KR20170093475A - Apparatus and method for managing dynamic address allocation in wireless sensor network - Google Patents

Abstract

Provided is an apparatus for allocating and operating a dynamic address in a dynamic wireless sensor network environment with a long range property. The apparatus for allocating and operating a dynamic address includes: a mode selecting unit which selects and activates any one mode of an address allocation mode and an address request mode; and a processing unit which allocates an IP address to at least one AP among a plurality of access points included in a wireless sensor network if the activated mode is an address allocation mode and broadcasts an address request message for receiving the dynamic IP address if the activated mode is the address request mode. Accordingly, the present invention can allocate the dynamic IP address for flexibly dealing with a replacement situation or dynamic composition of a railway vehicle.

Description

TECHNICAL FIELD [0001] The present invention relates to a dynamic address allocation apparatus,

More particularly, the present invention relates to a wireless sensor network communication technology, and more particularly, to a wireless sensor network environment having a long range characteristic and dynamically configuring an IP address necessary for delivering sensing data to an end terminal through an IP relay To an apparatus and method for assigning the same.

Recently, there is a need for an intelligent on-board monitoring system using real-time sensing technology in order to secure the safety of a railway vehicle during a high-speed running and to improve the efficiency of the maintenance cost. In the case of a traveling device mounted on a railway vehicle, status information is collected using a wireless sensor device due to accessibility of the parts or the installation place, and then transmitted to a monitoring system through a railway-based wireless sensor network provided inside the railway vehicle do.

In this paper, we propose a wireless sensor network (WSN) and a wireless sensor network gateway (WSN) to transmit and receive sensing information. . The sensing information measured through the wireless sensor device is transmitted to the WSN AP of the corresponding carriage using the wireless communication method of IEEE 802.15.4 / ZigBee, and then the WSN AP of the neighboring carriage is sequentially installed on either side of the railroad car WSN GW.

Wi-Fi is mainly used for the wireless communication method between WSN AP and WSN GW, and IP address assignment work should be performed in this process. In a railway wireless sensor network environment, a common high-speed train for passengers can maintain a constant number of passengers so that static IP addresses can be assigned. However, if the number of passengers fluctuates frequently such as freight railroad cars, There are limitations in the following. Therefore, it is necessary to apply dynamic IP address assignment technology to more flexibly cope with dynamic organization and replacement situation of railway vehicles.

According to one aspect of the present invention, there is provided an apparatus for allocating and operating dynamic addresses in a dynamic wireless sensor network environment having long-distance characteristics. Wherein the dynamic address allocation operating apparatus comprises: a mode selection unit for selecting and activating one of an address allocation mode and an address requesting mode; and a plurality of APs included in the wireless sensor network if the active mode is the address allocation mode, And an Access Point), and broadcasts an address request message for allocating a dynamic IP address when the active mode is the address request mode.

According to one embodiment, when the active mode is the address allocation mode, the processing unit broadcasts an address assignment message from at least one AP included in the wireless sensor network, A dynamic IP address can be assigned by selecting a first AP located closest to the first AP.

At this time, the processing unit selects the first AP based on RSSI (Received Signal Strength Indication) information of each AP acquired using the address assignment message received from the at least one AP.

In addition, the processing unit may broadcast the dynamic IP address to the selected first AP.

According to an embodiment, when the allocation of the dynamic IP address to the first AP is completed, the processor may deactivate the address allocation mode and switch to the sensing data reception mode.

According to an embodiment, when the active mode is the address request mode, the processor may continuously broadcast the address request message until an address assignment message is received.

At this time, the processing unit sets and stores a dynamic IP address allocated based on the address assignment message received via broadcast.

In addition, the processing unit may switch to the address allocation mode when the setting of the dynamic IP address is completed.

According to another aspect, a method of allocating dynamic addresses in a dynamic wireless sensor network environment is provided. The method includes the steps of: activating an address assignment mode; receiving an address assignment message broadcast from at least one AP included in the wireless sensor network in response to the address assignment mode; Selecting a first AP in the selected location, and assigning a dynamic IP address to the selected first AP.

