JP2007081456A - Converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically set the correspondence relation between apparatuses equipped with different communication protocols by utilizing a common communication protocol in a communication system including the apparatuses. <P>SOLUTION: A translator device 1 is provided in the communication system in which at least an IPv4 (Internet Protocol Version 4) apparatus and an IPv6 apparatus are provided and the IPv4 apparatus and the IPv6 apparatus operate in accordance with a BACnet (A Data Communication Protocol for Building Automation and Control Networks) protocol. The translator device 1 is provided with communication interface sections 11, 12 for relaying packet to be transmitted and received between the IPv4 and IPv6 apparatuses, and a storage section 13 for storing an IP (Internet Protocol) conversion table. A central processing section 14 acquires device IDs of the IPv4 and IPv6 apparatuses and an IPv4 address or an IPv6 address in accordance with the BACnet protocol, assigns the IPv6 address corresponding to the device ID of the IPv4 apparatus and the IPv4 address corresponding to the device ID of the IPv6 apparatus, and creates the IP conversion table. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a conversion device for converting and relaying packets communicated between equipment devices connected via the Internet, for example.

  Conventionally, as a technique for realizing communication between devices in which different communication protocols are implemented in a communication system using the Internet protocol, the following Patent Document 1 is known.

  For example, as shown in FIG. 20A, a communication system in which a relay device is provided between a plurality of IPv4 devices and a plurality of IPv6 devices, or a common communication line as shown in FIG. A communication system provided with a relay device connected together with an IPv4 device or IPv6 device, or a relay device connected to a DHCP (Dynamic Host Configuration Protocol) server as well as an IPv4 device or IPv6 device as shown in FIG. In the communication system provided with the relay device, the relay device performs conversion processing for enabling communication between the IPv4 device and the IPv6 device.

  As shown in FIG. 21, this relay apparatus includes an IPv4 communication interface unit 101 and an IPv6 communication interface unit 102, stores an IP conversion table in the storage unit 103, and refers to the table stored in the storage unit 103. Then, the destination address and the source address in the packet transmitted / received by the central processing unit 104 are rewritten.

The IP conversion table stored in the storage unit 103 registers a set of an IPv4 address and an IPv6 address for each device connected to the relay apparatus. Thereby, for example, when the IPv4 packet destined for the IPv6 device is received by the IPv4 communication interface unit 101, the relay device refers to the IP conversion table in the storage unit 103 by the central processing unit 104 and is included in the IPv4 packet. The source address is converted into an IPv6 address, and the destination IPv4 address is converted into an IPv6 address. Thereby, it is assumed that an IPv6 packet in which the destination and the transmission source are converted into an IPv6 address can be transmitted from the IPv6 communication interface unit 102.
Japanese Patent Application Laid-Open No. 2004-236096

  By the way, in a communication system using the Internet protocol as described above, communication between equipment devices that implement different communication protocols in a network of equipment that controls lighting equipment, air conditioning equipment, etc. in a home or building is realized. Is desired. In such equipment, for example, when equipment is installed in every place in a building, it is necessary to create an IP conversion table corresponding to a large-scale equipment.

  Therefore, when adding new equipment, etc., it is necessary to set the IP conversion table of all equipment manually, via the web, etc., and there is a problem that setting man-hours increase, and further, due to setting mistakes There may be a problem that communication is not possible.

  Therefore, the present invention has been proposed in view of the above-described circumstances, and in a facility-based communication system, a correspondence relationship between facility devices that implement different communication protocols is automatically determined using a common communication protocol. It is an object of the present invention to provide a conversion device that can be set as follows.

  The present invention includes at least a first device that transmits and receives a packet according to a first communication protocol and a second device that transmits and receives a packet according to a second communication protocol, and the first device and the second device are configured to perform first communication. The present invention relates to a conversion device that is provided in a communication system that operates according to a protocol higher than the protocol and the second communication protocol and converts address information of packets transmitted and received between the first device and the second device.

