JP6658569B2 - Packet receiving device, packet transmitting device, packet communication device, packet receiving method, packet transmitting method, and communication program - Google Patents

Description

  The present invention relates to a packet receiving device, a packet transmitting device, a packet communication device, a packet receiving method, a packet transmitting method, and a communication program.

  An MPTCP (Multipath Transmission Control Protocol) is used which is an extension of TCP / IP (Transmission Control Protocol / Internet Protocol), which is generally used as a communication protocol for transmitting and receiving information via a network, to improve throughput. Techniques are known (see Non-Patent Document 1). In this technique, by establishing a connection through a plurality of paths, redundancy is improved, and fault tolerance performance and line speed performance are improved. Further, in this technique, it is not necessary to add special processing of application software by using the option field of the TCP header.

  Further, in order to reduce a load due to a variation in communication quality of each of a plurality of paths in a technique using MPTCP, a technique of distributing a packet to a suitable path among a plurality of paths in MPTCP has been proposed (for example, see Patent Reference 1).

JP 2015-050746 A

RFC 6824: TCP Extensions for Multiple Operation with Multiple Addresses

  However, MPTCP cannot adapt to data communication other than TCP, and therefore cannot improve the reliability of communication using another protocol such as UDP (User Datagram Protocol). Also, in MPTCP, since similar data cannot be transferred to a plurality of paths, there is a high possibility that communication will be interrupted at the timing of switching between wireless communication and the like. In addition, in the technology using MPTCP, since the option field of the TCP header is used, the communication device that transmits and receives the packet must use a communication device that can recognize the option field of the TCP header. That is, in order to exchange packets using MPTCP, it is necessary to change to a communication environment that enables communication using MPTCP. On the other hand, some communication devices connected to the network do not recognize the option field of the TCP header. A communication device that does not recognize the option field of the TCP header cannot use MPTCP in a network communication environment using TCP / IP, and communication may be interrupted. Therefore, there is room for improvement in providing a communication device capable of transmitting and receiving packets while suppressing communication interruption.

  The present invention has been made in view of the above facts, and has a simple configuration, compared with making a change in a communication environment, a packet receiving apparatus capable of transmitting and receiving packets while suppressing communication interruption, and a packet transmission apparatus. It is an object to provide a device, a packet communication device, a packet receiving method, a packet transmitting method, and a communication program.

In order to achieve the above object, a packet receiving apparatus of the present invention is a packet receiving apparatus installed in a mobile body, each of which is connected to an external and an access point of a wide area communication network by wireless communication, and information indicating each of them. A plurality of wireless communication units, wherein a plurality of wireless communication units are provided, and the plurality of wireless communication units are provided with a narrow-area communication network header including information indicating an internal transmission source and an internal transmission destination in the mobile object. A wide-area reception for receiving, via a wide-area communication network, a wide-area communication network packet to which a wide-area communication network header including information indicating one of the communication units is added and encapsulated; and parts, in the wide area reception unit, when receiving a packet for a wide area network, a memory for temporarily storing the contents of the packet for a wide area network, in the wide area reception unit, stored in the memory If for wide area network packets having the same content as a wide area network packet is received, the received wide area reception unit, and a packet for a wide area network with the same content as the packet for wide area network, which is stored in the memory When a wide-area communication network packet having a content different from the storage content of the memory is received by the wide-area reception section, the wide-area reception section deletes the wide-area communication network packet received by the wide-area reception section from the packet . A return unit for removing the header for the wide area communication network and returning to the packet for the narrow area communication, and the narrow area communication network packet returned by the return unit to the header for the narrow area communication network via the narrow area communication network. And a short-range transmission unit for transmitting to the included internal destination.

  According to the packet receiving device of the present invention, the wide area receiving unit is configured such that the wide area communication header is added to each of the plurality of narrow area communication network packets to which the narrow area communication header is added, and the packet is encapsulated. The plurality of wide area communication network packets are received via the wide area communication network. The recovery unit removes the added wide area communication network header from each of the received wide area communication network packets, and returns to the plurality of narrow area communication network packets. Each of the returned plurality of narrow-area communication network packets is transmitted by the narrow-area transmission unit to the internal destination included in the narrow-area communication network header via the narrow-area communication network. Therefore, it becomes possible to receive the narrow-area communication network packet via the wide-area communication network without any change.

  For each of the plurality of wide area network packets received by the wide area receiving unit, the packet receiving device may include an internal source included in the narrow area network header and an external source included in the wide area network header. It may include a recording control unit that controls the recording to be performed in the recording unit in response. As described above, since the packet receiving device includes the recording control unit, it is possible to record the internal transmission source and the external transmission source in association with the wide area communication network packet received from the wide area communication network.

  The packet receiving device, when a wide area network packet having the same content as the wide area network packet already received by the wide area receiving section is received, the wide area having the same content as the already received wide area network packet. The communication device may include a deletion unit that deletes the communication network packet. In this way, by deleting the wide area communication network packet having the same content as the already received wide area network packet, it is possible to suppress the overlapping distribution of the wide area network packet having the same content. Become.

  As the packet for the wide area network, a packet encapsulated based on a connectionless protocol can be used. By encapsulating based on a connectionless protocol, there is no need to use special protocols and special mechanisms.

Further, the packet transmission device of the present invention is a packet transmission device installed in a mobile object, wherein a narrow area communication network header including information indicating an internal transmission source and an internal transmission destination in the mobile object is added. A narrow-area receiving unit that receives the packet for the local-area communication network via the narrow-area communication network, a copying unit that replicates the packet for the local-area communication network received by the narrow-area receiving unit, An encapsulation unit that attaches a wide area network header including information indicating the wireless communication unit to each of the plurality of narrow area network packets and encapsulates each as a wide area network packet; A plurality of wireless communication units connected to an access point of a network, and information indicating each is set, and each of the wide area communication network packets encapsulated by the encapsulation unit is transmitted to the plurality of wireless communication units. Yo It includes a wide-area transmission unit for transmitting to an external destination included in the header for the wide area network via the wide area network, wherein the wide-area transmission unit acquires the information indicating the radio field intensity of the access point of the wide area network The radio field intensity information acquisition unit, the location information acquisition unit that acquires the location information of the mobile unit, and the location information of the mobile unit acquired by the location information acquisition unit, and the radio field intensity acquired by the radio field intensity information acquisition unit And a log analyzer for analyzing a candidate of an access point to be connected at the current position of the moving object based on the recorded log, and the log analyzer further comprises: If the access point signal strength exceeding a predetermined threshold value by the information acquiring unit is a plurality acquired, based on the variance of the moving track or field intensity of the mobile to determine the access point to be connected

  According to the packet transmitting apparatus of the present invention, each of the plurality of narrow-area communication network packets received by the narrow-area receiving unit, by the encapsulating unit, an external destination determined based on the content recorded in the recording unit. A header for the wide area communication network including the indicated information is added, and the packet is encapsulated as a packet for the wide area network. Each of the encapsulated packets for the wide area communication network is transmitted by the wide area transmission unit to the external destination via the wide area communication network. Therefore, it becomes possible to transmit the narrow-area communication network packet via the wide-area communication network so that it can be received without any change.

  In the packet transmitting device, the recording unit is a recording unit in which the internal source included in the header for the narrow area network and the external source included in the header for the wide area network are recorded in association with each other, The encapsulation unit can determine an external transmission source corresponding to the recorded internal transmission source as an external transmission destination based on the content recorded in the recording unit. As described above, by determining the external transmission destination from the content recorded in the recording unit, and recording the external transmission source, it is possible to easily execute a reply to the external transmission source.

  Further, the packet transmission device includes a duplicating unit that duplicates each of the plurality of narrow area communication network packets, and the encapsulating unit includes: It can be encapsulated by adding a header. As described above, by duplicating the narrow-area communication network packet, a plurality of wide-area communication network packets having the same contents as the narrow-area communication network packet can be transmitted, and multiplex transmission becomes possible.

  Furthermore, in the packet transmitting apparatus, the narrow area receiving section, the encapsulating section, and the wide area transmitting section are installed in a mobile body, and the wide area transmitting section is set with information indicating an external transmission source, and communicates by wireless communication. The wireless communication unit may include a wireless communication unit connected to an access point of the wide area communication network, and the encapsulation unit may determine an external transmission source based on contents set in the wireless communication unit. As described above, by installing the packet transmitting apparatus on the mobile unit and connecting to the access point of the wide area communication network by wireless communication, the packet for the wide area communication network can be transmitted from the mobile unit to various electronic devices installed on the wide area communication network side. Can be transmitted.

