JP2006100952A - Communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire apparatus information in an electric lamp line network efficiently. <P>SOLUTION: The communication device comprises a first communication device 101, a second communication device 102, a second communication device 103, and a second communication device 104. Since the second communication device 104 trying to acquire the apparatus information in a network recognizes the communication device in the network by acquiring index information of the first communication device 101, apparatus information in the network can be acquired efficiently. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the power line network, the present invention has a plurality of communication devices to which one or a plurality of network devices are connected, and the communication devices control communication in the network so as to transmit / receive data of the network devices to / from each other, Each communication device relates to device information acquisition of network devices in the network.

  Conventionally, there are unicast transmissions that communicate individually between communication devices and other communication devices in a communication network, and broadcast transmissions that broadcast to all communication devices, and are specified as different control methods due to the nature of each protocol. It was often done.

  For example, in unicast transmission, by sending back acknowledgment information (ACK) from the information receiving communication device and retransmitting the unreachable information, the information receiving communication device from the information transmitting communication device In general, a method of reliably transmitting data between the two is used.

  Also, in broadcast transmission, as a method of improving the reliability, broadcast transmission is performed from the command requesting device, the response packet circulates between all the devices that have received the broadcast communication, and the broadcast communication reception status of each receiving device Is finally transmitted to the command requesting device, so that the command receiving device that could not receive the broadcast communication is identified and retransmitted (see, for example, Patent Document 1).

As a method for improving reliability in broadcast transmission, the command requesting device informs a plurality of command receiving devices in advance of the timing for returning a response to the command to the command requesting device before performing broadcast communication. A plurality of command receiving devices that have received the information command transmit the responses of their own devices in a predetermined time and order, so that the command requesting device can determine from the order of the command receiving devices that have responded, It is possible to determine whether or not the broadcast communication has been correctly received (see, for example, Patent Document 2).
JP 2003-60701 A JP 2002-171257 A

  However, in the power line network, the communication environment is inferior due to its transmission path characteristics. Therefore, in order to improve communication quality in unicast transmission, a technique such as DMT (Discrete Multi Tone) is used on the transmitting side and the receiving side. It is necessary to perform communication after preparing individual communication parameters for each combination on the transmission side and reception side in advance. For this reason, there is a problem that the overhead for setting communication parameters is large, and it takes time to acquire device information.

  In broadcast transmission, instead of requiring individual communication parameters, it is necessary to use diversity techniques and modulation schemes that improve error resilience, and large error corrections that are redundant. It had the subject of consuming a lot of bandwidth.

  Furthermore, each communication device has a problem that the other party of unicast transmission cannot secure reliability at the time of broadcast transmission unless other communication devices existing in the power line network are known in advance.

  In the above-described conventional example, in the power line communication, the method in which the response packet circulates between the apparatuses that have received the broadcast communication has a problem that the packet overhead is very large and the communication band is consumed greatly.

  In addition, specifying the response response order to a plurality of command devices in advance complicates the management of the response order, and as the network scale increases, the load on the control device increases and system performance and system efficiency decrease. There is a problem.

  In order to achieve the above object, according to the present invention, a plurality of communication devices are connected via a network, each communication device manages at least one network device, and communication between network devices via a network is performed. A communication apparatus that performs index information acquisition means for acquiring index information indicating information of communication apparatuses existing in the network, and manages information (hereinafter referred to as terminal information) related to network devices managed by the own apparatus, A terminal information management means for transmitting information to another communication apparatus; and a terminal information acquisition means for acquiring terminal information from the other communication apparatus, wherein the terminal information acquisition means is a broadcast including a return request for terminal information. Sends to other communication devices, and based on the index information Provided to the communication device the device information obtaining means and performing a unicast communication including the return request of the terminal information to the back of which was not communication apparatus null information.

  A plurality of communication devices are connected via a network, and each communication device manages at least one network device and performs communication between network devices via the network, and exists in the network. Index information acquisition means for acquiring index information indicating information on the communication device to be used, terminal information management means for managing information on network devices managed by the own device, and transmitting terminal information to other communication devices, and others Terminal information acquisition means for acquiring terminal information from the other communication apparatus, the terminal information acquisition means performs broadcast transmission including a return request for terminal information to other communication apparatuses, and the terminal based on the index information Returning terminal information to a communication device that did not return information The communication apparatus characterized by performing unicast communication including a request, without generating excessive traffic in the network, the effect can be acquired terminal information efficiently.

