JP4632946B2 - Communication simulation method and communication network using the same - Google Patents

Description

  The present invention relates to a method for simulating a change in a communication state of an ad hoc network according to a movement plan of the network device when an ad hoc network is constructed using a movable network device, and the use of the method. Related to the communications network.

In recent years, for example, an ad hoc network using a movable network device such as a mobile wireless router has been studied for practical use. An ad hoc network refers to a network that is temporarily built. Examples of the features of this ad hoc network include the following.
(1) It is not necessary to set network devices in advance (you do not need to know the existence of other network devices)
(2) Network configuration autonomously (3) There is a dynamic change in the network topology such as connection / disconnection of a new network device The ad hoc network having the features as described above is a mobile communication network such as a mobile phone, In areas such as remote islands and mountainous areas where IP (Internet Protocol) network infrastructure is not established, or in places where it is not possible to connect to mobile communication networks or IP networks such as civil engineering development projects or emergency disasters Expected as a network. In addition to the applications described above, the ad hoc network is also expected to be used in a wide range of applications such as temporary networks at event venues and mobile networks in which the network itself moves by mounting network devices on-board. . The expectation for such an ad hoc network is, for example, that communication networks have become an indispensable infrastructure for exchanging e-mails and on-site photos, and in recent years for voice communication using VoIP (Voice over IP). Because.

  Of the features of the ad hoc network described above, the item shown in (3) is premised on the movement of the network device constituting the ad hoc network. Therefore, in order to construct a communication network in a wide range, it is necessary to intersperse many facilities. For this reason, it is desirable to perform an installation simulation in advance when constructing an ad hoc network so that the minimum amount of equipment is required.

Conventionally, as a method for managing communication of a moving network device, information such as a position and a radio wave condition is received from a moving mobile wireless router, and an access point (mobile router) of an appropriate backbone IP network is used based on the information. There is something to select (see, for example, Patent Document 1).
In addition, a service area test system that can efficiently perform service area measurement, optimization, management, and the like of a newly installed base station has been proposed (see, for example, Patent Document 2). This service area test system predicts a service area from a simulation result performed in advance, measures the received electric field strength, bit error rate (BER), etc. while the area measuring device moves in the predicted service area, and uses the measured data as the measurement data. The data is sent to the server, and the measurement data is analyzed in the server. Then, the analysis result is returned to the area measuring apparatus, and the mobile communication system is remotely controlled based on the return information to adjust the parameters of the newly installed base station, the antenna tilt, and the like. This makes it possible to efficiently perform service area measurement, optimization, management, and the like of the newly installed base station.

Furthermore, as a method for simulating a mobile communication network, a technique for comprehensively evaluating alternatives of the system configuration in accordance with regional conditions has been proposed. (For example, refer to Patent Document 3). This simulation method can comprehensively evaluate system configuration alternatives by predicting service quality such as call loss rate for the mobile communication network and simultaneously calculating the network cost necessary to realize the mobile communication network system. Like that. In addition, considering the geographical conditions such as the location of the radio base station and the installation status of buildings and the traffic conditions depending on the location as the input conditions for the simulation, the system configuration of the mobile communication network in the actual area can be comprehensively and accurately determined. Enable evaluation. Specifically, in a mobile communication system, using object-oriented technology, describing the elements that make up the system as objects, and simulating changes in the state of the elements on the computer, service quality such as call loss rate at the radio base station In addition, the mobile communication system is comprehensively evaluated by simultaneously calculating the network cost necessary for realizing the system configuration and realizing the system configuration.
JP 2004-120322 A JP 2004-8498 A JP-A-7-283778

  By the way, when the ad hoc network as described above is realized, it is desired to know in advance when and where the autonomously formed mobile network is configured, that is, how the communication state changes. There is a case. For example, when an enterprise (enterprise) tries to operate an ad hoc network effectively, how many network devices such as a mobile wireless router should be prepared, and what kind of route is taken as a movement route of the network device. This is because it is effective and conscious of how much costs such as labor costs and equipment costs are necessary.

  However, in the conventional technology described above, several points are provided from the start point to the end point of the movement of the network device and the situation at that point is simulated. However, since there are a plurality of moving network devices, the simulation is performed. In order to increase the accuracy, it is necessary to increase the number of points, and there is a problem that a very large number of man-hours are required. In addition, when there are an unspecified number of network users, there is also a drawback that it is difficult to inform the users of simulation results (such as communication connection / disconnection time zone information).

  In order to solve the problems of the prior art as described above, the applicant inputs the movement plan to the communication simulation apparatus when the movement plan of the network apparatus constituting the network is known in advance. Based on the information, it simulates a change in the communication state of the network that moves over time, and transmits the simulation result to a network device such as a mobile wireless router to other communication devices connected to the network device. Have proposed a technology for notifying a change prediction of a communication state based on a simulation result (for example, see Japanese Patent Application No. 2004-352754).

  However, the above-mentioned prior application invention is based on the premise that the network device moves as planned, and if the movement plan when the simulation is executed differs from the actual movement of the network device, the actual movement will be changed. It is necessary to re-input the corresponding movement plan and restart the simulation, and to retransmit the prediction information of the communication state change based on the re-simulation result to the network device. In other words, in order to notify other communication devices connected to the network device of a more accurate prediction of the change in the communication state, it is necessary to grasp the movement status of the network device or move it by a person such as a simulation administrator. There remains a problem that processing such as re-input of plan information and execution of re-simulation must be performed.

  The present invention has been made paying attention to the above points, and even when the network devices constituting the ad hoc network are not moving as planned, a re-simulation is executed without human intervention and a highly accurate communication state is achieved. It is an object of the present invention to provide a communication simulation method capable of notifying a user of a change prediction of a change and a communication network using the same.

  In order to achieve the above object, a communication simulation method of the present invention is a method for simulating a change in a communication environment associated with movement of a network device, for a communication network composed of a plurality of movable network devices, First, for each of the network devices, at least information regarding a communicable distance, position information for specifying a travel route, travel plan information regarding a travel state on the travel route, and each network device according to the travel plan The position information of the check point for determining whether or not it is moving is input. Next, based on the input information, creating simulation result information that simulates a change in communication state between each network device due to movement of each network device on a movement route, and each network device The predicted arrival time information predicting the time to reach the checkpoint is created, and the created simulation result information and predicted arrival time information are respectively transmitted to the corresponding network devices. Then, each network device that has received the transmission information detects the current location of the device itself, and obtains a difference between the time when the current location reaches the vicinity of the checkpoint and the predicted arrival time at the checkpoint. When the difference is equal to or longer than the preset allowable error time, a re-simulation request including the position information of the checkpoint and the actual arrival time is transmitted. Next, in response to the re-simulation request transmitted from each network device, the previously created simulation result information and arrival prediction time information are updated, and the updated simulation result information and arrival prediction time information are associated. It transmits to the said network apparatus, respectively.