  In this case, the wide-area transmission unit includes a radio-field intensity information acquisition unit that acquires information indicating the radio field intensity of the access point of the wide-area communication network, When a plurality of points are acquired, an access point to be connected can be determined based on the radio field intensity of each of the plurality of access points. For example, when the communication quality becomes stable as the radio wave intensity of the access point increases, stable packet transmission becomes possible by determining the access point having the highest radio wave strength as the connection destination.

  Further, the wide-area transmission unit includes a position information acquisition unit that acquires position information of the moving object, position information of the moving object acquired by the position information acquisition unit, and a radio wave intensity acquired by the radio wave intensity information acquisition unit. And a log analyzing unit that analyzes a candidate of an access point to be connected at the current position of the moving object based on the recorded log, and a log that is analyzed by the log analyzing unit. The access point candidate may be determined as an access point to be connected. Since the radio wave intensity may change according to the movement of the moving body, by recording a log in which the position of the moving body and the radio wave intensity are associated, a preferable access point to be connected from the recorded log is determined. It will be possible to decide.

  Further, the packet transmission device copies the data in the copy unit according to the radio wave intensity at the position based on the position information of the moving object acquired by the position information acquisition unit based on the log recorded in the log analysis unit. A packet number control unit for controlling the number of packets to increase or decrease may be included. Since the number of packets to be copied is increased or decreased by the packet number control unit, the number of packets can be copied by the number corresponding to the radio wave condition according to the radio wave intensity, and unnecessary duplication and excessive duplication can be suppressed. Possible.

  In the packet transmitting apparatus, a packet encapsulated based on a connectionless protocol can be used as the packet for the wide area communication network.

A packet communication device according to the present invention is a packet communication device installed in a mobile body, and includes a plurality of external communication units that communicate external and wide area communication network packets, and an internal transmission source and an internal transmission destination in the mobile body. A wide area communication in which a wide area communication header including information indicating any of the plurality of external communication units is added to a narrow area communication network packet to which a narrow area communication network header including information is added, and encapsulated. A wide- area receiving unit for receiving a network packet via a wide-area communication network by any of the plurality of external communication units; a wide-area communication network packet having the same content as the wide-area communication network packet already received by the wide-area receiving unit If but received, the deletion unit for deleting the packet for the wide area network with the same content as the received packet for the wide area network already, the received wide area reception unit, and for already wide area network received Packets from different contents of the packet for the wide area network, remove the header for the wide area network, the return unit for returning for short range communication network packets, and a narrow-area packet communication network has been restored by the restoration unit A packet receiving unit having a narrow area transmitting unit for transmitting to an internal destination included in the narrow area communication network header via the narrow area communication network, and information indicating an internal source and an internal destination in the mobile unit. header for a narrowband communication network short range receiver unit for receiving via the narrow-area communication network packets for local area communication network granted replicates the narrow area packet communication network received by the narrow-range receiver comprising A wide-area communication including, in each of the plurality of narrow-area communication network packets copied by the copying unit, information indicating any of the plurality of external communication units determined based on the content recorded in the recording unit; each global communication by applying a header for the network Encapsulation unit for encapsulating a use packet, and each of the encapsulated packets for wide area network by the encapsulating unit, a header for the wide area network via the wide area network by the plurality of external communication unit A packet transmission unit including a wide-area transmission unit for transmitting to the included external destination.

  Also, in the packet communication device of the present invention, the packet receiving device, the packet transmitting device, and an internal source included in a header for a narrow area network and an external source included in a header for a wide area network correspond. And a recording unit on which the recording is performed.

The packet receiving method of the present invention includes a plurality of wireless communication units in which a computer installed in a mobile unit is connected to an external and an access point of a wide area communication network by wireless communication, and information indicating each is set, A wide area communication including information indicating any of the plurality of wireless communication units in a short area communication network packet to which a short area communication network header including information indicating an internal transmission source and an internal transmission destination in the mobile object is added. When a packet for a wide area communication network to which a network header is added and encapsulated is received via a wide area communication network by any of the plurality of wireless communication units, and the wide area communication network packet is received, when the temporarily stored in a memory the contents of the packet for the wide area network, for wide area network packets having the same content as the stored packets for the wide area network to the memory is received, the memory Remove the packet for the wide area network with the same content as the stored packets for wide area network, if for a wide area network packets different content and stored content of the memory has been received, the packet for the received wide area network , Removing the wide area network header and returning to the narrow area network packet, and transmitting the returned narrow area network packet via the narrow area network to the internal transmission included in the narrow area network header. Send first.

In the packet transmission method of the present invention, a computer installed in a mobile unit transmits a packet for a local area network to which a header for a local area network including information indicating an internal source and an internal destination in the mobile unit is added. Received via the narrow area network, duplicates the received narrow area network packet, and for each of a plurality of copied narrow area network packets, includes information indicating a wireless communication unit for a wide area network. A header is added and each is encapsulated as a packet for a wide area communication network, each is connected to an access point of a wide area communication network by wireless communication, and the encapsulated information is encapsulated by a plurality of wireless communication units in which information indicating each is set. each packet for the wide area network, when transmitting to an external destination included in the header for the wide area network via the wide area network by the plurality of wireless communication unit, the encapsulation When transmitting each of the wide area communication network packet, to obtain information indicating the radio field intensity of the access point of the wide area communication network, to obtain the position information of the mobile, the obtained position information of the mobile, Recording a log in correspondence with the obtained radio field intensity, and based on the recorded log, including analyzing a candidate of an access point to be connected at the current position of the moving object, of the access point to be connected When analyzing a candidate, when a plurality of access points having a radio field intensity exceeding a predetermined threshold value are acquired, an access point to be connected is determined based on the moving trajectory of the moving object or the dispersion of the radio field intensity .

  The communication program of the present invention causes a computer to function as the packet receiving device, the packet transmitting device, or the packet communication device.

  According to such a packet receiving method, a packet transmitting method, and a communication program, a packet for a narrow area communication network can be transmitted and received via a wide area communication network without any change.

  As described above, according to the present invention, compared to making a change in the communication environment, there is an effect that packets can be transmitted and received with a simple configuration while suppressing communication interruption.

FIG. 1 is a block diagram illustrating an example of a configuration of a wireless communication system according to a first embodiment. It is a block diagram showing an example of each composition of a mobile side router and a cloud side router concerning a 1st embodiment. It is an image figure showing an example of a packet format. It is an image figure showing an example of the 1st data table. It is an image figure showing an example of the 2nd data table. It is a block diagram which shows an example of a computer structure of a mobile side router. It is a block diagram showing an example of a computer composition of a cloud side router. 5 is a flowchart illustrating an example of processing of the mobile router by the computer according to the first embodiment. 5 is a flowchart illustrating an example of processing of a cloud-side router by a computer according to the first embodiment. It is a block diagram showing an example of each composition of a mobile side router installed in a mobile concerning a 2nd embodiment, and a cloud side router installed in a cloud side. It is a flow chart which shows an example of processing of a mobile side router by a computer concerning a 2nd embodiment. It is a flow chart which shows an example of processing of a cloud side router by a computer concerning a 2nd embodiment. It is a block diagram showing an example of each composition of a mobile side router installed in a mobile concerning a 3rd embodiment, and a cloud side router installed in a cloud side. It is a flow chart which shows an example of processing of a mobile side router by a computer concerning a 3rd embodiment. It is a block diagram showing an example of each composition of a mobile side router installed in the mobile concerning a 4th embodiment, and a cloud side router installed in the cloud side. It is a flow chart which shows an example of processing of a mobile side router by a computer concerning a 4th embodiment. It is a block diagram showing an example of each composition of a mobile side router installed in a mobile concerning a 5th embodiment, and a cloud side router installed in a cloud side. It is an image figure showing an example of the packet format concerning a 5th embodiment. It is a flow chart which shows an example of processing of a mobile side router by a computer concerning a 5th embodiment. It is a flow chart which shows an example of processing of a cloud side router by a computer concerning a 5th embodiment.

[First Embodiment]
Hereinafter, a first embodiment according to the present invention will be described with reference to the drawings.