  The conversion apparatus includes a communication unit that relays packets transmitted and received between the first device and the second device, a device ID that identifies the first device and the second device in a higher communication protocol, and a first ID Storage means for storing a conversion table in which the address information of the communication protocol and the address information of the second communication protocol are registered in association with each other, the packet received by the communication means, and the packet is transmitted between the first device and the second device. A process of converting the address information of the first communication protocol into the address information of the second communication protocol with reference to the conversion table stored in the storage means when it is determined that the packet is communicated between Or a conversion means for converting the address information of the second communication protocol into the address information of the first communication protocol, and in order to solve the above-mentioned problem, According to the higher level communication protocol, the device ID of the first device and the second device included in the communication system and the address information of the first communication protocol of the first device having the device ID or the second device Address information of the second communication protocol is acquired, address information of the second communication protocol corresponding to the device ID of the first device, address information of the first communication protocol corresponding to the device ID of the second device, and To create a conversion table to be stored in the storage means.

  According to the conversion device of the present invention, in a facility-based communication system, a first device in which a different communication protocol is implemented using a communication procedure according to a higher-level communication protocol common to the first device and the second device. And the addresses of the second devices are acquired, assigned to the first devices and the second devices, and the correspondence between the device ID, the address of the first communication protocol, and the address of the second communication protocol is automatically expressed. A conversion table can be created.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a translator device 1 to which the present invention is applied includes an IPv4 device 2A, 2B (hereinafter simply referred to as “IPv4 device 2”) and an IPv6 device 3A, 3B. (Hereinafter, collectively referred to as “IPv6 device 3”), a communication system is configured.

  The IPv4 device 2 (first device) and the IPv6 device 3 (second device) transmit and receive packets according to the Internet protocol as the network layer protocol in the OSI reference model, respectively, and the IPv4 device 2 uses the Internet protocol version 4 (first device). 1), and the IPv6 device 3 is a device compatible with Internet Protocol version 6 (second communication protocol). These IPv4 equipment 2 and IPv6 equipment 3 are equipment such as disaster prevention equipment, crime prevention equipment, air conditioning equipment, electrical equipment, and lighting equipment in a communication system in a building, for the purpose of management and control of the equipment. A BACnet (A Data Communication Protocol for Building Automation and Control Networks) protocol, which is a common communication protocol for building automation systems, is implemented as an application layer protocol.

  Therefore, the IPv4 device 2 and the IPv6 device 3 are assigned a BACnet device ID that conforms to the BACnet protocol, which is a higher communication protocol than the Internet protocol, in addition to the IPv4 or IPv6 IP address according to the Internet protocol. .

  Accordingly, the IPv4 device 2 and the IPv6 device 3 perform transmission / reception processing according to the Internet protocol, analyze the IP header, receive a BACnet packet including BACnet data compliant with the BACnet protocol, and comply with the BACnet protocol. By performing the process, it operates as equipment in the building. The IPv4 device 2 and the IPv6 device 3 are set to function as an Icon (Intelligent Controller) in the BACnet protocol, and the BACnet device ID is set by a HIM (Human Interface Module) operated by a building administrator (not shown). Communication.

  The translator device 1 converts the IP address included in the BACnet packet transmitted / received between the IPv4 device 2 and the IPv6 device 3 using the BACnet device ID, and is transmitted / received between the IPv4 device 2 and the IPv6 device 3. It relays packets. As shown in FIG. 2, the translator device 1 includes an IPv4 communication interface unit 11 and an IPv6 communication interface unit 12 as communication units, and stores an IP conversion table in a storage unit (storage unit) 13. Then, the translator apparatus 1 refers to the IP conversion table stored in the storage unit 13 and rewrites the destination address and the source address in the IP header transmitted and received by the central processing unit 14 functioning as a conversion unit and a conversion table creation unit. As a result, the IPv4 device 2 compatible with IPv4 receives the BACnet packet including the IPv4 address, and the IPv6 device 3 compatible with IPv6 receives the BACnet packet including the IPv6 address.

  In the IP conversion table stored in the storage unit 13, a BACnet device ID, an IPv4 address, and an IPv6 address, which are identifiers in the BACnet protocol, are registered for every IPv4 device 2 and IPv6 device 3. When the central processing unit 14 receives the BACnet packet by the IPv4 communication interface unit 11 or the IPv6 communication interface unit 12, the central processing unit 14 converts the IP address by referring to the IPv4 address and the IPv6 address registered in the IP conversion table. The BACnet packet including the new IP header is created and transmitted from the IPv4 communication interface unit 11 or the IPv6 communication interface unit 12.