  The communication network of the present invention is a communication network comprising a plurality of movable network devices and a communication simulation device that simulates a change in the communication environment accompanying the movement of the network device, the communication simulation device For each of the network devices, at least information regarding a communicable distance, position information for specifying a travel route, travel plan information regarding a travel state on the travel route, and each network device according to the travel plan An input unit for inputting position information of a checkpoint for determining whether or not the mobile unit is moving, and each network associated with the movement of each network device on the moving route based on the information input by the input unit Simulation of changes in communication status between devices Simulation management means for creating simulation result information and creating predicted arrival time information for predicting the time at which each network device arrives at the checkpoint; simulation result information and arrival prediction created by the simulation management means Transmitting means for transmitting time information to the corresponding network device, and instructing the simulation managing means to update simulation result information and predicted arrival time information in response to a re-simulation request transmitted from each network device. And re-simulation management means for instructing the transmission means to transmit updated simulation result information and predicted arrival time information. In addition, each of the network devices receives the simulation result information and the predicted arrival time information transmitted from the communication simulation device, and the communication of its own device based on the simulation result information received by the reception unit. Detected by the position detection unit based on notification means for notifying other communication devices connected to the own device of the state change prediction, a position detection unit for detecting the current position of the own device, and reception information of the reception unit. The difference between the time when the current position reaches the vicinity of the checkpoint and the predicted arrival time at the checkpoint is obtained, and when the difference is equal to or longer than the preset allowable error time, the position information of the checkpoint and the actual Re-simulation determination means for outputting a re-simulation request including the arrival time; Configured to re-simulation request outputted from the simulation determination means and a transmission means for transmitting to the communication simulation apparatus.

  In the communication simulation method and the communication network as described above, in addition to the simulation of the change in the communication state accompanying the movement of each network device, it is determined whether or not each network device is moving as planned. Checkpoints to be performed are input and set on the travel route, and predicted arrival time information for the checkpoints is created. Then, predicted arrival time information at the check point is transmitted to each network device together with the simulation result information of the communication state. Each network device autonomously determines whether it is moving as planned based on information from the communication simulation device, and the difference between the actual arrival time and the estimated arrival time at the checkpoint is an error. When the allowable time is exceeded, a re-simulation request is transmitted to the communication simulation apparatus. In the communication simulation device that has received the re-simulation request from the network device, the simulation result information and the predicted arrival time information are updated according to the actual movement status, and the updated information is retransmitted to each network device. It becomes like this.

  As described above, according to the present invention, each network device autonomously checks each movement status, and when an error with respect to the movement plan increases, a re-simulation is automatically executed and the result is transmitted to each network device. As a result, even when each network device does not move as originally planned, it is possible to notify the network user of a highly accurate prediction of a change in the communication state without human intervention.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. Note that the same reference numerals denote the same or corresponding parts throughout the drawings.
First, since it is useful for understanding the present invention, the communication simulation method disclosed in Japanese Patent Application No. 2004-352754 of the prior application will be outlined.
FIG. 24 is a functional block diagram showing a configuration of a communication network using a communication simulation according to the prior invention.

  The communication network shown in FIG. 24 includes a communication simulation device 2, a plurality of mobile wireless routers 5, and an IP device 7. The communication simulation apparatus 2 includes a simulation display unit 21, a simulation management unit 22, a router fixed information input unit 23, a router information management unit 24, a router movement plan information input unit 25, a simulation result information storage unit 26, and a router fixed information storage. Unit 27, router movement plan information storage unit 28, router location information storage unit 29, simulation information communication unit 31, router simulation information storage unit 32, and notification information definition information storage unit 33.

  Here, the router fixed information input unit 23 inputs registration of a mobile wireless router (hereinafter also simply referred to as “router”) 5 as a network device constituting the ad hoc network, and fixed information regarding the mobile wireless router 5. It has the function for. The fixed information input from the router fixed information input unit 23 includes, for example, a router identifier, a radio wave reachable distance (communicable distance), and other attributes related to the router (such as a router name).

  The router movement plan information input unit 25 has a function for inputting information (router movement plan information) about where and where the mobile wireless router 5 moves through which route. . The router movement plan information input from the router movement plan information input unit 25 includes, for example, information relating to a router identifier, movement start time, movement speed, and movement route. The movement route is specified (defined) by a set of position information input by the router movement plan information input unit 25.

  Based on the input information received from the router fixed information input unit 23 and the router movement plan information input unit 25, the router information management unit 24, for example, the router fixed information as shown in FIG. 25 and the router movement as shown in FIG. It has a function to create plan information. The router fixed information is stored in the router fixed information storage unit 27, and the router movement plan information is stored in the router movement plan information storage unit 28.

  Based on the simulation result from the simulation management unit 22, the simulation display unit 21 changes the movement status of the plurality of mobile wireless routers 5 and the communication state (communication availability) between the mobile wireless routers (that is, communication associated with the movement of the ad hoc network) It has a function of displaying (animation display) of changes in environment) over time. The simulation display unit 21 also has a function of receiving a simulation execution trigger from the simulation manager 1. Here, the simulation display unit 21 functions as a presentation unit.

  The simulation management unit 22 has a function of creating router location information as shown in FIG. 27 based on the router movement plan information acquired via the router information management unit 24, for example. This router location information is a set of location information for each fixed time from the movement start time of the mobile wireless router 5 and is stored in the router location information storage unit 29. The simulation management unit 22 also has a function of creating simulation result information based on router location information and router fixed information acquired via the router information management unit 24. There are as many simulation result information as the number of router identifiers (that is, the number of registered mobile wireless routers 5). For example, as shown in FIG. 28, the simulation result information includes information on time, position, and communicable router identifier. The result is stored in the simulation result information storage unit 26.

The various storage units 26 to 29 can be configured by a required recording medium such as a hard disk or a RAM, and may be configured by individual recording media, or a single or a plurality of recording media. The area may be divided and used according to information to be stored.
The simulation information communication unit 31 has a function of creating simulation information for routers (for all routers) based on the simulation result information acquired via the simulation management unit 22. In addition, the simulation information communication unit 31 creates simulation information for the router (for the own router) corresponding to each router identifier from the created router simulation information (for all routers), and the mobile wireless router 5 having each router identifier. It also has a function to transmit to each.

  For example, as shown in FIG. 29, the mobile wireless router 5 notifies the IP device 7 of the above-described router simulation information (for all routers) at the time registered in the simulation result information for each router identifier of all routers. Information (type Z1, type Z2, type Z3, etc.) to be stored and stored in the router simulation information (for all routers) storage unit 32. Further, the simulation information for the router (for the own router) is information that the own router notifies to the connected IP device 7 at the time registered in the simulation result information (for example, as shown in FIG. 30). Type Z1, type Z2, type Z3, etc.), and is stored in a simulation information storage unit 53 (to be described later) in the mobile wireless router 5.