  FIG. 1 illustrates an example of a configuration of a wireless communication system 10 that transmits and receives information by wireless communication between a plurality of electronic devices including an electronic device mounted on a moving object such as a vehicle according to the first embodiment.

  As shown in FIG. 1, the wireless communication system 10 includes an electronic device mounted on the mobile unit 20 and an electronic device installed on the cloud unit 30, and the electronic device on the mobile unit 20 side and the electronic device on the cloud unit 30 side Information is exchanged between electronic devices.

  The mobile unit 20 includes a vehicle-side computer (hereinafter, referred to as a VPC) 22 and a vehicle-side programmable router (hereinafter, referred to as a VPR) 26. The VPC 22 and the VPR 26 are a network (Vehicle-side Local Area Network; hereinafter, a mobile-side LAN) capable of mutually transmitting and receiving data and commands between devices mounted in the mobile 20 as a narrow-area communication network on the mobile 20 side. 24).

  The VPC 22 performs various controls in the mobile unit 20, and when exchanging information with an external device of the mobile unit 20, the VPC 22 exchanges information (packet) with the VPR 26 via the mobile side LAN 24. Note that an IP address (Internet Protocol Address), which is an identification number for identifying the VPC 22, is set in the VPC 22 in advance.

  The VPR 26 has a packet transmission / reception function, and includes a plurality of wireless LAN adapters for communicating with a wireless communication network 37 for a wide area communication network. FIG. 1 shows an example in which the wireless communication antennas 28 and 29 included in each of the two wireless LAN adapters are described and communication is performed with the wireless communication network 37 via each of the two wireless communication antennas 28 and 29. However, the number is not limited to two, but may be one, or three or more. The VPR 26 is an electronic device that functions as a so-called gateway provided on the mobile-side LAN 24 in order to transmit and receive a packet as a narrow-area communication network packet to and from the VPC 22. The VPR 26 has a function of converting a packet transmitted from the VPC 22 into an external packet as a wide-area communication network packet that can be processed by the wireless communication network 37, and transmits the external packet transmitted from the wireless communication network 37 to the VPC 22 (mobile LAN 24). ), And has a function of transmitting the packet which can be processed in (). Note that an IP address (Internet Protocol Address) is set in the VPR 26 in advance. An IP address (Internet Protocol Address) is set in advance for each wireless LAN adapter.

  The cloud unit 30 includes a wireless communication network 37, a cloud-side router (Server-side Programmable Router; hereinafter, referred to as SPR) 36, and a cloud-side computer (Server-side Computer; hereinafter, referred to as SPC) 32. The wireless communication network 37 is connected to the SPC 32 via the SPR 36. FIG. 1 schematically shows a case where the SPR 36 is connected to one SPC 32. In other words, the cloud 31 is a group of electronic devices such as servers called a cloud and communication devices that communicate with the electronic devices, and includes at least a plurality of SPCs 32. In FIG. These are representatively shown.

  The wireless communication network 37 includes access points (APs) 38 and 39 and is connected to the SPR 36. In FIG. 1, two access points (APs) 38 and 39 are shown as an example of a device for wireless communication, but the number of access points (APs) is not limited to two. The number may be one, or three or more. The wireless communication network 37 transmits and receives information to and from the mobile unit 20 (wireless communication antennas 28 and 29) via access points (APs) 38 and 39 by wireless communication.

  The SPR 36 has a packet transmission / reception function, and is connected to the SPC 32. The SPC 32 and the SPR 36 are a network (Server-side Local Area Network; hereinafter, referred to as a cloud-side LAN) capable of mutually exchanging data and commands between devices installed in the cloud 31 as a narrow-area communication network on the cloud unit 30 side. ) 34. An IP address (Internet Protocol Address) is set in each of the SPC 32 and the SPR 36 in advance.

  The SPR 36 is an electronic device that functions as a so-called gateway provided at the boundary between the wireless communication network 37 and the SPC 32 (cloud-side LAN 34) of the cloud 31. The SPR 36 has a function of converting a packet transmitted from the SPC 32 into an external packet that can be processed by the wireless communication network 37 and transmits the external packet transmitted from the wireless communication network 37 to a packet that can be processed by the SPC 32 (cloud-side LAN 34). (See below for details).

  The SPC 32 is a computer that performs various controls on the cloud 31 side, and exchanges information (packets) with the SPR 36 via the cloud side LAN 34 when exchanging information with the mobile unit 20.

  FIG. 2 is a block diagram showing an example of each configuration of the VPR 26 installed in the mobile unit 20 and the SPR 36 installed in the cloud unit 30. The VPR 26 installed in the mobile unit 20 includes a LAN communication unit 261, a packet duplication unit 262, an encapsulation unit 263, wireless communication units 267S and 267R, and an encapsulation removal unit 269 on the mobile unit 20 side.

(Packet transmission from mobile unit 20 to cloud unit 30)
・ VPR26
First, the function of the VPR 26 when transmitting a packet from the mobile unit 20 to the cloud unit 30 is mainly performed by using the LAN communication unit 261, the packet duplication unit 262, the encapsulation unit 263, and the wireless communication units 267S and 267R. explain.

  The LAN communication unit 261 of the mobile unit 20 includes a wireless communication unit 267S, 267R that functions as a wireless LAN adapter for communicating with the wireless LAN 37 and the wireless communication network 37 via the packet duplication unit 262 and the encapsulation unit 263. It is connected to the.

  When transmitting a packet from the mobile unit 20 to the cloud unit 30, the LAN communication unit 261 of the mobile unit 20 transmits a packet (Internal Network Packet: hereinafter) indicating information to be processed in the mobile unit 20 transmitted from the VPC 22. , An internal packet) from the mobile LAN 24 and transmit the packet to the packet duplication unit 262. The packet duplication unit 262 has a function of duplicating a predetermined number of packets transmitted from the LAN communication unit 261 and transmitting each duplicated packet to the encapsulation unit 263. The encapsulation unit 263 converts each of the packets duplicated by the packet duplication unit 262 into a packet (External Network Packet: hereinafter, referred to as an external packet) that can be processed by the wireless communication network 37 and transmits the packet to the wireless communication units 267S and 267R. It has the function to do. The wireless communication units 267S and 267R have a function of transmitting a plurality of external packets transmitted from the encapsulation unit 263 to the wireless communication network 37 by wireless communication. An IP address (Internet Protocol Address) is set in advance for each of the wireless communication units 267S and 267R.

  Here, the packet encapsulated by the encapsulation unit 263 will be described.

  FIG. 3 shows an example of a packet format of a packet to be encapsulated in the encapsulation unit 263. In the first embodiment, the packet is encapsulated based on a connectionless protocol. In the first embodiment, the encapsulation unit 263 uses TCP / IP (Transmission Control Protocol / Internet), which is a communication protocol generally used as an Internet Protocol Suite, as an example of a connectionless protocol. A case in which a UDP (User Datagram Protocol) based on the IP protocol is used will be described.

  As shown in FIG. 3, an internal packet transmitted from the VPC 22 received from the mobile side LAN 24 includes data (indicated as Payload in FIG. 3) processed via the mobile side LAN 24 and a header for a narrow area communication network. It contains the IP (Internet Protocol) field. In the IP field of the internal packet, the IP address of the VPC 22 is set as the source IP address (Src IP). The external packet to be encapsulated has a header as a wide area communication network header obtained by adding a time stamp (Timestamp: shown as TS in FIG. 3) to UDP / IP to the internal packet. Thus, the external packet is encapsulated in the encapsulation unit 263 with the header added to the internal packet.

  The IP field of the header of the encapsulated external packet contains the destination IP address (Dst IP) and the source IP address (Src IP). The IP address of the SPR 36 of the cloud unit 30 is set in the destination IP address (Dst IP) of this IP field, and the IP address of the wireless LAN adapter that transfers the external packet is set in the source IP address (Src IP). Is set. The UDP field includes a source port (Src Port) and a destination port (Dst Port). A predetermined port number (for example, 0xaaaa) for processing the encapsulated packet in the VPR 26 is set in the source port (Src Port) of the UDP field, and the encapsulated packet in the SPR 36 is set in the destination port (Dst Port). A predetermined port number (for example, 0xffff) to be processed is set. The setting of these IP addresses and ports is executed by the encapsulation unit 263. Here, it is assumed that the IP address of the SPR 36 on the cloud unit 30 side set as the transmission destination IP address (Dst IP) of the IP field is set in the encapsulation unit 263 in advance.