  In addition, management of information in the network more than necessary by a communication device further comprising index information management means for managing index information and notifying index information in response to a request from the index information acquisition means And there is an effect of reducing the load on the communication device.

  The terminal information acquisition means performs unicast communication using the communication parameter when the communication parameter is known, and uses broadcast communication when the communication parameter is not known. Thus, a communication device characterized in that communication including a return request for terminal information is performed, and the terminal information can be efficiently acquired without generating unnecessary traffic in the network.

  Also, the broadcast transmission frame includes an address on the network of at least one communication device that needs to return terminal information, and the terminal information management means includes the address on the network of the own communication device in the frame. If the communication apparatus is characterized in that the terminal information is returned only when the terminal information is received, the terminal information can be efficiently acquired without generating unnecessary traffic in the network.

  The broadcast transmission frame includes an attribute of terminal information that needs to be returned, and the terminal information management means returns the terminal information having the attribute described in the frame. As a result, the terminal information can be efficiently acquired without generating unnecessary traffic in the network.

  Further, when the terminal information of the communication apparatus is updated, the terminal information management means notifies the index information management means of update information indicating that the terminal information has been updated, and the terminal information acquisition means Based on the communication device, the latest terminal information is acquired by acquiring the updated terminal information and the terminal information collected by the other or the own communication device last time. The terminal information can be efficiently acquired without generating unnecessary traffic in the network.

(Embodiment 1)
FIG. 1 is a configuration diagram of a terminal information acquisition apparatus having a network configuration according to Embodiment 1 of the present invention.

  In FIG. 1, a first communication device 101 is a communication device that controls the inside of a network as a parent device in the network and holds index information, and includes a second communication device 102, a second communication device 103, and a second communication device. The communication device 104 is a slave unit in the network.

  In FIG. 2, the configuration of the first communication device 201 and the second communication device 202 will be described. The first communication apparatus 201 manages the address information of the communication apparatus in the network, the change in terminal change information, and the terminal information holding flag in the network as index information in the network shown in FIG. 5 described below. Index information management unit 2011, a function of acquiring index information from index information management unit 2011 when acquiring the latest terminal information in the network, and index information for the communication device that acquired the terminal information in the previous network A terminal having an index information acquisition unit 2012 having a function of requesting acquisition of terminal information, a function of managing network devices managed by itself, and a function of analyzing frames and transmitting requested terminal information Information management unit 2013 The function of the terminal information acquisition request to the device, in the case of retransmission, the terminal information acquiring unit 2014 having a function of determining whether to broadcast transmit unicast transmission, and a transmitting and receiving unit 2015 of the frame. The second communication device 202 has a function of acquiring index information from the first communication device when acquiring the latest terminal information in the network, and index information for the communication device that acquired the terminal information in the previous network. And an index information acquisition unit 2021 having a function of requesting acquisition of terminal information, a function of managing network devices managed by itself, and a function of analyzing frames and transmitting requested terminal information A terminal information management unit 2022; a terminal information acquisition unit 2023 having a function of requesting terminal information acquisition to a communication device; and a function of determining whether to perform unicast transmission or broadcast transmission in the case of retransmission; Part 2024.

  Here, the structure of the index information is shown using FIG. Area 501 stores the address of a communication device existing in the network. An area 502 is an area in which a flag is set when the terminal information held by the communication apparatus changes. An area 503 is an area for storing the valid time of terminal information in the network. The area 503 may be the latest terminal information acquisition time in the network. An area 5011 holds the address of the first communication apparatus 101, an area 5021 holds update information of the first communication apparatus 101, and an area 5031 holds the latest terminal information in the network. If so, it is an area in which the terminal information valid time is stored. An area 5012 holds the address of the second communication apparatus 102, an area 5022 holds update information of the second communication apparatus 102, and an area 5032 holds the latest terminal information in the network. If so, it is an area in which the terminal information valid time is stored. The area 5013 holds the address of the second communication apparatus 103, the area 5023 holds update information of the second communication apparatus 103, and the area 5033 holds the latest terminal information in the network. If so, it is an area in which the terminal information valid time is stored. An area 5014 holds the address of the second communication apparatus 104, an area 5024 holds update information of the second communication apparatus 104, and an area 5034 holds the latest terminal information in the network. If so, it is an area in which the terminal information valid time is stored.