  As shown in FIG. 3, the BACnet packet transmitted and received in such a communication system has a BACnet area 21 in which BACnet protocol data is stored, and the BACnet area 21 includes a link (LINK) area 22. , An 8-byte UDP (User Datagram Protocol) area 23 that is a transport layer header, a 20-byte IP area 24 that is an IP layer header compliant with IPv4, and a 14-byte Ethernet (registered trademark) area 25 that is a link layer header. Is added.

  The BACnet area 21 includes a version area 31 in which version information of the BACnet protocol is stored, an invariable area including a control area 32 indicating the state of an NPCI (Network Protocol Control Information) area, an NPCI area 33 that is a variable area, an actual area It is divided into an APDU (Application Layer Protocol Data Unit) area 34 in which BACnet data including service types and control commands is stored.

  The NPCI area includes a DNET area 41 in which a BACnet device ID that is a final destination network address having a length of 2 octets is stored, a DLEN area 42 in which a final destination MAC (link) layer address having a length of 1 octet is stored, and a final destination MAC layer address DADR area 43 in which 2 octet length source network address is stored, SNET area 44 in which 2 octet length source network address is stored, SLEN area 45 in which 1 octet length source MAC layer address is stored, and source MAC layer address are stored SADR area 46, HC area 47 in which a hop count for preventing infinite circulation when passing through a router is stored, MT area 48 in which a network layer message that is router or network status information is stored, and a vendor ID are stored Consists of VID area 49 There.

  Next, an IP conversion table creation process of the translator device 1 in the communication system as described above will be described with reference to FIGS. 4, 5, and 6.

  First, when a new translator device 1 is connected to the communication line of the communication system, as shown in FIG. 4A, the translator device 1 displays information indicating that the IsI service is an APDU that inquires about the state of the connected device. The BACnet packet included in the area 34 is transmitted to the IPv4 device 2 by broadcast communication. At this time, the translator apparatus 1 performs broadcast communication by setting the destination address of the IP header to a broadcast address compliant with IPv4. Then, the IPv4 device 2 recognizes the BACnet packet including the WhoIs service by analyzing the APDU area 34 according to the BACnet protocol, stores its own IPv4 address as the source address in the IP area 24, and stores the SNET area A BACnet device ID is stored in 44, and a BACnet packet storing information representing an Iam service for notifying the connected device of its own state in the APDU area 34 is returned to the translator apparatus 1.

  As shown in FIG. 1, when the IPv4 device 2 is composed of an IPv4 device 2A and an IPv4 device 2B, the translator device 1 can receive a BACnet packet having an IPv4 address of “192.168.1.1” and a BACnet device ID of “1”. The BACnet packet with the IPv4 address “192.168.1.2” and the BACnet device ID “2” can be received. At this time, in the subsequent processing, the translator device 1 assigns a new IPv4 address to the IPv6 device 3 to which the IPv4 address is not assigned, so that the IP of the BACnet packet including information representing the Iam service received from the IPv4 device 2 The subnet of the IPv4 address stored in the area 24 (in this example, “192.168.1.X”) is acquired.

  Further, the translator device 1 broadcasts a BACnet packet including a broadcast address compliant with IPv4, includes a multicast address compliant with IPv6 in the IP region 24, and stores information indicating that it is a WhoIs service in the APDU region 34. Broadcast the BACnet packet including it. Then, the IPv6 device 3 recognizes the BACnet packet including the WhoIs service by analyzing the APDU area 34 according to the BACnet protocol, stores its own IPv6 address as the source address in the IP area 24, and stores the SNET area A BACnet device ID is stored in 44 and a BACnet packet in which information indicating the Iam service is stored in the APDU area 34 is returned to the translator apparatus 1.

  As shown in FIG. 1, when the IPv6 device 3 is composed of an IPv6 device 3A and an IPv6 device 3B, the translator device 1 uses the BACnet packet with the IPv6 address “Fe80 :: 0001: 0005” and the BACnet device ID “5”. Can be received, and a BACnet packet with an IPv6 address of “Fe80 :: 0001: 0006” and a BACnet device ID of “6” can be received.

  Thereby, the translator apparatus 1 can create the IP conversion table shown in FIG. Here, the existing device table of the IPv4 device 2 whose BACnet device ID is “1” only stores its own BACnet device ID and IPv4 address, and the IPv6 device 3 whose BACnet device ID is “6”. The existing device table only stores its own BACnet device ID and IPv6 address.