  Therefore, when an internal packet is transmitted from the VPC 22, the VPR 26 receives the internal packet at the LAN communication unit 261, duplicates the internal packet into a plurality of packets at the packet duplication unit 262, and timestamps the UDP / IP at the encapsulation unit 363. The header with the stamp TS is attached (encapsulated). Then, the encapsulated external packet is transmitted from each of the wireless LAN adapters to the SPR 36.

  In the above description, the LAN communication unit 261 of the VPR 26 shown in FIG. 2 is an example of a narrow area receiving unit. The packet duplication unit 262 is an example of a duplication unit. The encapsulation unit 263 is an example of a return unit. The wireless communication units 267S and 267R as wireless adapters are an example of a wide-area transmission unit.

・ SPR36
Next, the function of the SPR 36 when receiving an external packet transmitted from the mobile unit 20 will be mainly described.

  As shown in FIG. 2, the SPR 36 installed on the cloud unit 30 includes a LAN communication unit 361, a packet duplication unit 362, an encapsulation unit 363, a WAN communication unit 364, an IP update unit 366, and an encapsulation removal unit 369. Have. The WAN communication unit 364 of the SPR 36 is connected to the LAN communication unit 361 via the IP updating unit 366 and the encapsulation removing unit 369.

  The WAN communication unit 364 has a function of receiving an external packet transmitted from the wireless communication network 37 and transmitting the external packet to the IP update unit 366. The IP updating unit 366 has a function of transmitting an external packet transmitted from the wireless communication network 37 to the encapsulation removing unit 369. Further, the IP updating unit 366 includes a memory 366M, and has a function of extracting data such as a source IP address included in the external packet when transmitting the external packet and recording the data in the memory 366M as a data table. are doing. The encapsulation removing unit 369 removes the encapsulation of the external packet by removing the header from the external packet transmitted from the IP updating unit 366, and transmits the decapsulated packet to the LAN communication unit 361. have.

Here, a data table recorded by the IP updating unit 366 will be described.
When the destination IP address (Dst IP) in the external packet is the IP address of the SPR 36 and the destination port (Dst Port) is a predetermined port (for example, 0xffff), the received external packet is It determines that the packet is encapsulated by the VPR 26, and records the data of the mobile unit 20 included in the external packet. Here, as an example of the data on the mobile unit 20 side, one of the IP address (Src IP of Internal Network Packet) and the time stamp TS (Timestamp) of the VPC 22 and any one of the wireless communication units 267S and 267R as the wireless LAN slave unit. IP address (Src IP of External Packet).

  In the following description, the IP updating unit 366 determines whether the IP address (Src IP) and the time stamp TS (Timestamp) of the VPC 22 and the IP address of any one of the wireless communication units 267S and 267R (the external packet Src IP) will be described as an example in which two data tables, a first data table 42 and a second data table 44, are constructed as data tables and stored in the memory 366M.

  FIG. 4 shows an example of the first data table 42, and FIG. 5 shows an example of the second data table 44.

  As shown in FIG. 4, the first data table 42 uses the IP address of the VPC 22 (denoted as VPC IP in FIG. 4) as a key and the queue of the time stamp TS (denoted as Time Stamp in FIG. 4) as a value. It is a dictionary type data table (IP-TS dictionary). Also, as shown in FIG. 5, the second data table 44 uses the IP address of the VPC 22 as a key and stores the IP addresses of a plurality of wireless LAN adapters of the VPR 26 to which the VPC 22 is connected (in FIG. 5, Wifi Adapter 1 and Wifi Adapter 2 are denoted). ) Is a dictionary-type data table (IP-IP dictionary) with the value of).

  Therefore, when the packet received by the WAN communication unit 364 shown in FIG. 2 is an encapsulated external packet, the IP updating unit 366 extracts data such as a source IP address included in the external packet and performs data table extraction. And sends it to the encapsulation removing unit 369. The encapsulation removing unit 369 removes the encapsulation of the external packet from the external packet transmitted from the IP updating unit 366 by deleting the header, and transmits the packet to the LAN communication unit 361.

  In the above description, the WAN communication unit 364 of the SPR 36 shown in FIG. 2 is an example of a wide area receiving unit. The IP updating unit 366 is an example of a recording control unit, and the memory 366M, the first data table 42, and the second data table 44 are examples of a recording unit. The encapsulation removing unit 369 is an example of a return unit. The LAN communication unit 361 is an example of a narrow area transmission unit.

(Packet transmission from cloud unit 30 to mobile unit 20)
Next, a case where a packet is transmitted from the cloud unit 30 to the mobile unit 20 will be described.

・ SPR36
First, the function of the SPR 36 when transmitting an external packet to the mobile unit 20 will be mainly described.
The LAN communication unit 361 of the SPR 36 is connected to the cloud-side LAN 34 and connected to the WAN communication unit 364 via the packet duplication unit 362 and the encapsulation unit 363. Further, the encapsulation unit 363 is also connected to the IP update unit 366. The WAN communication unit 364 is connected to the wireless communication network 37.

  Like the LAN communication unit 261 of the VPR 26, the LAN communication unit 361 of the SPR 36 has a function of receiving a packet transmitted from the SPC 32, that is, the cloud 31, from the cloud-side LAN 34 and transmitting the packet to the packet duplication unit 362. The packet duplication unit 362 has a function of copying a predetermined number of packets transmitted from the LAN communication unit 361 and transmitting each duplicated packet to the encapsulation unit 363, similarly to the packet duplication unit 262 of the VPR 26. ing. Note that the packet duplication unit 362 is also connected to the IP update unit 366, and refers to the second data table 44 so that when there are a plurality of destinations, the packet is transmitted to each of the plurality of destinations. Can be duplicated.

  The encapsulation unit 363 has a function of, like the encapsulation unit 263 of the VPR 26, converting each of the packets copied by the packet duplication unit 362 into an external packet that can be processed by the wireless communication network 37 and transmitting the packet to the WAN communication unit 364. ing. Note that the encapsulation unit 363 of the SPR 36 performs encapsulation based on the data table recorded in the IP update unit 366. More specifically, a plurality of IP addresses of the wireless communication units 267S and 267R recorded in the second data table 44 (IP-IP dictionary) are set as the destination address (Dst IP) of the external packet to be encapsulated. The WAN communication unit 364 has a function of transmitting a plurality of external packets transmitted from the encapsulation unit 363 to the wireless communication network 37.

  Therefore, when the SPR 36 receives a packet from the cloud 31, the SPR 36 duplicates the packet in the packet duplication unit 362, and performs encapsulation in the encapsulation unit 363, respectively. As the destination address (Dst IP) of the external packet to be encapsulated, a plurality of IP addresses of the wireless communication units 267S and 267R recorded in the second data table 44 (IP-IP dictionary) are used. By doing so, since the external packet is transmitted to each of the wireless communication units 267S and 267R of the VPR 26, it is possible to realize wireless multiplexing when acquiring (downloading) the external packet.

  In the above description, the LAN communication unit 361 of the SPR 36 shown in FIG. 2 is an example of a narrow area receiving unit. The packet duplication unit 362 is an example of a duplication unit. The encapsulation unit 363 is an example of a return unit. The WAN communication unit 364 is an example of a wide area transmission unit.

・ VPR26
Next, the function of the VPR 26 when transmitting a packet from the cloud unit 30 to the mobile unit 20 will be described mainly using the LAN communication unit 261, the encapsulation removal unit 269, and the wireless communication units 267S and 267R.

  Each of the wireless communication units 267S and 267R of the VPR 26 is connected to the LAN communication unit 261 via the encapsulation removing unit 269.

  The encapsulation removing unit 269 of the VPR 26 removes the encapsulation for the external packet by removing the header from the external packet, and removes the encapsulated packet from the LAN communication unit 261 in the same manner as the encapsulation removing unit of the SPR 36. It has the function of sending to Also, the encapsulation removing unit 269 determines that the destination IP address (Dst IP) of the external packet is the IP address of the wireless communication unit 267S, 267R included in the VPR 26, and the destination port (Dst Port) is a predetermined port (for example, 0xaaaa), it has a function of determining that the packet is an encapsulated external packet.