Here, the step of selecting the first AP may select the first AP based on RSSI (Received Signal Strength Indication) information of each AP acquired from the address assignment message received from the at least one AP.

Illustratively but not exclusively, the step of selecting the first AP selects the AP with the highest RSSI value as the first AP.

According to an exemplary embodiment, the step of allocating the dynamic IP address may broadcast the dynamic IP address to the selected first AP.

The method may further include, when the allocation of the dynamic IP address to the first AP is completed, deactivating the address allocation mode and switching to a sensing data reception mode.

According to another aspect, a method for requesting dynamic addresses in a dynamic wireless sensor network environment is provided. The method includes the steps of: activating an address request mode; broadcasting an address request message continuously until an address assignment message is received in response to the address request mode; And setting and storing a dynamic IP address.

Here, the address assignment message may be obtained in a broadcast manner.

The method may further include switching to an address allocation mode when the setting of the dynamic IP address is completed.

1 is a conceptual diagram illustrating a railroad wireless sensor network for a freight railway vehicle.
2 is a block diagram illustrating a dynamic address assignment operator in accordance with one embodiment.
3 is a block diagram of a detailed configuration of a dynamic address allocation node according to an embodiment.
4 is a block diagram of a detailed configuration of a dynamic address request node according to an embodiment.
5 is a diagram illustrating a processing process for dynamic address allocation operation according to an embodiment.
6 is a diagram illustrating a message structure for dynamic address allocation and dynamic address request according to an embodiment.
7 is a flowchart illustrating a dynamic address assignment method according to an embodiment.
8 is a flow diagram illustrating a dynamic address request method in accordance with one embodiment.

It is to be understood that the specific structural or functional descriptions of embodiments of the present invention disclosed herein are presented for the purpose of describing embodiments only in accordance with the concepts of the present invention, May be embodied in various forms and are not limited to the embodiments described herein.

Embodiments in accordance with the concepts of the present invention are capable of various modifications and may take various forms, so that the embodiments are illustrated in the drawings and described in detail herein. However, it is not intended to limit the embodiments according to the concepts of the present invention to the specific disclosure forms, but includes changes, equivalents, or alternatives falling within the spirit and scope of the present invention.

The terms first, second, or the like may be used to describe various elements, but the elements should not be limited by the terms. The terms may be named for the purpose of distinguishing one element from another, for example without departing from the scope of the right according to the concept of the present invention, the first element being referred to as the second element, Similarly, the second component may also be referred to as the first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Expressions that describe the relationship between components, for example, "between" and "immediately" or "directly adjacent to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises ", or" having ", and the like, are used to specify one or more of the features, numbers, steps, operations, elements, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning of the context in the relevant art and, unless explicitly defined herein, are to be interpreted as ideal or overly formal Do not.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these embodiments. Like reference symbols in the drawings denote like elements.

1 is a conceptual diagram illustrating a railroad wireless sensor network for a freight railway vehicle.

In order to secure the safety of railway vehicles at high speed, railway based wireless sensor network technology is needed which automatically senses the state of the railway vehicle critical devices and collects the measured data and transmits them in a wireless manner. For this purpose, a sensor device that senses the status of a railway vehicle in real time in a railway system environment, a WSN AP (Wireless Sensor Network Access Point) and WSN GW (Wireless Sensor Network Gateway) that transmit sensed data are composed of a railway wireless sensor network .

In FIG. 1, the wireless sensor device 111 transmits sensing information in real time to a wireless sensor network access point (WSN AP) 110 as an upper node. IEEE802.15.4 / ZigBee may be used for wireless communication between the wireless sensor device 111 and the WSN AP 110. [ The WSN AP 110 is an apparatus operated by each passenger vehicle of a railway vehicle and transmits sensing information received from at least one wireless sensor device 111 of the object to the other WSN GW 100 in the direction of the WSN GW 100 through IP communication. WSN AP. The wireless sensor network gateway (WSN GW) 100 collects, stores, and monitors sensing information received from at least one WSN AP of the railway vehicle on one side of the railway vehicle.