  Next, in this communication system, as shown in FIG. 5A, an IPv4 device 2 and an IPv6 device that have received a BACnet packet including information representing a WhoIs service and returned a BACnet packet including information representing an Iam service. 3 transmits a BACnet packet including information representing the WhoIs service to the translator apparatus 1 to the translator apparatus 1.

  When the BACnet packet including information indicating the WhoIs service is transmitted to the APDU area 34 from the respective IPv4 devices 2 having the BACnet device IDs “1” and “2”, the translator device 1 is connected to the IPv4 device connected to itself. Among the devices 2, an IPv4 address for which the BACnet device ID is “5” and an IPv4 address for which the BACnet device ID is “6” are assigned to the IPv4 addresses that are not used.

  The translator apparatus 1 includes the allocated IPv4 address “192.168.1.5” in the IP area 24, the BACnet device ID “5”, the BACnet packet including information indicating the Iam service in the APDU area 34, and the IPv4 address “192.168”. The IPv4 device 2 can receive the BACnet packet including the information “.1.6” in the IP area 24, the BACnet device ID “6” in the SNET area 44, and the information indicating the Iam service in the APDU area 34. Thereby, the translator apparatus 1 can set the IPv4 address for the IPv6 device 3 as the IP conversion table stored in the storage unit 13 as shown in FIG.

  When the BACnet packet including information indicating the WhoIs service is transmitted to the APDU area 34 from the IPv6 devices 3 having the BACnet device IDs “5” and “6”, the translator device 1 is connected to itself. Among the existing IPv6 devices 3, IPv6 addresses for which the BACnet device ID is “1” and IPv6 addresses for which the BACnet device ID is “2” are assigned to unused IPv6 addresses.

  The translator apparatus 1 includes the allocated IPv6 address “Fe80 :: 0001: 0001” in the IP area 24, the BACnet device ID “1”, the BACnet packet including information indicating the Iam service in the APDU area 34, and IPv6. The IPv6 device 3 receives the BACnet packet including the address “Fe80 :: 0001: 0002” in the IP area 24, the BACnet device ID “2” in the SNET area 44, and the information indicating the Iam service in the APDU area 34. be able to. Thereby, the translator apparatus 1 can set the IPv6 address for the IPv4 device 2 as the IP conversion table stored in the storage unit 13 as shown in FIG.

  In addition, the IPv4 device 2 and the IPv6 device 3 create the table at the same time as the IP conversion table creation processing by the translator device 1 in order to store the address table of the communication partner device stored in itself. To do.

  As illustrated in FIG. 6, for example, the IPv4 device 2 with the BACnet device ID “1” is assigned the BACnet device IDs “5” and “6” of the IPv6 device 3 and the IPv4 newly assigned by the translator device 1 from the translator device 1. When a BACnet packet including information indicating the Iam service including addresses “192.168.1.5” and “192.168.1.6” is received, a new BACnet device ID and IPv4 are added in addition to the set of its own BACnet device ID and IPv4 address. Memorize pairs with addresses. Further, the IPv4 device 2 with the BACnet device ID “1” receives the BACnet packet including the information indicating the Iam service from the IPv4 device 2 with the BACnet device ID “2”, and thereby receives the BACnet device ID “2” and the IPv4. Memorize pairs with addresses.

  Similarly, for example, the IPv6 device 3 having the BACnet device ID “6” receives the BACnet device IDs “1” and “2” of the IPv4 device 2 and the IPv4 address “Fe80: newly assigned by the translator device 1 from the translator device 1. : 0001: 0001 ”,“ Fe80 :: 0001: 0002 ”, and when a BACnet packet including information representing the Iam service is received, a new BACnet device ID is added in addition to the set of its own BACnet device ID and IPv6 address And a set of IPv6 addresses. Further, the IPv4 device 2 with the BACnet device ID “6” receives the BACnet packet including the information indicating the Iam service from the IPv6 device 3 with the BACnet device ID “5”, and thereby receives the BACnet device ID “5” and the IPv6. Memorize pairs with addresses.