The notification information definition information storage unit 33 stores information (notification information definition information) defining what kind of notification the mobile wireless router 5 makes to the IP device 7 and when.
Each mobile wireless router 5 includes, for example, a router body 51, a communication availability notification determination unit 52, and a simulation information storage unit 53. Each mobile wireless router 5 is connected to a communication device (IP device) 7 capable of IP communication such as a PC or PDA by wire or wirelessly.

  The router main body 51 is a main body of a general mobile wireless router, has a known function such as a wireless communication function and a Web server, and is transmitted from the simulation information communication unit 31 of the communication simulation apparatus 2 by the wireless communication function. Simulation result information can be received. Further, the function as a Web server may notify the IP device 7 connected to the own router of the prediction of the change in the communication state (disconnection, restoration, etc.) of the own router based on the received simulation result information. It can be done. In other words, the router main unit 51 connects to itself a predicted change in communication state based on a function as a receiving unit that receives a simulation result in the communication simulation apparatus 2 and a simulation result received by the receiving unit. It functions as a notification means for notifying other IP devices 7 that are currently operating.

The communication availability notification determination unit 52 periodically refers to the simulation information for the router (for the own router) stored in the simulation information storage unit 53, determines whether the notification information is described at the time, and describes If so, it has a function of notifying all the IP devices 7 connected to the own router via the router main body 51 of the notification according to the description.
Next, operations (processing flow) of the communication simulation device 2, the mobile wireless router 5, and the IP device 7 having the above-described configuration will be described.

First, when the simulation manager 1 inputs fixed information related to each mobile wireless router 5 from the router fixed information input unit 23, the router information management unit 24 uses the fixed information that has been input to obtain the router fixed information (see FIG. 25). create.
Next, when the simulation manager 1 inputs the movement plan information of each mobile wireless router 5 from the router movement plan information input unit 25, the router information management unit 24 uses the input information to make the router movement plan information (see FIG. 26). ).

  When the simulation display unit 21 receives a simulation execution request from the simulation manager 1, the simulation management unit 22 is notified to that effect. The simulation management unit 22 acquires router movement plan information via the router information management unit 24, and creates the above-described router position information (see FIG. 27) based on the router movement plan information. That is, the simulation management unit 22 creates the router position information by calculating the position where each router identifier exists after the elapse of a predetermined time from the movement start time from the information regarding the moving speed and the position set information.

  When the creation of the router location information is completed, the simulation management unit 22 next creates simulation result information (see FIG. 28). Specifically, in the example of FIG. 28, the position of each router identifier at a certain time T1, T2, T3 from the simulation start time designated by the simulation manager 1 (router identifier 1 is position A1, A2, A3, router identifier 2 calculates positions B1, B2, B3,..., And creates simulation result information, which is stored in the simulation result information storage unit 26.

  Next, the simulation management unit 22 acquires the radio wave reach distance corresponding to the router identifier from the router fixed information storage unit 27 via the router information management unit 24, and the router identifier of the router identifier at each time from the router location information storage unit 29. Other routers (communicable routers) located in the radio wave reachable range are detected, and their identifiers (communication capable router identifiers) are written in simulation result information (see identifiers X1, Y1, etc. in FIG. 28). That is, the simulation management unit 22 determines whether or not communication between routers on the travel route is possible based on information (radio wave arrival distance information and position information that identifies the travel route) input by the input units 23 and 25. It has a function.

  When the creation of the simulation result information is completed, the simulation management unit 22 passes the simulation result information to the simulation display unit 21, and the simulation display unit 21 displays the passed result to the simulation manager 1. At this time, the router fixed information can be acquired from the router fixed information storage unit 27 via the router information management unit 24 and can be simultaneously displayed as the accompanying information.

Next, when the simulation manager 1 gives a simulation data transmission request to the simulation information communication unit 31 of the communication simulation device 2, the simulation information communication unit 31 reads the simulation result from the simulation result information storage unit 26 via the simulation management unit 22. Get information.
Then, based on the notification information definition information recorded in the notification information definition information storage unit 33, the simulation information communication unit 31 creates simulation information (see FIG. 29) for each router corresponding to each mobile wireless router 5, The created information is transmitted to each mobile wireless router 5. At this time, the information transmitted to each mobile wireless router 5 is only information to which the corresponding router identifier is assigned among the simulation information for routers (for all routers).

  When each mobile wireless router 5 receives information from the communication simulation device 2, it passes the received information to the communication availability notification determination unit 52 via the router body 51. The communication availability notification determination unit 52 stores the received information in the simulation information storage unit 53 as simulation information for the own router (see FIG. 30). In addition, the communication availability notification determination unit 52 periodically refers to the simulation information for the own router stored in the simulation information storage unit 53, and if there is a description in the communication type at the referenced time, the notification according to the description (Information on communication availability) is performed to the IP device 7 via the router main body 51.

  As described above, according to the communication network to which the communication simulation method according to the prior application is applied, the information (position information) regarding the movement plan (movement route, movement start time, etc.) of each mobile wireless router 5 and the radio wave arrival distance information , The mobile wireless router 5 forms a network while moving with time, and the change in communication state follows, that is, the ad hoc accompanying the movement of each mobile wireless router 5 Changes in the network communication environment can be predicted. Therefore, since it is possible to grasp (predict) the communication state before actually moving each mobile wireless router 5 locally to construct an ad hoc network, it is not necessary to investigate a point where communication is possible locally. Since the time required for evaluation can be greatly reduced, labor costs and equipment costs can be reduced. In addition, even a user who does not know the simulation result in advance can connect the IP device 7 to the ad hoc network (mobile wireless router 5) to predict a change in the communication state of the ad hoc network accompanying movement. Therefore, work using the ad hoc network can be performed systematically.

  However, as described above, the communication simulation technique according to the invention of the prior application is based on the premise that each mobile wireless router 5 moves according to the movement plan. Therefore, if the movement plan when the simulation is executed and the actual movement of the mobile wireless router 5 are different, the simulation manager 1 re-executes the movement plan corresponding to the actual movement from the router movement plan information input unit 25. It is necessary to input and restart the simulation, and to retransmit the prediction information of the communication state change based on the re-simulation result to each mobile wireless router 5. That is, in order to notify the IP device 7 connected to each mobile wireless router 5 of a more accurate prediction of a change in the communication state, the simulation manager 1 grasps the movement status of each mobile wireless router 5. In addition, there is a problem that processing such as re-input of movement plan information and execution of re-simulation must be performed.