Since the WSN AP 110 and the WSN GW 100 mainly use Wi-Fi based IP communication, it is necessary to set an IP address for wireless communication between the WSN AP 110 and the WSN GW 100. There are two methods of IP address allocation: static allocation method and dynamic allocation method. In the case of a general high-speed train for passengers, the static address allocation method is possible because the number of carriages is kept constant. However, The dynamic address allocation scheme which can flexibly respond to the dynamic arrangement and replacement situation of the railway vehicle is more efficient than the static address allocation scheme.

Dynamic Dynamic Host Configuration Protocol (DHCP) is used in a typical dynamic address allocation scheme, which can set the WSN GW as a DHCP server and operate the WSN AP as a DHCP client. However, since the rail-based network environment has a long range characteristic, it is impossible to perform Wi-Fi communication with the WSN AP of the carriage which is far away from the WSN GW, so that the dynamic address allocation method of DHCP is applied to the railway network environment It is difficult to do.

2 is a block diagram illustrating a dynamic address assignment operator in accordance with one embodiment.

The dynamic address allocation management apparatus 200 is configured to provide a dynamic address so that the sensing information can be transmitted through Wi-Fi-based IP communication in an environment such as a freight train where a wireless sensor network can be dynamically configured with a long- And may include a mode selection unit 210 and a processing unit 220. [

The mode selection unit 210 can select one of the address allocation mode and the address request mode and activate the mode.

The processing unit 220 may perform a dynamic IP address allocation procedure or a dynamic IP address request procedure in response to the activated mode. If the activated mode is the address allocation mode, the processing unit 220 operates as a dynamic address allocation node, and assigns a dynamic IP address to at least one of a plurality of APs included in the wireless sensor network. If the activated mode is the address request mode, the processing unit 220 operates as a dynamic address requesting node and broadcasts an address request message for receiving a dynamic IP address.

First, when the processing unit 220 operates as a dynamic address allocation node, the processing unit 220 broadcasts an address assignment message from at least one AP included in the wireless sensor network, A dynamic IP address can be assigned by selecting a first AP located closest to the first AP. At this time, the processing unit 220 can select the first AP based on RSSI (Received Signal Strength Indication) information of each AP acquired together with the address allocation message received from the at least one AP. Generally, since the strength of the RSSI signal is inversely proportional to the distance, the AP with the strongest RSSI is selected as the first AP. The processing unit 220 performs an allocation procedure by broadcasting the dynamic IP address to the selected first AP. When the allocation of the dynamic IP address to the first AP is completed, the processing unit 220 may deactivate the address allocation mode and switch to the sensing data reception mode.

However, when the processing unit 220 operates as a dynamic address requesting node, the processing unit 220 continuously broadcasts the address request message until receiving the address assignment message. When the address assignment message is received, the processing unit 220 can set and store a dynamic IP address included in the address assignment message received in a broadcast manner. When the setting of the dynamic IP address is completed, the processing unit 220 may switch to the address allocation mode and perform an address allocation procedure for another AP.

3 is a block diagram of a detailed configuration of a dynamic address allocation node according to an embodiment.

3, the dynamic address assignment node includes a dynamic address assignment activation unit 310, a dynamic address request message reception unit 320, a WSN AP selection unit 330, an IP address assignment unit 340, (350) and a dynamic address allocation mode deactivation unit (360).

The dynamic address assignment mode activating unit 310 activates a function to allow an IP address to be assigned to another WSN AP in the wireless sensor network. The dynamic address request message receiving unit 320 receives a dynamic address assignment request message from at least one WSN AP in the wireless sensor network as a broadcast. The WSN AP selection unit 330 selects a WSN AP closest to its own location. Based on the RSSI (Received Signal Strength Indication) information of each AP acquired together with the dynamic address allocation request message, The AP can be determined as the closest WSN AP. The IP address assigning unit 340 assigns a dynamic IP address to the selected WSN AP and the allocated dynamic IP address is broadcasted to the selected WSN AP through the dynamic address assignment message transmitting unit 350. When the dynamic address allocation for the selected WSN AP is completed, the dynamic address allocation mode deactivation unit 360 may deactivate the dynamic address allocation mode and switch to the sensing data reception mode.

4 is a block diagram of a detailed configuration of a dynamic address request node according to an embodiment.