  As another method for creating an IP conversion table and communicating the newly determined IPv4 address and IPv6 address to the IPv4 device 2 and the IPv6 device 3, as shown in FIG. When the BACnet packet including information indicating the Iam service is received by the translator device 1, a new IPv6 address is assigned to the BACnet device ID and the IPv4 address included in the BACnet packet, and the BACnet packet is assigned to the IPv6 device 3 You may send to. Conversely, even when a BACnet packet including information representing the Iam service is received from the IPv6 device 3, the IP conversion table can be created by transmitting the BACnet packet including a new IPv4 address to the IPv4 device 2.

  As shown in FIG. 8, the translator device 1 has a destination included in the IP area 24 of the BACnet protocol from the IPv4 device 2 when the IPv4 device 2 and the IPv6 device 3 are connected to the translator device 1. If the IPv4 address is “192.168.1.10”, the IPv4 address of the destination is converted to the IPv6 address “fe80 :: 200: 0001” by referring to the IP conversion table, and the IPv6 device 3 side Can be sent. Conversely, even when a BACnet packet having the IPv4 device 2 as the transmission destination is received from the IPv6 device 3, the translator device 1 can convert the IPv6 address of the transmission destination into an IPv4 address.

  For example, as illustrated in FIG. 9, when the translator apparatus 1 receives a BACnet packet including a broadcast address in the IP area 24 from the IPv4 device 2, the translator device 1 converts the broadcast address into a multicast address, Can be sent to. Conversely, when the translator device 1 receives a BACnet packet including a multicast address in the IP area 24 from the IPv6 device 3, the translator device 1 can convert the multicast address into a broadcast address and transmit it to the IPv4 device 2.

  As described above, according to the translator device 1 to which the present invention is applied, the communication procedure (WhoIs service, Iam service) according to the BACnet protocol common to the IPv4 device 2 and the IPv6 device 3 is performed in the equipment communication system. The IPv4 address and the IPv6 address of the IPv4 device 2 and the IPv6 device 3 in which different communication protocols are implemented are obtained, and an IPv4 address that is not currently used is assigned to the IPv6 device 3, and an IPv6 address that is not currently used. Can be automatically assigned to the IPv4 device 2 to automatically create an IP conversion table indicating the correspondence between the BACnet device ID, the IPv4 address, and the IPv6 address. In other words, by using a communication procedure of a higher-level protocol such as the Internet protocol, an address used in the general-purpose protocol is acquired and a new address is assigned. Communication between devices that implement the protocol can be realized.

  Further, the translator device 1 communicates the contents of the automatically created IP conversion table to the other IPv4 device 2 and the IPv6 device 3, and the IPv4 device 2 and the IPv6 device 3 communicate with each other according to the BACnet protocol. be able to.

  Next, a method for assigning new IPv4 addresses and IPv6 addresses in the translator apparatus 1 described above after creating an IP translation table as shown in FIG. 4B will be described. This address assignment process may be a static method in which a user manually inputs an IPv4 address and an IPv6 address, and the existence of the IPv4 device 2 is confirmed using ARP (Address Resolution Protocol) and dynamically assigned. Alternatively, the existence of the IPv6 device 3 may be confirmed using ICMP (Internet Control Message Protocol) and a link local address may be dynamically assigned. A translator can acquire an IPv6 prefix by a router, and can also assign a global address by acquiring a MAC address of an IPv4 device by ARP.

  That is, when assigning an IPv4 address to the IPv6 device 3, as shown in FIG. 10A, first, the translator device 1 receives a BACnet packet including information representing an Iam service in response to a BACnet packet including information representing a WhoIs service. Upon reception, an IPv4 address (eg, 192.168.1.5) that is not used in the subnet of the IPv4 address included in the IP area 24 of the BACnet packet is selected (step S1). Next, the translator device 1 broadcasts a request that conforms to the ARP, obtains a response from all IPv4 devices 2 and checks the existence (step S2), and has already registered the IPv4 address selected in step S1. Allocation is performed corresponding to the IPv6 address (step S3).

  On the other hand, when assigning an IPv6 address to the IPv4 device 2, as shown in FIG. 10B, first, the translator apparatus 1 receives a BACnet packet including information indicating an Iam service in response to a BACnet packet including information indicating a WhoIs service. Upon reception, an unused IPv6 address (eg, fe80 :: 0001: 0001) is selected (step S11). Next, the translator device 1 distributes ping data compliant with ICMP to check the existence of all IPv6 devices 3 (step S12), and the IPv6 address selected in step S11 corresponds to the already registered IPv4 address. (Step S13).