  Therefore, the present invention provides information necessary for each mobile wireless router to autonomously determine whether or not each mobile wireless router is moving according to the simulation according to the movement plan for the above-described communication network of the prior invention. The communication simulation apparatus creates and transmits the request, receives a re-simulation request from each mobile wireless router, adds a function of correcting the movement plan and performing the re-simulation, thereby solving the above problem.

Hereinafter, a communication network to which the communication simulation method according to the present invention is applied will be described in detail.
FIG. 1 is a functional block diagram showing the configuration of an embodiment of a communication network according to the present invention.
In FIG. 1, the communication simulation device 2 ′ constituting the communication network of the present embodiment has a checkpoint arrival time management unit 22A, a checkpoint information management unit 24A, and a configuration of the communication simulation device 2 shown in FIG. The functional blocks of the router information update unit 24B, the checkpoint information input unit 25A, the checkpoint arrival time information transmission unit 31A, the checkpoint information storage unit 34, the checkpoint arrival time information storage unit 35, and the re-simulation management unit 36 Have been added. The other functional blocks of the communication simulation apparatus 2 ′ other than those described above are the same as those of the communication simulation apparatus 2 described above.

First, the checkpoint information input unit 25A is an additional function of the router movement plan input unit 25 so that an arbitrary point on the movement route input from the router movement plan input unit 25 can be defined as a checkpoint by the simulation manager 1. It has a function to make.
The checkpoint information management unit 24A is an additional function of the router information management unit 24, and creates checkpoint information as shown in FIG. 2, for example, based on the checkpoint input by the checkpoint information input unit 25A. It has a function. The checkpoint information is configured to include location information serving as checkpoints corresponding to the identifiers of the mobile wireless routers 5 ′ constituting the ad hoc network, and is stored in the checkpoint information storage unit 34. Specifically, in the example of FIG. 2, positions o1, o2,..., Ol for router identifier 1, positions p1, p2,..., Pl for router identifier 2, and positions q1, q2,. It is set as checkpoint information.

The router information update unit 24B is an additional function of the router information management unit 24, and has a function of updating router movement plan information and checkpoint information in response to an instruction from the re-simulation management unit 36.
The checkpoint arrival time management unit 22A is an additional function of the simulation management unit 22, and based on the router movement plan information and checkpoint information acquired via the router information management unit 24, for example, a checkpoint as shown in FIG. It has a function of creating arrival time information (for all routers). The check point arrival time information (for all routers) is configured to include the check point position, the predicted arrival time, the allowable error time, and the allowable error range corresponding to the identifier of each mobile wireless router 5 ′. It is stored in the time storage unit 35. The error tolerance time and the error tolerance range are system-specific values defined in the communication simulation apparatus. The error tolerance time is the arrival time at the checkpoint calculated by the simulation, the mobile wireless router 5 ′. Is the time allowed as an error in the time when the checkpoint is actually reached. Further, the error tolerance range is a range (what hour and minute) allowed as an error between the position (latitude and longitude) of the check point calculated by the simulation and the position (latitude and longitude) actually reached by the mobile wireless router 5 ′. How many seconds). Specifically, in the example of the checkpoint arrival time information shown in FIG. 2, for the router identifier 1, arrival prediction times at the checkpoints at positions o1, o2,... Ol are a1, a2,. The time is a, the error tolerance is set to latitude x, longitude y, and for the router identifier 2, the predicted arrival times of the check points at positions p1, p2,..., Pl are b1, b2,. The allowable error time is set to a, and the allowable error range is set to latitude x and longitude y.

The checkpoint information transmission unit 31A is an additional function of the simulation information communication unit 31, and divides the checkpoint arrival time information (for all routers) acquired via the checkpoint arrival time management unit 22A for each router identifier. It has a function to transmit to the mobile radio router 5 ′.
The re-simulation management unit 36 receives a re-simulation request to be described later from each mobile wireless router 5 ′, requests the router information update unit 24B to update the router movement plan information and the checkpoint information, and the simulation management unit. A function for transmitting a re-simulation execution and checkpoint arrival time information update instruction to 22 and transmission of updated simulation information and predicted arrival time information to the simulation information communication unit 31 and the checkpoint information transmission unit 31A. It has a function to instruct.

The checkpoint information storage unit 34 and the checkpoint arrival time information storage unit 35 can be configured by a required storage medium such as a hard disk or a RAM, and may be configured by individual storage media, A storage area of a single storage medium or a plurality of storage media may be divided according to information to be stored and shared with other storage units.
For each mobile radio router 5 ′, for example, as shown in FIG. 4, the re-simulation determination unit 54, the checkpoint arrival time information storage unit 55, and the current position detection unit in the configuration of the prior invention shown in FIG. 56 functional blocks are added. The other functional blocks of each mobile radio router 5 ′ other than those described above are the same as in the case of the above-mentioned prior application invention, and thus description thereof is omitted here.

  The re-simulation determination unit 54 has a function of receiving the check point arrival time information for the own router transmitted from the check point arrival time information transmission unit 31 </ b> A of the communication simulation apparatus 2 ′ via the router body 51. As shown in FIG. 5, for example, the checkpoint arrival time information for the own router includes a router identifier, position information, predicted arrival time, error tolerance time, and error tolerance range, and a checkpoint arrival time information storage unit 55. Saved in.

  In addition, the re-simulation determination unit 54 periodically acquires its own position information from the position detection unit 56 using a satellite positioning system (GPS) provided in the mobile wireless router 5 ′, It has a function to determine whether or not the checkpoint error tolerance range described in the checkpoint arrival time information for the router has been reached. Further, the re-simulation determination unit 54 compares the predicted arrival time described in the check point arrival time information with the actual arrival time when the error reaches within the checkpoint error allowable range, and checks the difference. When the error allowable time described in the point arrival time information is exceeded, the router has a function of transmitting a re-simulation request to the re-simulation management unit 36 of the communication simulation device 2 ′ via the router body 51. The information attached to the re-simulation request transmitted to the re-simulation management unit 36 includes a router identifier, check point position information, and arrival time, as shown in FIG. 6, for example.

  The simulation information storage unit 53 and the checkpoint arrival time information storage unit 55 provided in each mobile wireless router 5 ′ can be configured by a required storage medium such as a hard disk or a RAM, and each is configured by an individual storage medium. Alternatively, the storage area of a single or a plurality of storage media may be divided and used according to information to be stored.

Next, operations (processing flow) of the communication simulation device 2 ′, the mobile wireless router 5 ′, and the IP device 7 having the above-described configuration will be described.
First, the communication simulation device 2 ′ performs router fixed information (see FIG. 25) and router movement plan information (see FIG. 26) based on the input information from the simulation manager 1 in the same manner as the processing in the communication simulation device 2 described above. ). When the creation of the router movement plan information is completed, the simulation manager 1 inputs checkpoint information of each mobile radio router 5 ′ from the checkpoint information input unit 25A. In the communication simulation apparatus 2 ′, the checkpoint information management unit 24A creates checkpoint information (see FIG. 2) based on the input information.