  The network device 105 is connected to the first communication device 101, the network device 106 is connected to the second communication device 102, and the network device 107 and the network device 108 are connected to the second communication device 103. The network device 109 and the network device 110 are connected to the second communication device 104. Further, the first communication device 101 holds terminal information of the network device 105, and the second communication device 102 holds terminal information of the network device 106 and the network device 107. The device 103 holds terminal information of the network device 108, and the second communication device 104 holds terminal information of the network device 109 and the network device 110.

  Here, the configuration of the terminal information is shown using FIG. An area 601 stores network device address information. In the area 602, device information is stored. Here, the device information includes the type of connected device, the connection time, and the like. The area 6031 stores the address of the network device 106, and the areas 6032 and 6033 store apparatus information. An area 6041 stores the address of the network device 107, and areas 6042 and 6043 store apparatus information.

  The operation of the terminal information acquisition method in the network configured as described above will be described below with reference to FIGS. 2, 3, 4, and 5. FIG. In unicast transmission, it is assumed that a communication apparatus that is an information receiving destination returns a response frame (ACK) to a frame received without error.

  In step S <b> 301, the second communication device 104 attempting to collect terminal information in the power line network requests the first communication device 101 to obtain index information. At this time, the index information acquisition unit 2021 issues a request, and a frame is transmitted from the transmission / reception unit 2024.

  Next, in step S302, the index information management unit 2011 of the first communication apparatus 101 transmits index information to the second communication apparatus 104 via the transmission / reception unit 2015.

  In step S303, the second communication device 104 manages the received frame by the index information acquisition unit 2021, and knows the existence of all other communication devices existing in the network based on the index information from the first communication device 101. The terminal information acquisition unit 2023 broadcasts a frame for acquiring terminal information to communication devices existing in the network.

  At this time, the structure of the broadcast frame is as shown in FIG. A power line communication frame is composed of a frame control and a payload, and is composed of an area 402 for storing terminal information to be acquired in the payload and an area 403 for storing the address of a communication apparatus for which terminal information is to be acquired. When nothing is stored in the areas 402 and 403, all terminal information of all communication apparatuses is acquired.

  In step S304, the terminal information acquisition unit 2023 of the second communication apparatus 102 that has received the broadcast frame analyzes the payload area 401 of the broadcast frame, and the DVD recorder is designated as the network device type in the area 402. Since the network device 106 connected to the second communication device 102 is a DVD recorder, the management unit 2022 returns the requested terminal information to the second communication device 104. Note that the information included in the area 402 may include network device addresses and names, information that categorizes and specifies network devices in addition to device types.

  In step S <b> 305, the first communication apparatus 101 that has received the broadcast frame sends a reply to the second communication apparatus 104, but no information has arrived at the second communication apparatus 104. Such a state includes, for example, the case where the communication device 101 returns the terminal information to the communication device 104 and the transmission of another communication device at the same time, and the terminal information returned due to the collision is discarded. Further, the second communication device 103 is in a state where it cannot receive a broadcast frame.

  In step S306, the terminal information acquisition unit 2023 of the second communication device 104 compares the terminal information of the communication device that has returned within a certain effective time with the index information, and determines which communication device has returned the response. Then re-send processing. In the example, the reply from the second communication device 102 can be acquired, and the reply from the first communication device 101 and the second communication device 103 cannot be acquired. At this time, the terminal information acquisition unit 2023 of the second communication device 104 holds the number of communication devices that have not returned, and communication parameters for performing unicast transmission between the communication devices that have communicated before. Broadcast transmission is performed. The address of the second communication device 103 and the address of the first communication device 101 that could not be acquired are stored in the payload area 403 of the broadcast frame, and broadcast transmission is performed.

  In step S307, the terminal information management unit 2022 of the second communication apparatus 102 analyzes the broadcast frame and does not send a reply because the address of the local station is not stored. Since the terminal information management unit 2013 of the first communication device 101 and the terminal information management unit 2022 of the second communication device 103 store their own addresses, the terminal information is transmitted to the second communication device 104.

  Next, in step S308, after acquiring the terminal information in the network, the terminal information management unit 2022 of the second communication device 104 holds that the terminal information in the network is held for the first communication device 101. Notice. The index information management unit 2011 of the first communication device 101 holds it as shown in FIG. 5 so that it can be understood that the second communication device 104 holds the terminal information in the network when notified. A flag is set in the index information area 5034 of the entire network.

