JP2003087310A - Routing method in communication network and communication system employing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a routing method capable of executing an appropriate routing in a communication network where communication conditions are changing while suppressing the number of communication times among devices and to provide a communication system employing the same. SOLUTION: Prior to transmission of information from an information transmitter to an information receiver, the information transmitter calculates a plurality of communication paths between the information transmitter and the information receiver on the basis of prescribed evaluation indices calculated in advance, having been set or set according to a newest communication condition, creates a routing table for each relaying device on the basis of the calculation result, and each relaying device executes relaying information on the basis of the routing table.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a routing method in a communication network that connects an information transmitting device, a plurality of relay devices, and an information receiving device, and more particularly, to the number of times of communication between devices even in an environment where communication conditions change. Suppress
The present invention relates to a routing method capable of performing proper routing and a communication system using the same.

[0002]

2. Description of the Related Art Generally, there are two types of routing (relay route setting) in a communication network: static routing and dynamic routing.
The former static routing is a method in which a user fixedly sets a communication route in advance, and is suitable when the scale of the communication network is relatively small and the user can manage the communication route.

On the other hand, the latter dynamic routing is a method in which information is exchanged between devices that relay information at any time, and an optimum communication path is set according to the situation at that time, and the scale of the communication network is relatively large. big,
This is effective in an environment where the communication status changes from time to time.
RIP (Routing Information Protocol), OSP is used as a routing control protocol for such routing.
F (Open Shortest Path First) is often used.

FIG. 10 is a diagram showing an example of the configuration of a conventional communication system. Generally, a communication system that constructs a communication network includes an information transmitting device 5 that transmits information,
It is composed of a plurality of relay devices 6 that relay the transmitted information and an information receiving device 7 that is the destination of the information, and an example of the configuration inside each of these devices is shown in the figure. As shown in the figure, each device has a communication control means (51, 61, 7).
1), storage means (52, 62, 72), communication means (5
3, 63, 73) and display / input / output means (54, 6)
4, 74) in the same manner, and the communication control means (51, 61,
71), the above-mentioned RIP, OSPF, etc. are used.

In such a conventional communication system, during routing, the communication control means of each device autonomously and regularly communicates frequently with communication control means of other devices other than itself, thereby changing the situation. Even in such an environment, the route setting that maximizes the predetermined evaluation function to the destination is established.

[0006]

However, in such a conventional routing method, as described above, it is necessary to frequently communicate between the devices, and the communication amount and the number of communications are large. Therefore, there is a possibility that it will be built in the battlefield during the war, or communication will be impaired to other radios, but in highly urgent radio communication systems and communication networks, the environment tends to change, so dynamic routing is necessary. However, in the above-mentioned method, radio waves are frequently radiated, which has an adverse effect that the device can be easily found on the other party or interferes with the other party's radio.
In such a communication system, a routing method that suppresses the number of communication between devices is desired.

Therefore, an object of the present invention is to perform proper routing in a communication network in which the communication situation changes.
A routing method and a communication system using the same that can be implemented while suppressing the number of communications between devices.

[0008]

In order to achieve the above object, according to one aspect of the present invention, before transmitting information, the information transmitting apparatus sets a plurality of priorities based on the latest communication status. Create a routing table showing the communication routes of
That is, when transmitting information, each relay device relays information based on the routing table. Therefore, according to the present invention, the number of communications can be suppressed as compared with the conventional system in which each device repeats communications with other devices at any time,
On the other hand, the routing table is created or updated with the latest information, and multiple routes with priorities are secured, so information is transmitted through an appropriate communication route even in an environment where the communication status changes. be able to.

In order to achieve the above object, another aspect of the present invention is a routing method in a communication network composed of an information transmitting device, a plurality of relay devices and an information receiving device. Before transmitting information to the information receiving device, the information transmitting device selects a plurality of communication routes from communication routes existing in the communication network based on a predetermined evaluation index and A first step of deciding a priority and transmitting information regarding the selected communication path including the priority to each of the relay devices as a routing table; and when transmitting information from the information transmitting device to the information receiving device Each of the relay devices receiving the transmission information to be transmitted, based on the transmitted routing table, Determined, and having a second step for transmitting transmission information to the received the next of the relay apparatus or the information receiving apparatus on the communication path and the determined.

Further, in a preferred aspect of the above invention, the routing table transmitted by the information transmitting device to each of the relay devices is based on information about a communication state acquired by each of the relay devices as appropriate. It is characterized in that it is updated in the transmitting device or each of the relay devices.