  Next, the communication simulation device 2 ′, like the processing in the communication simulation device 2 described above, uses the router location information (see FIG. 5) based on the router movement plan information acquired by the simulation management unit 22 via the router information management unit 24. 27). When the creation of the router location information is completed, the checkpoint arrival time management unit 22A acquires checkpoint information via the router information management unit 24, and checkpoint arrival time information for all routers based on the checkpoint information. (See FIG. 3).

  Next, the communication simulation apparatus 2 ′ performs the simulation result based on the router location information and the router fixed information acquired via the router information management section 24 in the same manner as the processing in the communication simulation apparatus 2 described above. Information (see FIG. 28) is created, and the simulation display unit 21 displays the simulation result. Then, when the simulation manager 1 gives a simulation data transmission request to the communication simulation apparatus 2 ′, the simulation information communication unit 31 creates simulation information for routers for all routers (see FIG. 29), and each mobile wireless router The corresponding simulation information is transmitted to 5 ′.

  When the transmission of the simulation information to each mobile wireless router 5 ′ is completed, the checkpoint arrival time information transmission unit 31A transmits the checkpoint arrival time information (stored in the checkpoint arrival time information storage unit 35 via the simulation management unit 22). Get all routers). Then, the checkpoint arrival time information transmission unit 31A transmits the checkpoint arrival time information corresponding to each mobile wireless router 5 '. At this time, the information transmitted from the checkpoint arrival time information transmitting unit 31A to each mobile wireless router 5 ′ is the information of the mobile wireless router 5 ′ that is the transmission destination in the checkpoint arrival time information (for all routers). Only the information to which the router identifier is assigned.

  Each mobile radio router 5 ′ receives the simulation information for its own router (see FIG. 30) transmitted from the communication simulation device 2 ′ in the same manner as the processing in each mobile radio router 5 in the above-mentioned prior invention. Then, it is stored in the simulation information storage unit 53. When the storage of the simulation information for the own router is completed, each mobile wireless router 5 ′ receives the checkpoint arrival time information from the communication simulation device 2 ′, and re-simulates the received information via the router body 51. To part 54. The re-simulation determination unit 54 stores the information passed through the router body 51 in the check point arrival time information storage unit 55 as check point arrival time information (see FIG. 5) for the own router. Then, the re-simulation determination unit 54 determines whether re-simulation is necessary, for example, according to the procedure shown in the flowchart of FIG.

  First, in step 1 (indicated by S1 in the figure, the same shall apply hereinafter), the re-simulation determination unit 54 acquires its current position by the position detection unit 56. In step 2, the stored information in the checkpoint arrival time information storage unit 55 is referred to, and the checkpoint position information and the error tolerance range described in the checkpoint arrival time information for the own router are acquired.

Next, in step 3, it is determined whether or not the current position acquired in step 1 has reached the error allowable range for the position information of the checkpoint acquired in step 2. If the current position has reached the allowable error range of the checkpoint, the process proceeds to step 4; otherwise, the re-simulation determination process is terminated.
In step 4, the re-simulation determination unit 54 acquires the current time. In step 5, the predicted arrival time and the allowable error time described in the checkpoint arrival time information for the own router are acquired with reference to the stored information in the checkpoint arrival time information storage unit 55.

In step 6, the current time acquired in step 4 and the predicted arrival time acquired in step 5 are compared, and it is determined whether or not the difference is equal to or greater than the allowable error time. If the difference is equal to or longer than the allowable error time, the process proceeds to step 7. If the difference is less than the allowable error time, the re-simulation determination process is terminated.
In step 7, the re-simulation determination unit 54 sends a re-simulation request (see FIG. 6) indicating the router identifier, the position information of the check point where the difference is equal to or greater than the error allowable time, and the actual arrival time (see FIG. 6). 51 to the re-simulation management unit 36 of the communication simulation apparatus 2 ′, and the re-simulation determination process is terminated.

Note that the timing for performing the re-simulation determination by the series of processes of Step 1 to Step 7 described above can be arbitrarily set. For example, the timing may be set every fixed time or every fixed distance.
When the re-simulation request from the mobile wireless router 5 ′ is received by the re-simulation management unit 36 as described above, the re-simulation management unit 36 moves the router to the router information update unit 24B of the router information management unit 24. Request update of plan information and checkpoint information. The router information updating unit 24B, based on the router identifier and checkpoint position information indicated in the re-simulation request passed from the re-simulation management unit 36, stores the router movement plan information stored in the router movement plan information storage unit 28. With respect to (see FIG. 26), the position information from the head position information of the travel route to which the router identifier is assigned to the same position information as the check point position information is deleted. As a result, the head position of the movement route becomes a check point where a difference equal to or greater than the allowable error time has occurred.

  Next, the router information updating unit 24B is stored in the router movement plan information storage unit 28 based on the router identifier and the actual checkpoint arrival time indicated in the re-simulation request delivered from the re-simulation management unit 36. Router movement plan information (with reference to FIG. 26, the movement start time assigned with the router identifier is overwritten with the checkpoint arrival time.

  Further, the router information updating unit 24B performs check point information (see FIG. 2) stored in the check point information storage unit 34 based on the router identifier and the check point position information from the re-simulation management unit 36. The information from the start position information of the checkpoint to which the router identifier is assigned to the position information of the checkpoint is deleted.

  Next, when the router movement plan information and the checkpoint information are updated by the router information update unit 24B, the re-simulation management unit 36 transmits a simulation execution request to the simulation management unit 22. The simulation management unit 22 that has received the simulation execution request creates new simulation result information on the basis of the updated router movement plan information and checkpoint information given through the router information management unit 24, and the checkpoint arrival time. The management unit 22A creates new checkpoint arrival time information (for all routers).

  When the re-creation of the simulation result information and checkpoint arrival time information (for all routers) by the simulation management unit 1-2 is completed, the re-simulation management unit 36 sends the simulation information communication unit 31 and the checkpoint arrival information transmission unit 31A. Then, the information transmission to each mobile radio router 5 ′ is requested, and the regenerated simulation information and checkpoint arrival time information are transmitted to each mobile radio router 5 ′ in the same manner as described above. As a result, each mobile wireless router 5 ′ can notify the IP device 7 connected to each mobile device of a highly accurate prediction of a change in the communication state even when the situation is different from the initial movement plan. it can.

Here, the series of processes will be described in detail with a specific example.
For example, as shown in FIG. 8, there are two vehicles (hereinafter referred to as router X and router Y) equipped with a mobile wireless router 5 ′, and IP between router X and router Y from point A to point B. Assume that there is a plan to move on separate routes R1 and R2 while communicating. Hereinafter, the simulation at that time will be described with specific numerical examples.