  As described above, after selecting an IPv4 address and an IPv6 address that are not currently used, the IPv4 address and the IPv6 address of the IPv4 device 2 and the IPv6 device 3 that are currently communicating are selected using a technique such as ARP or ICMP. It is confirmed whether or not there is a duplication with the IPv4 address and the IPv6 address, and when there is no duplication, a new IPv4 address and an IPv6 address can be set. When the selected IPv4 address and IPv6 address are duplicated, another IPv4 address and IPv6 address can be selected.

  Next, description will be given of preventing address duplication when there is a device that has newly entered the communication system due to, for example, equipment expansion. For example, as shown in FIG. 11A, from the state in which two IPv6 devices 3 to which the IPv4 addresses “192.168.1.1” and “192.168.1.2” are assigned are connected to the translator device 1, respectively. A case will be described in which an IPv4 device 2 to which “192.168.1.1” is assigned as an initial setting newly enters and is connected to the translator device 1.

  In this case, as shown in FIG. 12 for the process at the time of new entry, it is set to broadcast an ARP request from the IPv4 device 2 to the translator device 1 at the time of new entry. It should be noted that even if the newly entering device is the IPv6 device 3, the setting is made so that ICMP ping data is distributed at the time of new entry. When the translator device 1 receives the ARP request, the translator device 1 stores the IPv4 address “192.168.1.1” included in the ARP request received in step S21 in the storage unit 13 in step S22. It is determined whether it is an IPv4 address registered in the IP conversion table. Thereby, it is determined whether or not the IPv4 address of the newly entered IPv4 device 2 has already been assigned.

  If the received IPv4 address “192.168.1.1” is not included in the IP translation table, the translator device 1 registers the received IPv4 address in the IP translation table in step S23, and in step S27. Start communication operation. Even when this communication operation is started, an IPv6 address that is not used is allocated to the newly entered IPv4 device 2 in order to realize communication with the IPv6 device 3.

  On the other hand, when it is determined that the IPv4 address “192.168.1.1” of the newly entered IPv4 device 2 has already been assigned as shown in FIG. 11B, the process proceeds to step S24, and the newly entered IPv4 device 2 The operation of the IPv6 device 3 that overlaps with is stopped. At this time, the translator device 1 transmits to the IPv6 device 3 a BACnet packet in which information indicating services such as operation stop or prohibition of use of the IPv4 address “192.168.1.1” in accordance with the BACnet protocol is stored in the APDU area 34. Note that not only the operation of the IPv6 device 3 is stopped using the BACnet protocol, but another device management protocol or the like may be used.

  In the next step S25, as shown in FIG. 11 (c), the translator device 1 uses the IPv4 address “192.168.1.1” assigned to the IPv6 device 3 whose operation has been stopped as the IPv4 device 2 that newly entered. The IPv4 address “192.168.1.1” is set, and the IPv4 address of the IPv6 device 3 to which the duplicate IPv4 address is assigned is changed to a new IPv4 address “192.168.1.10”.

  In the next step S26, the translator device 1 uses the BACnet protocol Iam service or the like in order to notify the other IPv4 device 2 and IPv6 device 3 of the new change of the IP conversion table. The table in the IPv4 device 2 and the IPv6 device 3 is changed, and communication is started in step S27.

  In this way, the translator device 1 causes duplication of the IPv4 address or the IPv6 address when a new device enters, or when another device enters a new device while there is a device that has been temporarily unavailable for maintenance. Even in this case, the situation can be avoided.

  Next, after creating an IP translation table as shown in FIG. 4B, another method for assigning new IPv4 addresses and IPv6 addresses will be described.

  As shown in FIG. 13, in this address assignment process, the existing IPv4 device 2 and the IPv6 device 3 and the translator device 1 in which the DHCP server function which is an automatic IP address assignment function is installed in the HUB 51 which is a concentrator. A case in which the other IPv4 device 2 and the IPv6 device 3 are newly connected to the translator device 1 via the HUB 51 will be described.

  The translator device 1 associates an IPv4 address and an IPv6 address with each BACnet device ID of “1” to “50” as shown in FIG. 14 in an area different from the IP conversion table of the storage unit 13 in advance. The pool table is stored. When detecting that the newly entered IPv4 device 2 and the IPv6 device 3 are connected to the HUB 51, the translator device 1 sends a BACnet packet including information representing the WhoIs service to the newly entered IPv4 device 2 and Output to IPv6 device 3.