  Therefore, in the encapsulation removing unit 269 of the VPR 26, the external packet received by the wireless communication unit 267S, 267R is transmitted to the destination IP address (Dst IP) of the wireless communication unit 267S, 267R included in the VPR 26, and transmitted. When the destination port (Dst Port) is a predetermined port (for example, 0xaaaa), by removing the header, the encapsulation is removed, and the decapsulated packet is transmitted to the VPC 22.

  In the above description, the wireless communication units 267S and 267R of the VPR 26 shown in FIG. 2 are an example of a wide area receiving unit. Further, the encapsulation removing unit 269 is an example of a return unit. The LAN communication unit 261 is an example of a narrow area transmission unit.

  In this way, a plurality of connections can be realized simultaneously by wireless communication. Therefore, by sequentially switching the access point (AP) at any one of the plurality of wireless communication units on the mobile unit 20 side, one wireless communication can always be established, so that communication interruption due to handover is avoided. Can be.

  Each of the VPR 26 installed in the mobile unit 20 and the SPR 36 installed in the cloud unit 30 included in the wireless communication system 10 according to the first embodiment converts each constituent element into an electronic device having each function described above. It may be constructed by hardware such as a circuit, or at least a part of each constituent element may be constructed by a computer to realize the function.

FIG. 6 shows an example of a configuration in which the VPR 26 is realized by a computer.
As shown in FIG. 6, the computer operating as the VPR 26 includes a computer main body 50 including a CPU (Central Processing Unit) 52, a RAM (Random Access Memory) 54, and a ROM (Read Only Memory) 56. I have. The ROM 56 includes a mobile-side communication control program 56P for realizing each of the functions described above. The computer main body 50 includes an input / output interface (I / O) 58, and the CPU 52, the RAM 54, the ROM 56, and the I / O 58 are connected via a bus 59 so that commands and data can be exchanged. The I / O 58 is connected to the wireless communication units 267S and 267R, the nonvolatile memory 57, and the mobile LAN 24.

  The computer main body 50 reads the mobile communication control program 56P from the ROM 56 and expands it in the RAM 54, and the mobile communication control program 56P expanded in the RAM 54 is executed by the CPU 52, as shown in FIGS. It operates as VPR26. The mobile communication control program 56P includes a process for realizing each function of the LAN communication unit 261, the packet duplication unit 262, the encapsulation unit 263, and the decapsulation unit 269 of the VPR 26 shown in FIG.

FIG. 7 shows an example of a configuration in which the SPR 36 is realized by a computer.
As shown in FIG. 7, the computer that operates as the SPR 36 includes a computer main body 60 including a CPU 62, a RAM 64, and a ROM 66. The ROM 66 includes a cloud-side communication control program 66P for implementing each of the functions described above. The computer main body 60 includes an input / output interface (I / O) 68, and the CPU 62, the RAM 64, the ROM 66, and the I / O 68 are connected via a bus 69 so that commands and data can be exchanged. The I / O 68 is connected to the WAN communication unit 364, the nonvolatile memory 67, and the cloud-side LAN.

  The computer main unit 60 reads the cloud-side communication control program 66P from the ROM 66 and expands it in the RAM 64, and the cloud-side communication control program 66P expanded in the RAM 64 is executed by the CPU 62, as shown in FIGS. It operates as SPR36. The cloud-side communication control program 66P is used to implement the functions of the LAN communication unit 361, packet duplication unit 362, encapsulation unit 363, IP update unit 366, and encapsulation removal unit 369 of the SPR 36 shown in FIG. Including processes.

  FIG. 8 shows an example of a processing flow in the VPR 26 realized by a computer.

  First, a process for transmitting a packet from the mobile unit 20 to the cloud unit 30 will be described.

In step S100, the computer main body 50 determines whether to transmit or receive a packet. Packet transmission / reception determination can be made based on, for example, whether an external packet has been received from the wireless communication unit 267S or 267R or an internal packet has been received from the mobile LAN 24. When the internal packet is received from the mobile LAN 24, it is determined that the packet is to be transmitted. On the other hand, when an external packet is received from the wireless communication unit 267S, 267R, it is determined that the packet is received. In the next step S110, it is determined whether or not the result of the determination in step S100 is transmission. In the case of transmission, an affirmative determination is made, and the process proceeds to step S112. On the other hand, in the case of reception, a negative determination is made in step S110, and the process proceeds to step S120.
In step S112, the internal packets received from the mobile LAN 24 are temporarily stored, and in the next step S114, the temporarily stored internal packets are copied by a predetermined number. In the next step S116, a header is added to each of the duplicated internal packets as external packets, and the packet is encapsulated. In the next step 118, the encapsulated external packets are output to the wireless communication units 267S and 267R. As a result, the external packet is transmitted from the wireless communication units 267S and 267R. Next, in step S130, it is determined whether an end instruction has been issued due to power shutdown or the like. If a negative determination is made, the process returns to step S100. If an affirmative determination is made in step S130, this processing routine ends.

  Note that the process of step S112 executed by the computer main body 50 corresponds to the function of the LAN communication unit 261 of the VPR 26. Further, the processing in step S114 corresponds to the function of the packet duplication unit 262 of the VPR 26. Further, the processing in step S116 corresponds to the function of the encapsulation unit 263 of the VPR 26. Furthermore, the processing in step S118 corresponds to an external packet output function output to the wireless communication units 267S and 267R of the VPR 26.

  The external packets transmitted from the wireless communication units 267S and 267R by the processing of the computer main body 50 are received by the SPR 36 via the wireless communication network 37.

  FIG. 9 shows an example of the flow of processing in the SPR 36 realized by a computer.

  In step S200, the computer main body 60 determines whether to transmit or receive a packet. Packet transmission / reception determination can be made based on, for example, whether an external packet has been received from the WAN communication unit 364 or an internal packet has been received from the cloud-side LAN 34. When an internal packet is received from the cloud-side LAN 34, it is determined that the packet is to be transmitted. On the other hand, when an external packet is received from the WAN communication unit 364, it is determined that the packet has been received. In the next step S210, it is determined whether or not the result of the determination in step S200 is transmission. In the case of transmission, an affirmative determination is made, and the process proceeds to step S212. On the other hand, in the case of reception, a negative determination is made in step S210, and the process proceeds to step S220.

Here, the case of the reception determination of receiving the external packet transmitted from the mobile side will be described.
In step S220, the external packet received by the WAN communication unit 364 is temporarily stored, and it is determined whether the external packet is an encapsulated packet. As described above, whether or not the external packet is an encapsulated packet is determined by determining that the destination IP (Dst IP) in the external packet is the IP address of the SPR 36 and the destination port (Dst Port) is a predetermined port (for example, , 0xffff), it can be determined that the packet is encapsulated by the VPR 26.

  If an affirmative determination is made in step S221, the process proceeds to step S222. In step S222, data such as the source IP address included in the external packet is extracted and the data tables (the first data table 42 and the second data table 44) are recorded. In the next step S226, a process of removing the header from the encapsulated external packet is executed. In the next step S228, the internal packet from which the encapsulation has been removed is output to the cloud-side LAN. On the other hand, if a negative determination is made in step S221, an internal packet is output in step S228 by a normal UDP process. Next, in step S230, it is determined whether or not an end instruction has been issued due to power shutdown or the like. If a negative determination is made, the process returns to step S200. If an affirmative determination is made in step S230, the present processing routine ends.

  Note that the process of step S222 executed by the computer main body 60 corresponds to the function of the IP update unit 366 of the SPR. Further, the process of step S226 corresponds to the function of the encapsulation removing unit 369 of the SPR. Further, the processing in step S228 corresponds to the function of the LAN communication unit 361 of the SPR.

  Next, a process when a packet is transmitted from the cloud unit 30 to the mobile unit 20 will be described.

  As shown in FIG. 9, when transmitting a packet from the cloud unit 30 to the mobile unit 20, the computer main unit 60 operating as the SPR 36 makes an affirmative determination in step S210, and shifts the processing to step S212.

  In step S212, the internal packets received from the cloud-side LAN 34 are temporarily stored, and in the next step S214, a predetermined number of the temporarily stored internal packets are copied. In the next step S216, a header is added to each of the copied plurality of internal packets as external packets, and the packets are encapsulated. The external packet to be encapsulated is encapsulated based on a data table recorded in advance. That is, as described above, a plurality of IP addresses of the wireless communication units 267S and 267R recorded in the second data table 44 (IP-IP dictionary) are set as the transmission destination address (Dst IP) of the external packet to be encapsulated. Is done. In the next step 218, the encapsulated external packets are output to the WAN communication unit 364. As a result, the external packet is transmitted from the WAN communication unit 364.