Further, in the above invention, another aspect is
It is characterized in that the relay device determines the communication route based on the priority order by selecting the communication route having the highest priority order from among the communication routes available at the time of the determination.

Further, in the above invention, another aspect is characterized in that the predetermined evaluation index includes communication reliability and / or survivability of each communication path.

Further, in the above invention, another aspect is
The communication reliability of each of the communication paths is obtained based on the communication reliability of each of the paths between the two devices forming the communication path.

In the above invention, another aspect is
The survivability of each of the communication paths is obtained based on the survivability of each of the relay devices on the communication path.

In the above invention, another aspect is
Further, when the receiving device that receives the transmission information returns the information to the transmitting device, the receiving device is the transmitting device in the first and second steps, and the transmitting device is the first and second transmitting devices. The receiving device in the second step is characterized by including a step of executing the first and second steps or a step of executing a reply of the information through a communication path through which the transmission information is transmitted.

Further, according to the present invention, since each relay device can limit the communication partner, the RIP (Routing)
Information Protocol), OSPF (Open Shortest Pa)
It is also possible to reduce the communication amount and communication line of dynamic routing by using it together with a dynamic routing protocol such as (th First).

In order to achieve the above-mentioned object, another aspect of the present invention is an information transmitting apparatus that is a source of information, a plurality of relay apparatuses that relay the information, and a destination of the information. A communication system having an information receiving device and constructing a communication network, wherein the information transmitting device, based on a predetermined evaluation index, transmits the information from the information transmitting device to the information receiving device. Each of the relay devices selects a plurality of communication routes from among the communication routes existing in the communication network, determines the priority of the selected communication routes, and uses information about the selected communication routes including the priority as a routing table. When transmitting information to the information receiving device from the information transmitting device, each relay device that receives the transmission information to be transmitted is transmitted to the information receiving device. The relay of the information is performed by determining a communication route based on a routing table and transmitting the received transmission information to the next relay device or information receiving device on the determined communication route. And

Further, in the above invention, in a preferred aspect thereof, the routing table transmitted by the information transmitting device to each of the relay devices is based on information about a communication state acquired by each of the relay devices as appropriate. It is characterized in that it is updated in the transmitting device or each of the relay devices.

Further, in the above invention, another aspect is
It is characterized in that the relay device determines the communication route based on the priority order by selecting the communication route having the highest priority order from among the communication routes available at the time of the determination.

In order to achieve the above-mentioned object, another aspect of the present invention is an information transmitting apparatus that transmits information to an information receiving apparatus by using a plurality of relay apparatuses. Prior to transmission, a plurality of communication routes are selected as candidates for the communication route used at the time of transmitting the information based on a predetermined evaluation index, and a priority order in using the selected communication route is determined, The information about the selected communication path including the rank is transmitted to each of the relay devices as a routing table.

Further, in a preferred aspect of the above-mentioned invention, the routing table transmitted to each of the relay devices is appropriately updated based on the information regarding the communication state transmitted from each of the relay devices. .

Further objects and features of the present invention will be apparent from the embodiments of the invention described below.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. However, such an embodiment does not limit the technical scope of the present invention.
In the drawings, the same or similar components will be described with the same reference numerals or reference symbols.

FIG. 1 is a diagram showing an example of a device configuration diagram according to an embodiment of a communication system to which the present invention is applied. As shown in the figure, the communication system 1 includes a plurality of information transmitting apparatuses 2 that are sources of information, a plurality of relay apparatuses 3 that relay transmitted information, and a plurality of information receiving apparatuses that are destinations of information. The device 4 is configured, and when transmitting information, the most suitable route is selected from a plurality of existing communication routes. In addition, in the present embodiment, it is assumed that wireless communication is used as the communication means and the environment of the communication changes from time to time. In addition, the number of each device shown in FIG.
For example, different numbers of devices may exist, and information may be transmitted from the information receiving device to the information transmitting device.

FIG. 2 shows a communication system 1 according to this embodiment.
It is a figure showing the composition in each device which constitutes. The information transmitting device 2 is composed of the respective means shown in the figure. First, the communication path network optimizing means 21 determines an optimum plurality of communication paths to each information receiving device 4 from the viewpoints of communication reliability and survivability. This is a part for creating a routing table to be selected and distributed to each relay device 3. The storage unit 22 is a unit for storing various information such as information to be transmitted and information necessary for selecting an optimal communication route in the communication route network optimizing unit 21, and the communication control unit 23 communicates. This is a part for performing control when communicating with another device via the means 24. Further, the communication unit 24 is a part that actually transmits and receives information to and from other devices, and the display / input / output unit 25 forms an interface with the operator of the information transmitting device 2, and the operator can be operated by the unit. Information is displayed on the screen and information such as the location of the device is input.