  When the newly entered IP device implements the BACnet protocol, the translator device 1 can acquire the BACnet device ID and the IP address by receiving the BACnet packet including information representing the Iam service. On the other hand, when the newly entered IP device does not implement the BACnet protocol, the DHCP table is referred to perform DHCP processing and IP address assignment is performed, and newly entered IPv4 device 2 and IPv6 device are performed by ARP or ICMP. 3 is confirmed to be an IP address already used. Thereby, the translator apparatus 1 performs the IP address assignment process shown in FIG. 16 from the IP conversion table including the BACnet device ID and the IP address of the existing IPv4 equipment 2 and IPv6 equipment 3 as shown in FIG. As shown in FIG. 17, the IPv4 address and IPv6 address of the newly entered IPv4 device 2 and IPv6 device 3 are acquired.

  In the processing shown in FIG. 16, first, when a DHCP request is transmitted from the newly entered IPv4 device 2 and IPv6 device 3 to the translator device 1, the translator device 1 refers to the pool table by the DHCP server function, and creates a new IPv4. The DHCP response to which the address “192.168.1.1” is assigned is transmitted to the newly entered IPv4 device 2, and the DHCP response to which the new IPv6 address “fe80 :: bac0: 2” is assigned is transmitted to the newly entered IPv6 device 3. Then, the newly entered IPv4 device 2 transmits an ARP with the assigned IPv4 address “192.168.1.1” to the translator device 1 to confirm that it does not overlap with the IPv4 addresses of the existing IPv4 device 2 and the IPv6 device 3. After confirming, the newly entered IPv6 device 3 transmits ICMP to the translator device 1 to confirm that it does not overlap with the IPv6 addresses of the existing IPv4 device 2 and IPv6 device 3. As a result, as shown in FIG. 17, the IPv4 address “192.168.1.1” is assigned to the newly entered IPv4 device 2, and the IPv6 address “fe80 :: bac0: 2” is assigned to the newly entered IPv6 device 3. Can be registered in the IP conversion table.

  Next, the translator device 1 assigns an IPv6 address to the newly entered IPv4 device 2 and assigns an IPv4 address to the newly entered IPv6 device 3, in response to the WhoIs service from the IPv4 device 2 and the IPv6 device 3. The new IPv4 address, IPv6 address, and Iam service are used for notification. As a result, as shown in FIG. 17, the IPv4 address “fe80 :: bac0: 1” is assigned to the newly entered IPv4 device 2, and the IPv4 address “192.168.1.2” is assigned to the newly entered IPv6 device 3. IP conversion table can be created.

  In addition, another address assignment process using the DHCP server function is performed when the IPv4 device 2 and the IPv6 device 3 implement the BACnet protocol, and the unique function BACnet device ID is assigned using the DHCP protocol option function. It can also be assigned to a newly entered IPv4 device 2 and IPv6 device 3. In this address assignment process, as shown in FIG. 18, a BACnet device ID unique to the translator apparatus 1 is requested by including a command for acquiring the BACnet device ID in the DHCP response of the newly entered IPv4 device 2. On the other hand, the translator apparatus 1 selects a BACnet device ID that is not allocated to the existing IPv4 device 2 and the IPv6 device 3 with reference to the pool table according to the request included in the DHCP request, and the unique BACnet device ID “1”. ”Including the unique BACnet device ID“ 2 ”is transmitted to the newly entered IPv6 device 3.

  Accordingly, an IP conversion table in which a BACnet device ID as shown in FIG. 19 is added to the IP conversion table shown in FIG. 17 can be created.

  The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the design and the like as long as the technical idea according to the present invention is not deviated from this embodiment. Of course, it is possible to change.