4, the dynamic address request node includes a dynamic address request mode activation unit 410, a dynamic address request message transmission unit 420, a dynamic address assignment message reception unit 430, a dynamic IP address setting unit 440, A storage unit 450 and a dynamic IP address allocation node configuration diagram 460.

The dynamic address request mode activation unit 410 activates a function for the WSN AP to receive a dynamic IP address from a WSN GW or another WSN AP in the wireless sensor network. The dynamic address request message transmitting unit 420 transmits a dynamic address request message to the broadcast to be allocated a dynamic IP address. In this process, the dynamic address request node continuously broadcasts the dynamic address request message until a dynamic IP address is assigned. The dynamic address assignment message receiving unit 430 broadcasts a dynamic address assignment message corresponding to the dynamic address request message. The dynamic IP address setting unit 440 sets and uses the assigned IP address based on the received dynamic address assignment message. The IP address storage unit 450 stores the set IP address as the IP address of the dynamic address assignment node, and the IP address is used as a destination address for transmitting data. The dynamic IP address assignment node configuration diagram 460 switches the mode to perform the function of the dynamic IP address assignment node after the dynamic address request node is assigned an IP address.

5 is a diagram illustrating a processing process for dynamic address allocation operation according to an embodiment.

The wireless sensor network gateway (WSN GW) 510 obtains information about the total number of WSN APs (numWSNAP) constituting the wireless sensor network (511). The information on the number of WSN APs (numWSNAP) is used to determine whether or not the number of WSN APs corresponds to the last WSN AP waiting for dynamic address allocation in the wireless sensor network.

5, WSN GW 510 is driven 511 to dynamic address allocation mode operation while WSN APs 520, 530 and 540 are driven 521, 531, and 541 in dynamic address request mode operation. . The wireless sensor network APs 520, 530 and 540 broadcast an IP allocation request message ("IP Allocation Request") including its own MAC address to be assigned a dynamic address.

The WSN GW 510 receives an IP allocation request message ("IP Allocation Request") from at least one WSN AP 520, 530, 540 included in the wireless sensor network during the WaitRcvMsg 512. At this time, the WSN GW 510 may acquire the RSSI signal strength information of the WSN APs 520, 530, and 540 that have transmitted the IP allocation request message. The WSN GW 510 determines that the WSN AP # 1 520 having the strongest RSSI signal is the AP closest to the RSSI signal intensity and the distance is inversely proportional to the RSSI signal strength and distance. After that, the numWSNAP value is decreased by one (513). The WSN GW 510 transmits an IP allocation response message including a MAC address of the WSN AP # 1, a dynamic IP address to be allocated, and a numWSNAP value to the selected WSN AP # 1 520 in response to the IP allocation request message. ("IP Allocation Response") as a broadcast. When the dynamic IP address allocation process for the WSN AP # 1 520 is completed, the WSN GW 510 switches the dynamic address allocation mode to the inactive state and the sensor data reception mode to the active state (514) .

When the WSN AP # 1 520 receives the IP allocation response message ("IP allocation response"), it sets the allocated IP address (522). Also, if the received numWSNAP value is not 0 (523), the WSN AP # 1 520 switches from the dynamic address request mode to the dynamic address assignment mode (524).

Meanwhile, the other WSN APs 530 and 540 that have not been assigned an IP continue to broadcast an IP allocation request message ("IP Allocation Request") including its MAC address until an IP is allocated. The WSN AP # 1 520 receives an IP allocation request message ("IP Allocation Request") from at least one other WSN AP during the WaitRcvMsg 525, and the RSSI signal of the received WSN APs After selecting the WSN AP # 2, the numWSNAP value is decreased by one (526). In response to the IP allocation request message, the WSN AP # 1 520 transmits an IP allocation response including a MAC address of the WSN AP # 2, a dynamic IP address to be allocated, and a numWSNAP value to the selected WSN AP # Message ("IP Allocation Response") is broadcast. When the dynamic IP address allocation procedure for the WSN AP # 2 530 is completed, the WSN AP # 1 520, like the WSN GW 510, switches the dynamic address allocation mode to the inactive state, Mode to an active state (527). When the last WSN AP # n 540 receives the IP allocation response message ("IP Allocation Response") in this manner, the assigned IP address is set (542). If the numWSNAP value is 0 (543), the last WSN AP #n 540 recognizes that it is the last WSN AP and switches directly to the sensor data reception mode activation state without switching to the address allocation mode (544).