  Note that the processing in step S212 executed by the computer main body 50 corresponds to the function of the LAN communication unit 361 of the SPR. The processing in step S214 corresponds to the function of the packet duplication unit 362 of the SPR 36. Further, the processing in step S216 corresponds to the function of the encapsulation unit 363 of the SPR. Furthermore, the process of step S218 corresponds to the external packet output function output to the WAN communication unit 364 of the SPR.

  The external packet transmitted from the WAN communication unit 364 by the processing of the computer main body 60 is received by the VPR 26 via the wireless communication network 37.

  As shown in FIG. 8, when a packet is transmitted from the cloud unit 30 to the mobile unit 20, the computer main body 50 operating as the VPR 26 makes a negative determination in step S110 and shifts the processing to step S120.

  In step S120, the external packet received by the wireless communication units 267S and 267R is temporarily stored, and it is determined whether the external packet is an encapsulated packet. As described above, it is determined whether or not the external packet is an encapsulated packet by determining that the destination IP (Dst IP) in the external packet is the IP address of the wireless communication unit 267S, 267R and the destination port (Dst Port) Is a predetermined port (for example, 0xffff), it can be determined that the packet is encapsulated by the SPR 36.

  If an affirmative determination is made in step S122, the process proceeds to step S126. In step S126, a process of removing the header from the encapsulated external packet is performed. In step S128, the internal packet from which the encapsulation has been removed is output to the mobile LAN 24. On the other hand, if a negative determination is made in step S122, an internal packet is output in step S128 by normal UDP processing.

  Note that the processing of step S126 executed by the computer main body 50 corresponds to the function of the encapsulation removing unit 269 of the VPR 26. Further, the process of step S128 corresponds to the function of the LAN communication unit 261 of the VPR 26.

  As described above, according to the wireless communication system of the first embodiment, data is exchanged between the mobile unit 20 and the cloud unit 30 by an external packet encapsulated based on a connectionless protocol, specifically, encapsulated by UDP. Therefore, packets can be transmitted and received without making special changes to the network of the mobile unit 20 and the network of the cloud unit 30. In the first embodiment, since a plurality of duplicated packets are used, wireless multiplexing can be realized.

[Second embodiment]
Next, a second embodiment will be described. In the first embodiment, a plurality of duplicated packets may be output to the mobile LAN 24 or the cloud LAN 34 to make the packets redundant. Thus, in the second embodiment, the packet is prevented from becoming redundant. Since the second embodiment has substantially the same configuration as that of the first embodiment, the same portions are denoted by the same reference numerals, detailed description thereof will be omitted, and differences will be described below.

  FIG. 10 illustrates an example of each configuration of the VPR 26 installed in the mobile unit 20 and the SPR 36 installed in the cloud unit 30 according to the second embodiment. The VPR 26 shown in FIG. 10 has a duplicate packet removing unit 268 provided between the wireless communication units 267S and 267R and the encapsulation removing unit 269 in the VPR 26 shown in FIG. Also, the SPR 36 shown in FIG. 10 has a duplicate packet removing unit 368 provided between the IP updating unit 366 and the encapsulation removing unit 369 in the SPR 36 shown in FIG.

  As shown in FIG. 10, the VPR 26 installed in the mobile unit 20 includes a duplicate packet removing unit 268. The duplicate packet removing unit 268 of the VPR 26 includes a memory 268M for temporarily storing the received external packet. The duplicate packet removing unit 268 has a function of deleting an external packet having the same content as an already received external packet. More specifically, the duplicate packet removing unit 268 temporarily stores the source IP address, the destination IP address, and the time stamp TS included in the external packet in the memory 268M, and stores the content of the stored external packet (for example, , Source IP address, destination IP address and time stamp TS) and the content of the received external packet. Then, when an external packet having the same content as that of the received external packet is stored in the memory 268M, the duplicate packet removing unit 268 deletes the received external packet. Thereby, it is possible to suppress the packet from becoming redundant on the mobile unit 20 side. Note that a checksum may be added to the source IP address, the destination IP address, and the time stamp TS.

  The SPR 36 installed in the cloud unit 30 also includes the duplicate packet removing unit 368. The duplicate packet removing unit 368 has a function of deleting the same external packet as the already received external packet when a plurality of packets are received, like the duplicate packet removing unit 268. Specifically, the duplicate packet removing unit 368 refers to the first data table 42 and the second data table 44, and transmits the same external packet as the recorded source IP address, destination IP address, and time stamp TS to the WAN communication. When the packet is received and input by the unit 364, the same external packet is deleted. Thereby, it is possible to suppress the packet from becoming redundant on the cloud unit 30 side. Note that a checksum may be added to the source IP address, the destination IP address, and the time stamp TS.

  In the above description, the duplicate packet removing unit 368 of the SPR 36 and the duplicate packet removing unit 268 of the VPR 26 shown in FIG. 10 are examples of a deleting unit.

  FIG. 11 illustrates an example of a processing flow when the VPR 26 according to the second embodiment is implemented by a computer. The processing flow shown in FIG. 11 is a case where the affirmative determination is made in step S122 in the processing flow shown in FIG. 8, and before the encapsulation removal processing is executed in step S126, the duplicate packet removal processing shown in step S124. Is added.

  Note that the process of step S124 executed by the computer main body 50 corresponds to the function of the duplicate packet removing unit 268 of the VPR 26.

  FIG. 12 illustrates an example of a processing flow when the SPR 36 according to the second embodiment is implemented by a computer. The processing flow illustrated in FIG. 12 is obtained by adding the duplicate packet removal processing illustrated in step S224 between steps S222 and S226 in the processing flow illustrated in FIG.

  Note that the process of step S224 executed by the computer main body 60 corresponds to the function of the duplicate packet removing unit 368 of the SPR.

  Therefore, when a plurality of the same external packets are transmitted from the mobile unit 20 to the cloud unit 30, if the IP address of the VPC 22 and the time stamp TS of the transmitted external packets are already recorded in the first data table 42, the VPR 26 It is determined that the duplicated external packet has been transmitted in duplicate, and the external packet is deleted. Similarly, when a plurality of the same external packets are transmitted from the cloud unit 30 to the mobile unit 20, the same external packets are deleted.

  As described above, according to the wireless communication system of the second embodiment, when a plurality of external packets are transmitted, the same external packet as the already received external packet is deleted, thus realizing wireless multiplexing. However, at least one of the mobile unit 20 side and the cloud unit 30 side can suppress a packet from becoming redundant.

[Third embodiment]
Next, a third embodiment will be described. In the third embodiment, each of the wireless communication units 267S and 267R (wireless adapter) in the VPR 26 on the mobile unit 20 side when the radio wave intensity of the access points (AP) 38 and 39 in the wireless communication network 37 is equal to or higher than a predetermined intensity Determines the optimal access point. The third embodiment has substantially the same configuration as the second embodiment. Therefore, the same portions are denoted by the same reference numerals, detailed description thereof will be omitted, and only the differences will be described below.

  FIG. 13 illustrates an example of each configuration of the VPR 26 installed in the mobile unit 20 and the SPR 36 installed in the cloud unit 30 according to the third embodiment. The VPR 26 shown in FIG. 13 is provided with a radio wave intensity acquisition unit 266A connected to each of the wireless communication units 267S and 267R in the VPR 26 shown in FIG. The SPR 36 shown in FIG. 13 is the same as the SPR 36 shown in FIG.

  As shown in FIG. 13, the VPR 26 installed on the mobile unit 20 includes a radio wave intensity acquisition unit 266A. The radio wave intensity acquisition unit 266A has a function of detecting and acquiring the radio wave intensity of the access points (AP) 38, 39 in the wireless communication network 37 from each of the wireless communication units 267S, 267R. Further, the radio wave intensity acquisition unit 266A has a function of determining, for example, an access point to which an access point having the highest radio wave intensity is to be connected, based on the acquired radio wave intensity. Each of the wireless communication units 267S and 267R has a function of connecting to the determined access point. As a result, the mobile unit 20 can connect to an optimal access point in the wireless communication network 37.