It is a block diagram which shows the communication system containing the translator apparatus to which this invention is applied. It is a block diagram which shows the internal structure of the translator apparatus to which this invention is applied. It is a figure which shows the structure of a BACnet packet. (A) shows the operation of acquiring the addresses of the IPv4 device and IPv6 device connected to the translator device, and (b) shows the IP conversion table, the device table stored in the IPv4 device, and stored in the IPv6 device. Shows the device table. (A) shows the operation of communicating addresses assigned to the IPv4 device and IPv6 device connected to the translator device, and (b) shows the IP conversion table. It is a figure which shows the other operation | movement which notifies the address allocated to the IPv4 apparatus connected to the translator apparatus, and the IPv6 apparatus. It is a figure which shows the other operation | movement which notifies the address allocated to the IPv4 apparatus connected to the translator apparatus, and the IPv6 apparatus. It is a figure explaining operation | movement of the translator apparatus in the case of performing unicast communication by the IPv4 apparatus and the IPv6 apparatus. It is a figure explaining operation | movement of the translator apparatus in the case of performing broadcast communication by an IPv4 apparatus, and the case of performing multicast communication by an IPv6 apparatus. (A) is a flowchart which shows the process which allocates an IPv4 address to an IPv6 apparatus, (b) is a flowchart which shows the process which allocates an IPv6 address to an IPv4 apparatus. (A) is an example of a communication system, (b) is an explanatory diagram in which there is a newly entered IPv4 device in the communication system of (a), and (c) is a communication system after performing address assignment processing. It is explanatory drawing of. It is a flowchart for preventing assigning a duplicate IP address when there is a newly entered device. It is a block diagram of the communication system which has a translator apparatus provided with the DHCP server function. It is a figure which shows an example of the pool table memorize | stored in a translator apparatus. It is a figure which shows another IP conversion table. It is a flowchart which shows the process which acquires an IP address by a DHCP server function. It is a figure which shows the IP conversion table comprised by acquiring an IP address by a DHCP server function and a BACnet protocol. It is a flowchart which shows the process which acquires BACnet device ID by a DHCP server function. It is a figure which shows the IP conversion table comprised by acquiring BACnet device ID by a DHCP server function. It is a block diagram which shows the structure of the conventional translator apparatus. It is a figure which shows the structure of the conventional communication system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Translator apparatus 2 IPv4 apparatus 3 IPv6 apparatus 11 Communication interface part for IPv4 12 Communication interface part for IPv6 13 Memory | storage part 14 Central processing part 21 BACnet area | region 24 IP area | region 51 HUB

Claims (5)

At least a first device that transmits and receives packets in accordance with a first communication protocol and a second device that transmits and receives packets in accordance with a second communication protocol, wherein the first device and the second device include the first communication protocol and the In a conversion device that is provided in a communication system that operates according to a protocol higher than the second communication protocol, and that converts address information of packets transmitted and received between the first device and the second device,
Communication means for relaying packets transmitted and received between the first device and the second device;
A device ID for identifying the first device and the second device in the upper communication protocol, the address information of the first communication protocol, and the address information of the second communication protocol are registered in association with each other. Storage means for storing the conversion table;
When the communication means receives the packet and determines that the packet is a packet communicated between the first device and the second device, refer to the conversion table stored in the storage means. A process of converting the address information of the first communication protocol into the address information of the second communication protocol, or a conversion of converting the address information of the second communication protocol into the address information of the first communication protocol Means,
According to the higher-level communication protocol, the device IDs of the first device and the second device included in the communication system, and the address information of the first communication protocol of the first device having the device ID or the first Address information of the second communication protocol of two devices, and address information of the second communication protocol corresponding to the device ID of the first device and the second information corresponding to the device ID of the second device. A conversion table creating means for allocating address information of one communication protocol and creating a conversion table to be stored in the storage means.   The conversion table creating unit assigns address information of the second communication protocol corresponding to the device ID of the first device and address information of the first communication protocol corresponding to the device ID of the second device. Before checking whether there is a device to which the address information of the second communication protocol is assigned, whether to have a device to which the address information of the first communication protocol is assigned exists. The conversion device according to claim 1, wherein:   When there is a newly connected device in the communication system, the conversion table creating means causes the address information of the newly connected device to overlap with the address information assigned to the existing device. 2. The conversion apparatus according to claim 1, wherein new address information is assigned to the address information of one of the devices.   In accordance with DHCP (Dynamic Host Configuration Protocol), the conversion table creating means includes the address information of the second communication protocol corresponding to the device ID of the first device and the first information corresponding to the device ID of the second device. The conversion apparatus according to claim 1, wherein address information of the communication protocol is assigned.   The said conversion table preparation means acquires the device ID of the said 1st apparatus and the said 2nd apparatus using the function of the option contained in DHCP (Dynamic Host Configuration Protocol). Conversion device.

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