In this case, the management server 100 waits for a predetermined time for the above-described update response message or response message for the delta information transmission, and if the response messages do not arrive, transmits the corresponding update request message or delta information again. It can be carried out.

Hereinafter, a method of generating delta information will be described with reference to FIG. 4.

4 is a configuration diagram illustrating a structure of an execution image of a target node.

As shown in FIG. 4, in accordance with an embodiment of the present invention, sensor nodes may execute an executable image of the depicted structure. Such an executable image may include fields for start code, byte count, address, data, and checksum, and the number of bytes shown is exemplary.

In this case, the address field of the execution image may indicate the address of the program memory of the sensor node. That is, the address field of a specific record of an execution image executed in the sensor node may correspond to the address of the program memory of the sensor node, and the data field of the record having the address field is stored in the corresponding program memory address of the sensor node. It can represent the data to be.

The management server 100 may configure the delta information by using the structure of the execution image. That is, the management server 100 may extract differences between the two images by comparing whether the data field is different from each other based on the address field with respect to the current execution image and the update image of the target node 300. If an address field having a different data field is found between the two images, the management server 100 may extract the corresponding record of the update image and include it in the delta information.

That is, the management server 100 may generate delta information including records of an update image having the same execution image and address field but different update images, and the target node 300 may generate delta information for each record of the received delta image. The execution image can be updated by storing data in an address of a corresponding memory based on an address field.

According to the exemplary embodiment of the present invention, the image being executed can be updated by only transmitting a record that is different from the currently executed image without transmitting all the images to be updated, and thus, the sensor node can update the image. The size can be efficiently reduced, thereby minimizing data traffic and minimizing sensor node power consumption.

In addition, by using the execution image according to the embodiment of the present invention, the management server 100 may not need a separate encoding / decoding operation to generate delta information.

An example of applying the structure of the execution image shown in FIG. 4 is an intel hex file. In this case, data of a data field may be represented as a hexadecimal number (hex).

Hereinafter, a method of operating a target node according to an embodiment of the present invention will be described with reference to FIG. 5.

5 is a flowchart illustrating a method of operating a target node according to an embodiment of the present invention.

When the first booting starts, the target node 300 reflects the received update image and checks whether it is an update mode or a general application mode to perform an update function (S510). That is, when power is applied, the target node 300 reads information stored in a nonvolatile memory (for example, Flash, EEPROM, etc.). The target node 300 determines whether the target node 300 is an update mode or a normal application mode to perform an update procedure. You can perform the operation.

If the determination result is a general application mode, the target node 300 is performing a general operation as a sensor node (S530), and the management server 100 updates the request message using the sensor network via the sink node 200. When transmitting, it can be received (S540).

The target node 300 receiving the update request message checks whether an update is necessary (S550). In this case, in order to check whether an update is necessary, the management server 100 may transmit the update request message including the version information of the update image to be updated, and the target node 300 that receives the update request message may transmit the same. It is possible to determine whether the update is necessary by extracting the version information of the update image from the update request message, and also extracting and comparing the version information of the execution image being executed.

If it is not necessary to update, general operation can be continued as an application mode.

On the other hand, if the update is necessary, the target node 300 may establish a communication channel with the management server 100 to receive the delta information for update as described above and perform the update (S560). That is, the target node 300 receives delta information transmitted from the management server 100, extracts an address field of each record constituting the received delta information, and corresponds to an address of a memory corresponding to the address field. The update can be performed by storing the data of the record. This is because, as described above, the execution image of the sensor node is configured in the structure shown in FIG. 4, therefore, the target node 300 may perform an update by storing the received delta information in a memory without requiring any decoding process. It can be.

At this time, the target node 300 may store the data of the delta information in the non-volatile memory, through which the data for the update image (that is, the data for the delta information) even when the target node 300 is rebooted in the update mode. May not be lost. In addition, when the reception of the delta information is completed, the target node 300 may store the related information in the nonvolatile memory so that the target node 300 can be rebooted in the update mode. After completing this process, the target node 300 performs a reset. (S570).

In response to the reset, the target node 300, which has been rebooted, may enter the update mode and perform an update procedure according to step S510 of determining whether to perform an update function (S520). Through this update procedure, the execution image can be updated with the update image using the delta information.

In addition, when such an update is completed, the version information of the update image can be recorded as the version information of the image currently being executed. This recording step may be performed after recording the data of the above-described delta information. In this case, the version information of the update image may use the information included in the above-described update request message, or may record the version information by using the information transmitted by being included in the delta information.

As mentioned above, although this invention was demonstrated in detail with reference to attached drawing, this is only an illustration, It is clear that various deformation | transformation and a change are possible within the scope of the technical idea of this invention. Therefore, the protection scope of the present invention should not be limited to the above-described embodiment, but should be determined to include the scope according to the description of the following claims and their equivalents.

1 is a block diagram illustrating a sensor network for explaining a database-based node update method and a target node operating method according to an embodiment of the present invention.

2 is a configuration diagram schematically showing stored data in a database.

3 is a flowchart illustrating a node update method according to an embodiment of the present invention.

4 is a configuration diagram illustrating a structure of an execution image of a target node.

5 is a flowchart illustrating a method of operating a target node according to an embodiment of the present invention.

Claims (10)

Extracting an execution image of a target node to be updated; And And transmitting delta information on the difference between the execution image and the update image. The method of claim 1, wherein the execution image and the update image of the target node, And at least one record including an address field containing a memory address of the target node. The method of claim 2, wherein the transmitting of the delta information comprises: Comparing the execution image with the data of the update image by referring to the address field; And generating the delta information, including the record of the update image, in which the data is not identical as a result of the comparison. The method of claim 1, wherein the extracting of the image comprises: Configuring a database for storing node identifiers for each node and the execution image; Extracting the execution image of the target node from the database using the identifier of the target node. The method of claim 4, wherein extracting the image comprises: After extracting the execution image, updating the database to store the update image as an execution image of the target node. The method of claim 1, wherein the transmitting step, Sending an update request message to the target node; And the update request message includes version information of the execution image. Determining whether an update is necessary when receiving an update request message; And And if the result of the determination needs to be updated, receiving delta information on the difference between the current execution image and the update image and storing the delta information in a memory of the target node. The method of claim 7, wherein the determining step, Extracting version information of the update image included in the received update request message; And extracting version information of an image currently being executed and comparing it with version information of the update image to determine whether the update is necessary. The method of claim 7, wherein And after recording the data of the delta information, recording the version information of the update image as version information of the currently executing image. The method of claim 7, wherein the storing step, Storing data of a corresponding record at an address of a memory corresponding to an address field of each record constituting the delta information; And And resetting the target node.

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