  First, when receiving a router registration request from the simulation manager 1, the router fixed information input unit 23 displays a router fixed information input screen. In this example, in addition to an IP address and a radio wave reach distance as a router identifier, a name (router X, router Y, etc.) is used as an input item. The input information is input to the router information management unit 24, and the router information management unit 24 creates router fixed information and registers it in the router fixed information storage unit 27. An example of the registration is shown in FIG. In FIG. 9, the radio wave arrival distance of the router X having the IP address “10.4.3.206.190” is 18.0 [km] in radius, and the radio wave arrival distance of the router Y having the IP address “10.4.3206.189” is Each is registered as having a radius of 20.0 [km].

  Next, when receiving a router movement plan information input request from the simulation manager 1, the router movement plan information input unit 25 displays the registered routers and prompts the router to input a movement plan. For example, when inputting the router movement plan information for the router X, the router movement plan information input unit 25 displays a map and moves by tracing the movement route of the router X on the map by a drag operation with a mouse or the like. The route is recorded and an input screen for moving start time and moving speed is separately displayed.

  An example of the router movement plan information created in this way is shown in FIG. In FIG. 10, the router X (IP address = 10.43.206.190) moves to “2004/12/1 13:00” (year / month / day / time) at a speed of 60.0 [km] per hour. Start, position (42.59.15, 141.21.25), position (42.59.17, 141.21.16), ..., position (43.49.15, 144.6.39) It represents moving along a route R1 (latitude, longitude). The router Y (IP address = 10.43.206.189) starts moving to “2005/12/1 13:10” (year / month / day / time) at 65.0 [km] per hour. , Position (42.61.17, 141.20.16), position (42.61.20, 141.20.06), ..., position (43.49.15, 144.6.39) It represents moving along a route R2 (latitude, longitude).

  Subsequently, upon receiving a checkpoint information input request from the simulation manager 1, the checkpoint information input unit 25A displays the previously input movement route information of each router X, Y, and inputs the checkpoint information for each router. Prompt. For example, when the checkpoint information is input for the router X, the checkpoint information input unit 25A records the checkpoint information by clicking an arbitrary point on the moving route input previously with the mouse as shown in FIG. To do. An example of checkpoint information created in this way is shown in FIG. In FIG. 12, the checkpoints of the router X (IP address = 10.43.206.190) are the position (42.524.43, 142.26.22) and the position (43.15.43, 143.35. 05). Also, the checkpoints of router Y (IP address = 10.43.206.189) are position (43.45.57, 142.159), position (44.01.24, 143.30.47) It represents that it is two places.

Next, when the simulation display unit 21 receives a simulation execution request from the simulation manager 1, the simulation display unit 21 notifies the simulation management unit 22 to that effect. The simulation management unit 22 notifies the router information management unit 24 of the router movement plan information request, and acquires the router movement plan information from the router information management unit 24.
The simulation management unit 22 creates router location information from the acquired router movement plan information. In this example, the simulation start time and the step of the simulation time can be notified from the simulation manager 1 when the simulation execution is requested. An example of router location information is shown in FIG. The example shown in FIG. 13 is an example when the simulation start time is notified as “2005/12/1 13:00” and the simulation time increment is notified as 10 minutes.

  When the creation of the router location information is completed, the simulation management unit 22 next notifies the router information management unit 24 of the router fixed information request, and acquires the router fixed information from the router information management unit 24. The simulation management unit 22 creates simulation result information from the radio wave arrival distance of the router fixed information and the router position information. An example of simulation result information created at this time is shown in FIG. In FIG. 14, the router identifier “10.4.3206.190” has no other router that can communicate at the time of 13:00 and 13:20, and the router identifier “10.190” at time 13:10. This indicates that the router X with 43.206.190 "can communicate with the router Y with the router identifier" 10.4.3.206.189 ". The position is represented by the latitude and longitude of each router.

  When the creation of the simulation result information is completed, the checkpoint arrival time management unit 22A next notifies the router information management unit 24 of the checkpoint information request, and acquires the checkpoint information via the router information management unit 24. Further, the checkpoint arrival time management unit 22A notifies the router information management unit 24 of the router movement plan information request, and acquires the router movement plan information from the router information management unit 24. Then, the checkpoint arrival time management unit 22A creates checkpoint arrival time information for all routers based on the acquired checkpoint information and router movement plan information. An example of checkpoint arrival time information (for all routers) created at this time is shown in FIG. In FIG. 15, the router identifier “10.4.3.206.190” arrives at checkpoints “42.52.43, 142.6.22”, “2005/12/1 16:00”, and This indicates that the checkpoint “43.15.43, 143.35.05” is scheduled to arrive at “2005/12/1 19:30”. Also, the router identifier “10.4.3.206.189” arrives at checkpoints “43.45.57, 142.21.59” and “2005/12/1 15:40”, and the next checkpoint “ 44.01.24, 143.30.47 ", indicating that it is scheduled to arrive at" 2005/12/1 18:50 ".

  When the checkpoint arrival time management unit 22A completes the creation of checkpoint arrival time information (for all routers), the checkpoint arrival time management unit 22A notifies the simulation display unit 21 via the simulation management unit 22. The simulation display unit 21 displays the simulation result information like an animation. Display examples of simulation results are shown in FIGS. Here, the routers in a communicable state are displayed so that the connection line is drawn. 16 to 18, the symbol AX indicates the radio wave arrival distance (communication area) of the router X, and the symbol AY indicates the radio wave arrival distance (communication area) of the router Y. That is, the simulation management unit 22 can also display the radio wave arrival distance corresponding to the radio wave arrival distance information on the simulation display unit 21.

  For example, as shown in FIG. 16, at time 13:00, the router X and the router Y are not within the communicable distance (not within the communicable areas AX and AY). No connection line is drawn between the two. At this time, it can be displayed together with the date and time that the communication between the router X and the router Y is impossible (see the lower right in FIG. 16). However, as shown in FIG. 17, since the router X and the router Y approach each other at a time 13:10 and are within a communicable distance, it is possible to communicate between the router X and the router Y. The connecting line C to be drawn is drawn (displayed). At this time, it can be displayed together with the date and time that the communication between the router X and the router Y is possible (see the lower right in FIG. 17). Further, as shown in FIG. 18, at time 13:20, the router X and the router Y again exceed the communicable distance, so that a connection line is drawn between the router X and the router Y. Absent. Also in this case, it can be displayed together with the date and time that the communication between the router X and the router Y is impossible (see the lower right in FIG. 18).

  In this way, the simulation result information is continuously displayed as an animation over time. That is, it is possible to confirm (predict) when and where the communication cannot be performed by displaying so that the connection line C appears and disappears between the routers X and Y as the routers X and Y move. it can. However, the display of the communicable state is not limited to such connection line display, and other display methods can also be used. Since the simulation result information is stored in the simulation result information storage unit 26, it can be reproduced any number of times, and a primary stop can be performed.