Next, the relay device 3 and the information receiving device 4 have the same structure as shown in the figure, and the storage means 31, 41.
Is a part for storing various information, and the storage means 31 of the relay device 3 stores the routing table transmitted from the information transmitting device 2. Also, the communication control means 3
Similarly to the case of the information transmission device 2, the reference numerals 2 and 42 perform control when communicating with other devices, but the communication control means 32 of the relay device 3 particularly transfers information from the information transmission device 2 to the information reception device 4. At the time of information transmission, relay of information according to the routing table is controlled. The communication means 33, 43 and the display / input / output means 34, 44 have the same functions as the corresponding parts of the information transmission device 2.

The communication system 1 according to the present embodiment having the above-mentioned configuration intends to perform proper routing by a method in which the number of times of communication between devices is suppressed as much as possible even in an environment where communication conditions change. To do.

FIG. 3 is a flow chart exemplifying the procedure of routing and information transmission based on the routing performed in the communication system 1 according to the present embodiment. First, the information transmitting device 2 and the information regarding the arrangement locations of the information receiving device 4 and the relay device 3 are input to the information transmitting device 2 (step S1 in FIG. 3). The input operation is usually performed by the operator displaying the map data previously stored in the storage means 22 on the display / input / output means 25.
On top of that, the location of the device is specified.

Next, in the communication route network optimizing means 21 of the information transmitting device 2, a place where the relay device 3 is actually arranged from the inputted placement candidate positions of the relay device 3 by a predetermined optimization method. Is determined (step S in FIG. 3)
2). It is preferable that the placement location is determined so that it is optimally placed according to the application of the communication network to be constructed. For example, in the above-mentioned battlefield communications, the reliability of the communication and the discoverability of the other party Optimization is performed by using the relay device (location) survivability and the like as an evaluation index in consideration of the device failure rate. The determined optimum placement location of the relay device 3 is the display / input / output means 2 of the information transmission device 2.
5 is output and displayed (step S3 in FIG. 3). Note that the above steps S1 to S3 do not necessarily have to be performed in the information transmitting device 2, but may be performed by an external device, and the result may be received by the information transmitting device 2.

Next, the communication route network optimizing means 21 of the information transmitting device 2 transmits the information to the information receiving device 4 based on the information such as the determined location of the relay device 3 and the like. The routing table showing the
It is created for each (step S4 in FIG. 3). Creation of such a routing table is a main part of routing in the communication system 1, and its procedure will be described below.

FIG. 4 is a diagram showing an example of a procedure for creating a routing table performed by the information transmitting device 2. First, a plurality of information receiving devices 4 that are information transmission destinations are designated (step S21 in FIG. 4). Next, the communication path network optimizing means 21 can be constructed between the information transmitting device 2 and the designated all information receiving device 4 via the plurality of relay devices 3 whose arrangement has been determined. The communication path is calculated (step S22 in FIG. 4).

Then, for each calculated communication path, the communication reliability evaluation value of the communication path is calculated (step S in FIG. 4).
23). The communication reliability evaluation value of the communication path is obtained from the communication reliability evaluation value for the path between the plurality of two devices forming the communication path. For example, the communication route from the information transmitting device 2 to the information receiving device 4 via the two relay devices 3 is composed of three routes connecting the two devices, and the communication reliability evaluation values of those routes are X1, If X2 and X3 are set, the communication reliability evaluation value of the communication path is X1 × X.
It is calculated by 2 × X3.

The communication reliability evaluation value for the route between the two devices is obtained by the following equation (1).

Communication reliability evaluation value = line-of-sight evaluation value × received radio wave strength evaluation value × bit error rate evaluation value (1) However, each item on the right side of the above equation (1) is in accordance with the evaluation value calculation method shown in FIG. It is calculated based on each. The method of obtaining the communication reliability evaluation value of the entire communication path described above by the product of the evaluation values of the respective paths, and the above formula (1) are examples.
The communication reliability evaluation value may be obtained by another formula.

Next, similarly, for each communication path, the survivability evaluation value of the communication path is calculated (step S2 in FIG. 4).
4). The survivability evaluation value is calculated from the survivability evaluation value of each of the plurality of relay devices 3 existing on the communication path by the following equation (2).