FIG. 6A is a diagram illustrating a message structure defined for dynamic address allocation in a wireless sensor network environment having a long-distance characteristic according to an exemplary embodiment. FIG. 6A illustrates a dynamic address assignment request message ("IP Allocation Request & 6B represent dynamic address assignment response messages ("IP Allocation Response").

For dynamic address request and assignment, the dynamic address assignment request message of FIG. 6A and the dynamic address assignment response message of FIG. 6B are transmitted in a broadcast manner within the wireless sensor network.

6A, the source address of the Ethernet header included in the dynamic address allocation request message is the MAC address value 611 of the dynamic address request node, and the destination address is set to FF: FF: FF: FF: FF: FF 612 do. In addition, the source address of the IP header is 0.0.0.0 (613), and the destination address is set to 255.255.255.255 (614). The message identifier included in the payload of the dynamic address allocation request message indicates an IP ALLOCATION REQUEST 615 and the MAC address 616 of the dynamic address request node is set.

6B, the source address of the Ethernet header is the MAC address value 621 of the dynamic address allocation node, and the destination address is FF: FF: FF: FF: FF : FF (622). In the dynamic address assignment response message, the source address of the IP header is the IP address 623 of the dynamic address assignment node, and the destination address is set to 255.255.255.255 (624). In addition, the message identifier of the payload indicates "IP ALLOCATION RESPONSE" 625, the MAC address is set to the MAC address 626 of the dynamic address request node, do. A numWSNAP value 628 is added to the payload of the dynamic address assignment response message.

7 is a flowchart illustrating a dynamic address assignment method according to an embodiment.

Dynamic Address Allocation The operating device provides a dynamic address allocation method that enables the wireless sensor network to transmit sensing information through Wi-Fi based IP communication in an environment such as a freight train where the sensor network can be dynamically configured.

In step 710, the mode selection unit of the dynamic address allocation operating device may activate the dynamic address allocation mode.

In response to the dynamic address allocation mode, in step 720, the processing unit of the dynamic address allocation operating apparatus broadcasts an address allocation message from at least one AP included in the wireless sensor network, Lt; RTI ID = 0.0 > AP < / RTI > In step 720, the processor may select the first AP based on RSSI (Received Signal Strength Indication) information of each AP acquired together with the address allocation message received from the at least one AP. Generally, since the strength of the RSSI signal is inversely proportional to the distance, the AP with the strongest RSSI is selected as the first AP.

In step 730, the processing unit may assign a dynamic IP address to the first AP selected in step 720. In step 730, the processor performs an allocation procedure by broadcasting a dynamic address assignment response message including the dynamic IP address to the first AP. After step 730, when the allocation of the dynamic IP address to the first AP is completed, the processing unit may deactivate the address allocation mode and switch to the sensing data reception mode.

8 is a flow diagram illustrating a dynamic address request method in accordance with one embodiment.

Dynamic Address Allocation The operating device provides a method to request dynamic address to send sensing information through Wi-Fi based IP communication in the environment like cargo train where wireless sensor network can dynamically configure.

In step 810, the mode selection unit of the dynamic address assignment operator may activate the dynamic address request mode.

In response to the dynamic address request mode, in step 820, the processing unit of the dynamic address allocation operating apparatus can continuously broadcast an address request message until receiving an address assignment message.

If the address request message is received, the processing unit can set and store the dynamic IP address allocated based on the address assignment message received in the broadcast mode. When the setting of the dynamic IP address is completed, in step 840, the processing unit switches to the address allocation mode and can perform an address allocation procedure for another AP.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA) , A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (1)

An address assignment mode and an address request mode; And
Assigns an IP address to at least one of a plurality of access points (APs) included in the wireless sensor network if the active mode is the address allocation mode, and allocates a dynamic IP address when the active mode is the address request mode A processor for broadcasting an address request message for receiving
And a dynamic address assignment operator.

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