  FIG. 14 illustrates an example of a processing flow when the VPR 26 according to the third embodiment is implemented by a computer. In the processing flow illustrated in FIG. 14, before the transmission / reception determination processing is performed in step S100 in the processing flow illustrated in FIG. 11, the radio wave intensity acquisition processing illustrated in step S92 and the connection destination determination processing illustrated in step S94 are added. It was done.

  As shown in FIG. 14, when transmitting a packet from the mobile unit 20 to the cloud unit 30 side, in the computer main body 50, before executing the packet transmission / reception determination in step S100, the radio wave intensity of the access point is determined in step S92. To get. Next, in step S94, based on the acquired radio wave intensity, for example, an access point to which an access point having the highest radio wave intensity is connected is determined. In each of the wireless communication units 267S and 267R, connection to the access point determined in step S94 is performed.

  Note that the processing of steps S92 and S94 executed by the computer main body 50 corresponds to the function of the radio wave intensity acquisition unit 266A of the VPR 26.

  As described above, according to the wireless communication system of the third embodiment, even when there are a plurality of connectable access points (when the radio wave intensity is equal to or higher than the predetermined intensity), the optimum radio wave intensity of the access point is determined. An access point can be determined.

[Fourth embodiment]
Next, a fourth embodiment will be described.
If multiple access points with almost the same signal strength are detected, it is possible to connect to any of the access points, but the signal strength varies relatively among the multiple access points with almost the same signal strength. In this case, the connection is frequently switched between a plurality of access points. Therefore, in the fourth embodiment, an optimal access point to be connected is determined using the position history (log) of the moving object and the radio wave intensity of the access point. The fourth embodiment has substantially the same configuration as the third embodiment. Therefore, the same portions are denoted by the same reference numerals, detailed description thereof will be omitted, and differences will be described below.

  FIG. 15 illustrates an example of each configuration of the VPR 26 installed in the moving object 20 and the SPR 36 installed in the cloud unit 30 according to the fourth embodiment. The VPR 26 shown in FIG. 15 includes a log analysis unit 265 and a position information acquisition unit 266B in addition to the radio wave intensity acquisition unit 266A in the VPR 26 shown in FIG. Note that the SPR 36 shown in FIG. 15 is the same as the SPR 36 shown in FIG.

  As shown in FIG. 15, the radio wave intensity acquisition unit 266A and the position information acquisition unit 266B are connected to the log analysis unit 265. The log analysis unit 265 is connected to each of the wireless communication units 267S and 267R. The radio wave intensity acquisition unit 266A has a function of detecting and acquiring the radio wave intensity of the access points (AP) 38, 39 in the wireless communication network 37 from each of the wireless communication units 267S, 267R, as in the third embodiment. ing. The position information acquisition unit 266B has a function of detecting the current position of the moving body 20 and acquiring information indicating the current position. The log analysis unit 265 has a function of associating the current position of the mobile unit 20 acquired by the position information acquisition unit 266B with the radio wave intensity of the access point acquired by the radio wave intensity acquisition unit 266A and recording it as a position history (log). Have. Further, the log analysis unit 265 has a function of performing an analysis process for determining an optimal access point for connection using the recorded position history (log).

  As an example of the analysis processing in the log analysis unit 265, there is an analysis processing of determining an optimal access point from a movement trajectory of the moving body 20. More specifically, for example, when a plurality of access points are substantially equidistant from the moving object, information indicating the moving track of the moving object 20 is generated from the position history (log), and the access point to which the moving object 20 is approaching is determined. Determine as the optimal access point. By doing so, it is possible to avoid connection to an access point that is likely to be disconnected.

  Another example of the analysis process in the log analysis unit 265 is an analysis process of determining an optimum access point from the dispersion of radio wave intensity. More specifically, for example, when a plurality of access points are approximately equidistant from the mobile unit 20 and the mobile unit 20 is moving while approaching the plurality of access points, the radio wave intensity included in the position history (log) is determined. The variance is derived, and an access point having a small variance is determined as an access point having a stable radio field intensity. By doing so, it is also possible to avoid connection to an access point where disconnection is likely to occur.

  FIG. 16 illustrates an example of a processing flow when the VPR 26 according to the fourth embodiment is implemented by a computer. The processing flow illustrated in FIG. 16 is different from the processing flow illustrated in FIG. 14 in that the position information acquisition processing of the mobile unit 20 illustrated in step S90 is added before the radio wave intensity acquisition processing is performed in step S92 in FIG. In place of the connection destination determination processing in step S94 shown in the figure, processing for determining an optimal access point based on the position history (log) shown in step S95 is executed.

  As shown in FIG. 16, when transmitting a packet from the mobile unit 20 to the cloud unit 30 side, the computer main body 50 acquires and records the position information of the mobile unit 20 in step S90, and accesses in the next step S92. The radio wave intensity of the point is acquired and recorded. Next, in the analysis processing in step S95, for example, an access point to which the access point having the highest radio field intensity is connected is determined based on the acquired position information of the mobile unit 20 and the radio field intensity of the access point. In each of the wireless communication units 267S and 267R, connection to the access point determined in step S94 is performed.

  Note that the process of step S90 executed by the computer main body 50 corresponds to the function of the position information acquisition unit 266B of the VPR 26. The processing in step S92 corresponds to the function of the radio wave intensity acquisition unit 266A of the VPR 26. Further, the processing in step S95 corresponds to the function of the log analysis unit 265 of the VPR 26.

  As described above, according to the wireless communication system of the fourth embodiment, even when there are a plurality of connectable access points (when the radio field intensity is equal to or higher than the predetermined intensity), the position of the mobile unit 20 and the access points The optimum access point can be determined using the log in which the correspondence of the radio wave intensity is recorded.

[Fifth Embodiment]
Next, a fifth embodiment will be described.
The connection to the wireless communication network 37 is stabilized or unstable depending on the radio wave condition according to the strength of the radio wave intensity by the access point in the wireless communication network 37. In addition, when wireless multiplexing is performed using a plurality of external packets, if the number of overlapping external packets is too small, the connection is disconnected, and if the number is too large, redundant and extra packets are transmitted and received. Therefore, in the fifth embodiment, the number of external packets to be duplicated is increased or decreased according to the radio wave condition of the wireless communication network 37. Note that the fifth embodiment has substantially the same configuration as the fourth embodiment, and therefore, the same portions are denoted by the same reference numerals, detailed description thereof will be omitted, and differences will be described below.

  FIG. 17 illustrates an example of each configuration of the VPR 26 installed in the moving object 20 and the SPR 36 installed in the cloud unit 30 according to the fifth embodiment. The VPR 26 shown in FIG. 17 is provided with a packet number control unit 264 connected to the packet duplication unit 262, the encapsulation unit 263, and the log analysis unit 265 in the VPR 26 shown in FIG.

  The log analysis unit 265 of the fifth embodiment has a function of analyzing radio wave stability at each point by using a log indicating the recorded radio wave intensity of the access point associated with the position of the mobile unit 20. . The number-of-packets control unit 264 decreases according to the stability of the radio wave at each point analyzed by the log analysis unit 265 as the stability of the radio wave increases, and increases as the stability of the radio wave decreases. Has the function of determining the packet duplication number. The packet number control unit 264 has a function of controlling the packet duplication unit 262 and the encapsulation unit 263 so that the determined packet duplication number is transmitted to the cloud unit 30. That is, the packet number control unit 264 outputs an instruction command of the packet duplication number to the packet duplication unit 262 and the encapsulation unit 263, and reduces the packet duplication number when the radio wave condition in the wireless communication network 37 is stable. In the case of instability, the packet duplication number is increased.

  Further, the encapsulation unit 263 of the fifth embodiment has a function of encapsulating data including data indicating a packet overlap number.

FIG. 18 shows an example of a packet format of a packet to be encapsulated in the encapsulation unit 263 of the fifth embodiment.
I do.

  As shown in FIG. 18, the packet format 41 of the packet encapsulated by the encapsulation unit 263 of the fifth embodiment is the same as the packet format 40 shown in FIG. Dup) is added. That is, the external packet encapsulated by the encapsulation unit 263 of the fifth embodiment has a header in which a time stamp TS and data (Dup) indicating the packet duplication number are added to the internal packet.

  Also, the SPR 36 shown in FIG. 17 includes an IP update packet number control unit 367 instead of the IP update unit 366 in the SPR 36 shown in FIG.