  In step S309, after the second communication device 104 collects terminal information in the network, the terminal information management unit 2013 or the terminal information management unit 2022 of the communication device existing in the network holds the own station. When the terminal information changes, the first communication apparatus 101 is notified that the terminal information of the own station has changed. Here, it is assumed that the terminal information held by the second communication apparatus 102 has changed. The terminal information management unit 2022 of the second communication apparatus 102 notifies the first communication apparatus 101 that the terminal information held by the local station has changed. The index information management unit 2011 of the first communication device 101 sets a flag for an area 5022 shown in FIG. 5 in order to indicate that the index information has changed in the terminal information of the second communication device 102.

  From the above process, terminal information can be efficiently acquired without generating unnecessary traffic in the power line network.

(Embodiment 2)
Since the network configuration is the same as that of the first embodiment, a description thereof will be omitted.

  The operation of the terminal information acquisition method in the network configured as described above will be described below with reference to FIG. In unicast transmission, it is assumed that a communication apparatus that is an information receiving destination returns a response frame (ACK) to a frame received without error.

  In step S <b> 701, the second communication device 104 attempting to collect terminal information in the power line network requests the first communication device 101 to obtain index information. At this time, the index information acquisition unit 2021 issues a request, and a frame is transmitted from the transmission / reception unit 2024.

  In step S <b> 702, the index information management unit 2011 of the first communication apparatus 101 transmits index information to the second communication apparatus 104.

  In step S <b> 703, the second communication device 104 manages the received frame with the index information acquisition unit 2021, and knows the existence of all other communication devices existing in the network based on the index information from the first communication device 101. A frame for acquiring terminal information is broadcast to a communication apparatus existing in the network. At this time, the structure of the broadcast frame is as shown in FIG. A power line communication frame is composed of a frame control and a payload, and is composed of an area 402 for storing terminal information to be acquired in the payload and an area 403 for storing the address of a communication apparatus for which terminal information is to be acquired. When nothing is stored in the areas 402 and 403, all terminal information of all communication apparatuses is acquired.

  In step S704, the terminal information acquisition unit 2012 of the first communication device 101 that has received the broadcast frame and the terminal information acquisition unit 2022 of the second communication device 102 analyze the payload area 401 of the broadcast frame and store the second information in the area 403. The terminal information management unit 2022 returns the requested terminal information to the second communication device 104 since the own communication device 102 address is included.

  In step S <b> 705, the second communication device 103 that has received the broadcast frame sends a reply to the second communication device 104, but no information has arrived at the second communication device 104.

  In step S706, the terminal information acquisition unit 2023 of the second communication device 104 compares the terminal information of the communication device that has returned within a certain effective time with the index information, and determines which communication device has returned the response. Then re-send processing. In the example, replies from the first communication device 101 and the second communication device 102 can be acquired, and replies from the second communication device 103 cannot be acquired. At this time, if the terminal information acquisition unit 2023 of the second communication device 104 holds a unicast transmission parameter with the second communication device 103, the terminal information acquisition unit 2023 performs retransmission by unicast transmission.

  In step S <b> 707, the terminal information management unit 2022 of the second communication device 103 transmits terminal information to the second communication device 104.

  Next, in step S708, after the terminal information management unit 2022 of the second communication device 104 acquires the terminal information in the network, the terminal information in the network is held at the first communication device 101. Notice. The index information management unit 2011 of the first communication device 101 holds it as shown in FIG. 5 so that it can be understood that the second communication device 104 holds the terminal information in the network when notified. A flag is set in the index information area 5034 of the entire network.

  In step S709, after the second communication device 104 collects terminal information in the network, the terminal information management unit 2013 or the terminal information management unit 2022 of the communication device existing in the network holds it. When the terminal information changes, the first communication apparatus 101 is notified that the terminal information of the own station has changed. Here, it is assumed that the terminal information held by the second communication apparatus 102 has changed. The terminal information management unit 2022 of the second communication apparatus 102 notifies the first communication apparatus 101 that the terminal information held by the own station has changed. The index information management unit 2011 of the first communication device 101 sets a flag for an area 5022 shown in FIG. 5 in order to indicate that the index information has changed in the terminal information of the second communication device 102.

  Through the above process, terminal information can be acquired more efficiently without generating more traffic than necessary in the power line network, compared to the case of using broadcast by using the result of past communication.

(Embodiment 3)
Since the network configuration is the same as that of the first embodiment, the description is omitted.

  The operation of the terminal information acquisition method in the network configured as described above will be described below with reference to FIG. In unicast transmission, it is assumed that a communication apparatus that is an information receiving destination returns a response frame (ACK) to a frame received without error.