  When the display of the simulation result information is completed, the router simulation information (for all routers) is created and transmitted. Specifically, when the simulation information communication unit 31 receives a simulation information transfer request from the simulation manager 1 to the mobile wireless router 5 ′, the simulation information communication unit 31 acquires simulation result information via the simulation management unit 22. To do. Then, the simulation information communication unit 31 creates simulation information for routers (for all routers) according to the rules described in the notification information definition information as shown in FIG. 19 stored in the notification information definition information storage unit 33, for example. To do.

  An example of the router simulation information (for all routers) created at this time is shown in FIG. In FIG. 20, referring to the communicable router identifier of the date and time “2005/12/1 13:00” of the router identifier (IP address) “10.4.3206.190” of the simulation result information, the communicable router identifier is You can see that it doesn't exist. In other words, cutting. Referring to the notification information definition information, it is described as “Notify restoration when there is a communicable router after 10 minutes after disconnection”, so the communicable router identifier of date and time “2005/12/1 13:10” Since the IP address is described, the notification information is “recovered to 13:10”. Therefore, the notification information of the date and time “2005/12/1 13:00” of the router identifier “10.4.3.206.190” of the simulation information for routers (for all routers) is “recovered, 13:10”. The above processing is performed for all times and all router identifiers.

  When the creation of the simulation information for routers (for all routers) is completed, the simulation information communication unit 31 transmits, for example, only the simulation information for the router X having the IP address “10.4.3206.190” to the router X. When the router X receives the simulation information from the simulation information communication unit 31, the router X passes the information to the communication availability notification determination unit 52 via the router body 51, and the communication availability notification determination unit 52 transmits the information to the router simulation information. (Self router) is stored in the simulation information storage unit 53.

  When transmission of simulation information from the simulation information communication unit 31 to the routers X and Y is completed, the checkpoint arrival time information transmission unit 31A acquires checkpoint arrival time information (for all routers) via the simulation management unit 22. . The checkpoint arrival time information transmission unit 31A divides the acquired checkpoint arrival time information (for all routers) for each router and transmits it.

  The router X that has received the transmission information from the checkpoint arrival time information transmission unit 31A passes the information to the re-simulation determination unit 54 via the router body 51, and the re-simulation determination unit 54 transmits the information to the own router. The checkpoint arrival time information storage unit 55 stores the checkpoint arrival time information for the router. The same applies to the router Y.

Next, each of the routers X and Y notifies the IP device 7 connected to each of them based on the simulation information for the router corresponding to the own router. Specifically, the router X records the time interval of the simulation information for its own router when the information is received, and refers to the information at the time interval. For example, if the current time is “2005/12/1 13:10”, the communication availability notification determination unit 52 is described as “disconnected, 13:20” in the notification information 1, and therefore, for example, “13:20 An HTML (Hyper Text Markup Language) file that says “Communication with other routers will be cut off at about this time” is made public by a Web server. Since most routers in recent years are equipped with a Web server for maintenance, the function can be used.

  In the IP device 7, the Web browser is always activated, and the URL page of the HTML file is opened. By incorporating a script for periodically updating its own page in the HTML file, the Web browser of the IP device 7 periodically updates the URL. Therefore, even if the user of the IP device 7 changes the message, This can be known without operating the web browser. Note that it is possible to notify the IP device 7 of a predicted change in communication state using a known communication function without using a Web server and Web browser as described above.

  Next, the re-simulation determination unit 54 of each router X, Y periodically acquires its own position information from the position detection unit 56, and the position of the checkpoint described in the checkpoint arrival time information for its own router It is determined whether a point within the allowable error range has been reached. For example, the re-simulation determination unit 54 of the router X has reached the point within the allowable error range “0.1.0” from the check point “42.52.43, 142.26.22”. Determine whether. When the checkpoint “42.52.43, 142.26.22” is reached within the allowable error range, the arrival time “2005/12/1 16:00” described in the checkpoint arrival time information is the current Since the time “2005/12/1 17:00” is compared and there is a difference of 5 minutes or more which is an allowable error time, the re-simulation management unit 36 of the communication simulation apparatus 2 ′ is connected to the re-simulation management unit 36 via the router body 51. Send a re-simulation request.

In the re-simulation request transmitted at this time, for example, as shown in FIG. 21, the identifier “10.4.3206.190” of the router X and the position of the check point where the difference occurs “42.52.43, 142.26. 22 ”and the actual arrival time“ 2005/12/1 17:00 ”are given.
When receiving the re-simulation request from the router X, the re-simulation management unit 36 requests the router information update unit 24B to update the router movement plan information and the check point information via the router information management unit 24. Specifically, the router information update unit 24B receives the router identifier “10.4.3.206.190”, the checkpoint positions “42.52.43, 142.26.22”, and the like given from the re-simulation management unit 36. The router movement plan information is updated based on the arrival time “2005/12/1 17:00”. FIG. 22 shows the router movement plan information updated at this time. In the example of FIG. 22, the router information update unit 24B checks the checkpoints “42.52.43, 142.6.22” from the head of the travel route to which the router identifier “10.4.3206.190” is assigned. The position information until reaching “” is deleted, and the movement start time is overwritten with the check point arrival time “2005/12/1 17:00”.

  Further, the router information updating unit 24B is based on the router identifier “10.4.3.206.190” and the checkpoint position “42.52.43, 142.26.22” passed from the re-simulation management unit 36. Then, the checkpoint information “42.52.43, 142.26.22” is deleted from the head of the checkpoint information to which the router identifier “10.4.3206.190” of the checkpoint information is assigned. FIG. 23 shows the checkpoint information updated at this time.

  When the router movement plan information and the checkpoint information are updated by the router information updating unit 24B as described above, the re-simulation management unit 36 next transmits a re-simulation execution request to the simulation management unit 22. This re-simulation process is the same as the above-described initial simulation process, and the router X starts from the checkpoints “42.52.43, 142.26.22” to “2005/12/1 17:00”. A re-simulation is executed assuming that the movement is started in the network, and new router simulation information (for all routers) and checkpoint arrival time information (for all routers) are created and transmitted to the routers X and Y. It will be.

  As described above, according to the present embodiment, the movement status of each mobile wireless router 5 ′ (router X, Y) is autonomously detected, the movement plan information is updated, the re-simulation is executed, and the re-simulation result It is possible to automatically perform up to transmission of. Thereby, the information notification to the IP device 7 connected to each mobile wireless router 5 'is also automatically updated, and it becomes possible to notify the communication state change with higher accuracy.