  When receiving the external packet, the IP update packet number control unit 367 has a function of referring to the field (Dup) of the external packet and acquiring the packet duplication number. Further, the IP update packet number control unit 367 has a function of outputting the acquired packet duplication number to the packet duplication unit 362 and the encapsulation unit 363. Thereby, the packet duplication unit 362 and the encapsulation unit 363 can increase or decrease the packet duplication number.

  In the above description, the packet number control unit 264 of the VPR 26 shown in FIG. 17 is an example of a packet number control unit, and the IP update packet number control unit 367 of the SPR 36 is an example of a recording control unit and a packet number control unit. .

  FIG. 19 illustrates an example of a processing flow when the VPR 26 according to the fifth embodiment is implemented by a computer. The process flow illustrated in FIG. 19 is such that the internal packet is duplicated based on the recorded log shown in step S115 instead of the internal packet duplication process performed in step S114 in the process flow illustrated in FIG. The processing is executed.

  Note that the process of step S115 executed by the computer main body 50 corresponds to the function of the packet number control unit 264 of the VPR 26.

  FIG. 20 illustrates an example of a processing flow when the SPR 36 according to the fifth embodiment is implemented by a computer. The processing flow shown in FIG. 20 is different from the processing flow shown in FIG. 12 in that the processing of step S214 is replaced with the processing of duplicating an internal packet based on the packet duplication shown in step S215. is there. Also, in the processing flow shown in FIG. 20, instead of the processing in step S224 in the processing flow shown in FIG. 12, the processing of recording the packet duplication in the processing of removing duplicate packets shown in step S225 is executed. It is like that.

  Note that the processing of steps S215 and S225 executed by the computer main body 60 corresponds to the function of the IP update packet number control unit 367 of the SPR.

  As described above, according to the wireless communication system of the fifth embodiment, the number of packets is optimally changed on the mobile unit 20 side, and the packet number on the cloud unit 30 side is changed based on the change in the packet number on the mobile unit 20 side. Is also adjusted. Thereby, by suppressing unnecessary communication and overlapping packets with a necessary and sufficient number of packets, communication efficiency and reliability can be improved.

  Although the present invention has been described using the embodiment, the technical scope of the present invention is not limited to the scope described in the above embodiment. Various changes or improvements can be made to the above-described embodiment without departing from the spirit of the invention, and embodiments with such changes or improvements are also included in the technical scope of the present invention.

10 wireless communication system 20 mobile unit 22 mobile unit side computer (VPC)
24 Mobile side LAN
26 Mobile Router (VPR)
28, 29 Wireless communication antenna 30 Cloud unit 31 Cloud 32 Cloud-side computer (SPC)
34 Cloud side LAN
36 Cloud Side Router (SPR)
37 wireless communication network 38, 39 access point (AP)

Claims (9)

A packet receiving device installed in a mobile body,
Each of the mobile units includes a plurality of wireless communication units connected to the outside and the access point of the wide area communication network by wireless communication, and information indicating each of the wireless communication units is set. A wide area communication packet encapsulated with a wide area communication header including information indicating any of the plurality of wireless communication units is added to the short area communication network packet to which the wide area network header is added. A wide area receiving unit for receiving via any one of the plurality of wireless communication units via a wide area communication network,
A memory for temporarily storing the contents of the wide area communication network packet when the wide area communication network receives the wide area communication network packet; and a wide area communication network for storing the contents of the wide area communication network packet stored in the memory . When a wide area communication network packet having the same content as the packet is received, a deletion for deleting the wide area communication network packet having the same content as the wide area communication network packet received by the wide area receiving unit and stored in the memory. Department and
When the wide area receiving unit receives a wide area communication network packet having a content different from that stored in the memory, the wide area communication network header is removed from the wide area communication network packet received by the wide area receiving unit. And a return unit for returning to the narrow area communication network packet,
A short-range transmission unit that transmits the narrow-area communication network packet restored by the restoration unit to an internal destination included in the narrow-area communication network header via the narrow-area communication network,
A packet receiving device comprising: The packet receiving device according to claim 1, wherein the wide area communication network packet is a packet encapsulated based on a connectionless protocol. A packet transmission device installed in a mobile object,
A short-range communication unit that receives a short-range communication network packet to which a short-range communication network header including information indicating an internal transmission source and an internal transmission destination in the mobile object has been added, via a short-range communication network;
A copying unit that copies the narrow-area communication network packet received by the narrow-area receiving unit,
An encapsulating unit that adds a wide area communication network header including information indicating the wireless communication unit to each of the plurality of narrow area communication network packets duplicated by the duplication unit, and encapsulates each as a wide area communication network packet. ,
Each connected to an access point of a wide area communication network by wireless communication, and includes a plurality of wireless communication units in which information indicating each is set, each of the wide area communication network packets encapsulated in the encapsulation unit, A wide-area transmission unit that transmits to an external destination included in the wide-area communication network header via a wide-area communication network by a plurality of wireless communication units;
With
The wide area transmission unit is obtained by a radio field intensity information acquisition unit that acquires information indicating the radio field intensity of an access point of the wide area communication network, a position information acquisition unit that acquires position information of a mobile object, and the position information acquisition unit. A log that correlates the position information of the moving object and the radio wave intensity acquired by the radio wave intensity information acquisition unit is recorded, and based on the recorded log, an access point connected at the current position of the moving object is recorded. A log analysis unit for analyzing the candidate,
The log analysis unit, when a plurality of access points of radio field intensity exceeding a predetermined threshold in the radio field intensity information acquisition unit is acquired, based on the trajectory of the moving object or the dispersion of the radio field intensity, the access point to connect Packet transmission device that determines Based on the log recorded in the log analysis unit, the number of packets to be duplicated in the duplication unit is increased or decreased according to the radio wave intensity at the position based on the position information of the moving object acquired by the position information acquisition unit. The packet transmitting apparatus according to claim 3, further comprising a packet number control unit for controlling . The wide area network packet is a packet encapsulated based on a connectionless protocol.
The packet transmission device according to claim 3 or 4. A packet receiving device according to claim 1 or 2,
A packet transmission device according to any one of claims 3 to 5,
A packet communication device comprising: The computer installed on the moving object
  Each of the mobile units includes a plurality of wireless communication units connected to the outside and the access point of the wide area communication network by wireless communication, and information indicating each of the wireless communication units is set. A wide area communication packet encapsulated with a wide area communication header including information indicating any of the plurality of wireless communication units is added to the short area communication network packet to which the wide area network header is added. Receiving over a wide area communication network by any of the plurality of wireless communication units,
  When the wide area network packet is received, the contents of the wide area network packet are temporarily stored in a memory, and the wide area network packet having the same content as the wide area network packet stored in the memory is stored in the memory. If received, delete the wide area network packet having the same content as the wide area network packet stored in the memory,
  When a wide area network packet having a content different from the storage content of the memory is received, the wide area network header is removed from the received wide area network packet, and the packet is returned to the narrow area network packet. ,
  The recovered local area network packet is transmitted to the internal destination included in the local area network header via the local area network.
Packet receiving method. The computer installed on the moving object
  Receiving a narrow-area communication network packet to which a narrow-area communication network header including information indicating an internal source and an internal destination in the mobile body is added via a narrow-area communication network,
  Duplicate the received narrow area network packet,
  To each of the copied plurality of narrow-area communication network packets, a wide-area communication network header including information indicating a wireless communication unit is added, and each is encapsulated as a wide-area communication network packet,
  Each of the encapsulated wide area network packets is connected to the access point of the wide area communication network by wireless communication, and each of the encapsulated wide area network packets is transmitted by the plurality of wireless communication sections. To the external destination included in the header for the wide area network via the wide area network.
In case,
  When transmitting each of the encapsulated wide area network packets, obtain information indicating the radio field intensity of the access point of the wide area network, obtain the position information of the mobile, the obtained mobile of the Location information and records a log in correspondence with the obtained radio field intensity, and, based on the recorded log, including analyzing the candidate of the access point to be connected at the current position of the mobile,
  When analyzing the candidate of the access point to be connected, when a plurality of access points of radio field intensity exceeding a predetermined threshold are obtained, based on the trajectory of the moving object or the dispersion of the radio field intensity, the access point to be connected is determined. decide
  Packet transmission method. The computer installed in the mobile unit may be a packet receiving device according to claim 1 or 2, a packet transmitting device according to any one of claims 3 to 5, or a computer according to claim 6. A communication program for functioning as the described packet communication device.