  FIG. 8 shows an example in which terminal information in the power line network managed by the terminal information management unit 2022 of the second communication apparatus 104 is valid and can be used within a certain period of time.

  In step S801, the index information acquisition unit 2021 of the second communication device 103 requests index information from the first communication device 101 in order to collect terminal information in the power line network.

  In step S <b> 802, the index information management unit 2011 of the first communication apparatus 101 transmits the held index information to the second communication apparatus 103.

  In step S803, the index information acquisition unit 2021 of the second communication device 103 knows from the acquired index information that the second communication device 104 holds the terminal information in the network. For example, a terminal information acquisition request in the network is transmitted to the second communication device 104. If a certain time has passed, the above sequence is not performed.

  In step S804, the index information acquisition unit 2021 of the second communication device 104 transmits the index information, and the terminal information management unit 2022 transmits the terminal information in the network held to the second communication device 103.

  In step S805, the index information acquisition unit 2021 of the second communication device 103 refers to the index information acquired from the first communication device 101 and the terminal information acquired from the second communication device 104, and performs the second communication. The terminal information newly changed from the terminal information in the network acquired from the device 104 is discriminated from the index information, the communication device address to be acquired and the terminal information to be acquired are stored in the payload areas 401 and 403 of the broadcast frame and broadcast transmission is performed. Do.

  At this time, terminal information in the network acquired from the communication device 104 is managed by the terminal information management unit 2022.

  At this time, terminal information may be requested from the communication device by unicast transmission.

  In step S806, the terminal information management unit 2022 of the second communication apparatus 102 that has received the broadcast frame transmits the requested terminal information to the second communication apparatus 103 because the address of the local station exists in the payload area 401. To do.

  Through the above process, terminal information in the network can be efficiently acquired by reusing the previous result without collecting all terminal information in the network.

  By using the present invention, it is possible to easily realize networking of AV equipment or the like incorporating a network bridge or communication device corresponding to UPnP (Universal Plug & Play) in power line communication.

Network configuration diagram in Embodiment 1 of the present invention Diagram showing the outline of the communication device Diagram showing terminal device information acquisition (broadcast) operation Diagram showing broadcast frame configuration Diagram showing the structure of index information Diagram showing the configuration of terminal device information Diagram showing terminal information acquisition (unicast) operation Diagram showing operation of terminal information (difference acquisition)

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 1st communication apparatus 102 2nd communication apparatus 103 2nd communication apparatus 104 2nd communication apparatus 105 Network equipment 106 Network equipment 107 Network equipment 108 Network equipment 109 Network equipment 110 Network equipment

Claims (6)

A plurality of communication devices are connected via a network, each communication device manages at least one network device, and performs communication between the network devices via the network,
Index information acquisition means for acquiring index information indicating information of the communication device existing in the network;
Terminal information management means for managing information on the network device managed by the device itself (hereinafter referred to as terminal information) and transmitting the terminal information to the other communication devices;
Terminal information acquisition means for acquiring the terminal information from the other communication device,
The terminal information acquisition means performs broadcast transmission including a return request for the terminal information to the other communication device, and the communication device that has not returned the terminal information based on the index information. A communication device that performs unicast communication including a request for returning terminal information. The communication apparatus according to claim 1, further comprising index information management means for managing the index information and notifying the index information in response to a request from the index information acquisition means. The terminal information acquisition means performs unicast communication using the communication parameter when the communication parameter is known in the communication device in which the terminal information has not been returned, and broadcasts when the communication parameter is not known. The communication apparatus according to claim 1, wherein communication including a return request for the terminal information is performed using communication. The broadcast transmission frame includes an address on the network of at least one of the communication devices that needs to return the terminal information;
The communication apparatus according to claim 1, wherein the terminal information management unit returns the terminal information only when the address of the communication apparatus on the network is included in the frame. The broadcast transmission frame includes an attribute of the terminal information that needs to be returned,
The communication apparatus according to claim 1, wherein the terminal information management unit returns the terminal information having an attribute described in the frame. When the terminal information of the communication device is updated, the terminal information management means notifies the index information management means of update information indicating that the terminal information has been updated, and the terminal information acquisition means If it is within the valid time based on the update information, the latest terminal information is acquired by acquiring the updated terminal information and the terminal information collected by the other or the own communication device last time. The communication device according to claim 1 or 2.

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