It is a functional block diagram which shows the structure of one Embodiment of the communication network by this invention. It is a figure which shows an example of the checkpoint information in the communication network of FIG. It is a figure which shows an example of the checkpoint arrival time information (for all routers) in the communication network of FIG. It is a functional block diagram which shows the structural example of the mobile wireless router used for the communication network of FIG. It is a figure which shows an example of the checkpoint arrival time information (for own router) in the communication network of FIG. It is a figure which shows an example of the re-simulation request | requirement in the communication network of FIG. It is a flowchart which shows the procedure of the re-simulation determination performed in each mobile wireless router in the communication network of FIG. It is a figure which shows an example of the movement route | root of each router assumed as a specific example of the communication network of FIG. It is a figure which shows an example of the router fixed information in the specific example of FIG. It is a figure which shows an example of the router movement plan information in the specific example of FIG. FIG. 9 is a diagram for describing an input operation of checkpoint information in the specific example of FIG. 8. It is a figure which shows an example of the checkpoint information in the specific example of FIG. It is a figure which shows an example of the router location information in the specific example of FIG. It is a figure which shows an example of the simulation result information in the specific example of FIG. It is a figure which shows an example of the checkpoint arrival time information (for all routers) in the specific example of FIG. It is a figure which shows the example of a display of the simulation result information in the specific example of FIG. It is a figure which shows the other example of a display of the simulation result information in the specific example of FIG. It is a figure which shows another example of a display of the simulation result information in the specific example of FIG. It is a figure which shows an example of the notification information definition information in the specific example of FIG. It is a figure which shows an example of the simulation information (for all routers) for routers in the specific example of FIG. It is a figure which shows an example of the re-simulation request | requirement in the specific example of FIG. It is a figure which shows an example of the router movement plan information updated in the specific example of FIG. It is a figure which shows an example of the updated checkpoint information in the specific example of FIG. It is a functional block diagram which shows the structure of the communication network using the communication simulation by prior invention. It is a figure which shows an example of the router fixed information in the communication network of FIG. It is a figure which shows an example of the router movement plan information in the communication network of FIG. It is a figure which shows an example of the router location information in the communication network of FIG. It is a figure which shows an example of the simulation result information in the communication network of FIG. It is a figure which shows an example of the simulation information (for all the routers) for routers in the communication network of FIG. It is a figure which shows an example of the simulation information (for own router) for routers in the communication network of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Simulation manager 2, 2 '... Communication simulation apparatus 5, 5' ... Mobile wireless router 7 ... IP apparatus 21 ... Simulation display part 22 ... Simulation management part 22A ... Checkpoint arrival time management part 23 ... Router fixed information input part 24 ... Router information management unit 24A ... Checkpoint information management unit 24B ... Router information update unit 25 ... Router movement plan information input unit 25A ... Checkpoint information input unit 26 ... Simulation result information storage unit 27 ... Router fixed information storage unit 28 ... Router movement plan information storage unit 29 ... Router position information storage unit 31 ... Simulation information communication unit 31A ... Check point arrival time information transmission unit 32 ... Router simulation information storage unit 33 ... Notification information definition information storage unit 34 ... Check point information storage Unit 35 ... Checkpoint arrival time information storage unit 36 ... Re-simulation management unit 51 ... Router main body unit 52 ... Communication availability notification determination unit 53 ... Simulation information storage unit 54 ... Re-simulation determination unit 55 ... Checkpoint arrival time information storage unit 56 ... Position detector

Claims (5)

A communication simulation method for simulating a change in a communication environment associated with movement of the network device for a communication network composed of a plurality of movable network devices,
For each of the network devices, at least information regarding a communicable distance, position information for specifying a travel route, travel plan information regarding a travel state on the travel route, and the network devices move according to the travel plan. Enter the location information of the checkpoint that determines whether or not
Based on the input information, it creates simulation result information that simulates a change in the communication state between the network devices as the network devices move on the movement route, and the network devices serve as the check points. Create predicted arrival time information that predicts the arrival time,
The created simulation result information and predicted arrival time information are respectively transmitted to the corresponding network devices,
In each network device that has received the transmission information, it detects the current position of its own device, finds the difference between the time when the current position reaches the vicinity of the checkpoint and the predicted arrival time of the checkpoint, When the difference is equal to or longer than the preset error tolerance time, a re-simulation request including the position information of the checkpoint and the actual arrival time is transmitted,
In response to the re-simulation request transmitted from each network device, update processing of the simulation result information and arrival prediction time information created earlier,
A communication simulation method, wherein the updated simulation result information and predicted arrival time information are respectively transmitted to the corresponding network devices. A communication network comprising a plurality of movable network devices, and a communication simulation device for simulating a change in communication environment accompanying the movement of the network devices,
The communication simulation device includes:
For each of the network devices, at least information regarding a communicable distance, position information for specifying a travel route, travel plan information regarding a travel state on the travel route, and the network devices move according to the travel plan. Input means for inputting checkpoint position information for determining whether or not
Based on the information input by the input means, it creates simulation result information that simulates a change in the communication state between the network devices accompanying the movement of the network devices on the moving route, and the network devices Simulation management means for creating predicted arrival time information that predicts the time at which the check point will be reached,
Transmitting means for transmitting the simulation result information and the predicted arrival time information created by the simulation management means to the corresponding network devices;
In response to the re-simulation request transmitted from each network device, the simulation management unit is instructed to update the simulation result information and the predicted arrival time information, and the simulation unit is updated with respect to the simulation result information and A re-simulation management means for instructing transmission of predicted arrival time information,
Each of the network devices is respectively
Receiving means for receiving simulation result information and predicted arrival time information transmitted from the communication simulation device;
Based on the simulation result information received by the receiving means, a notification means for notifying other communication devices connected to the own device of a change in the communication state of the own device, a position detecting means for detecting the current position of the own device,
Based on the reception information of the receiving means, a difference between the time when the current position detected by the position detecting means reaches the vicinity of the checkpoint and the predicted arrival time of the checkpoint is obtained, and the difference is set in advance. Re-simulation determination means for outputting a re-simulation request including the position information of the checkpoint and the actual arrival time when there is an error allowable time or more;
A communication network comprising: transmission means for transmitting a re-simulation request output from the re-simulation determination means to the communication simulation apparatus.   The communication network according to claim 2, wherein the communication simulation apparatus includes a presentation unit that presents simulation result information created by the simulation management unit to a simulation manager.   The input means includes a fixed information input unit that inputs registration and fixed information of each network device, a movement plan information input unit that inputs movement plan information of each network device registered in the fixed information input unit, The checkpoint information input unit for setting the checkpoint on the movement route indicated in the movement plan information of each network device input by the movement plan information input unit. The communication network described. Each of the network devices is a wireless router mounted on a vehicle,
The communication network according to any one of claims 2 to 4, wherein the position detection unit periodically acquires position information using a satellite-based positioning system provided in the router.

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