[0036]

[Equation 1]

However, f _k : the survivability evaluation value of the k-th relay device 3 in the communication path and the survivability evaluation value of each relay device 3 are obtained by the following equation (3).

Survivability evaluation value = Concealability evaluation value × Discovery evaluation value × Device failure rate evaluation value (3) However, each item on the right side of the above expression (3) is as shown in FIG.
It is obtained based on the evaluation value calculation method shown in (b) and (c). The above equations (2) and (3) are
This is an example, and the survivability evaluation value may be obtained by another formula.

When the communication reliability evaluation value and the survivability evaluation value of each communication path are calculated as described above, the communication path network optimizing means 21 then performs all communication based on those evaluation values. A communication route used for information transmission is selected from the routes. Specifically, the communication reliability evaluation value, the survivability evaluation value, and the number of relays of each communication path are compared with predetermined threshold values for each, and the communication reliability evaluation value and the survivability evaluation value are respectively If the number of relays is greater than the threshold value and the number of relays is less than the threshold value, the communication path is selected (steps S25, S26, and S27 in FIG. 4).

On the other hand, if not, the communication path is not selected and is deleted (step S28 in FIG. 4).
Note that the number of relays means the information transmitting device 2 to the information receiving device 4
It is the number including the information receiving device 4 of the device that is relayed up to the above. For example, when passing through two relay devices 3, the number of relays is three. Further, in the present embodiment, the above three indexes are used for selecting an appropriate communication path. However, depending on the communication network to be constructed, it is possible to select a communication path using different indexes depending on its application. it can.

Next, the communication route network optimizing means 21 will not be able to secure an alternative communication route if any one of the relay devices 3 in the selected communication route group fails. Check whether or not. As a result of the check, if the alternative communication path cannot be secured, the selection of the communication path is redone by changing the threshold value or the like so that the alternative communication path can be secured (FIG. 4).
Step S29). This is because the selected communication path group is provided with so-called redundancy so as to perform robust routing that enables communication even in an environment where the situation changes such that one relay device 3 becomes unusable.

Next, the communication route network optimizing means 21 prioritizes the selected communication routes (step S30 in FIG. 4). The priority is firstly assigned in descending order of the communication reliability evaluation value of each communication path, and in the case of the same communication reliability evaluation value, in descending order of the survivability evaluation value. , It is performed in the ascending order of the number of relays.
Note that the above ranking method is an example, and steps S29 and S30 of FIG. 4 are integrated, the reliability evaluation value, the survivability evaluation value, and the number of relays are weighted, and the priority order is determined by the combination optimization process. It may be attached or changed as necessary.

When the selected communication paths are prioritized, the communication path network optimizing means 21 creates a routing table for each information receiving apparatus 4 for each relay apparatus 3 based on the information. (Step S31 in FIG. 4). Specifically, a table as shown in FIG. 9B described later is created. In the routing table, the information of the communication route passing through the relay device 3 is shown with a priority order, and the information of each communication route shows the next relay partner.

As described above, when the creation of the routing table in the communication path network optimizing means 21 is completed, returning to FIG. 3, the relay devices 3 and the like actually perform according to the determined optimum placement of the relay devices 3. They are arranged (step S5 in FIG. 3). When the relay device 3 is arranged, the information transmitting device 2 issues a communication reliability confirmation request to each relay device 3 to confirm the communication reliability with the peripheral device designated in advance by the information transmitting device 2. , Via the communication means 24 (FIG. 3
Step S6).

Upon receiving the request, each relay device 3 communicates with the designated peripheral device and confirms the communication state such as the bit error rate (step S7 in FIG. 3). And
The confirmed communication state is returned to the information transmitting device 2 (step S8 in FIG. 3). The information transmitting device 2 collects the information of the communication status returned from all the relay devices 3 that were able to communicate (step S9 in FIG. 3), and analyzes the contents in the communication path network optimizing means 21 ( Step S1 in FIG.
0). As a result of the analysis, if the evaluation value of the communication reliability or the survivability of each communication route according to the current communication situation is different from the evaluation value used at the time of creating the routing table (step S4), the latest evaluation value is set. The routing table is updated by using this (step S11 in FIG. 3). Update is
The procedure is based on the procedure for creating the routing table shown in FIG.

The updated routing table is transmitted from the information transmitting device 2 to each relay device 3 (step S12 in FIG. 3), and each relay device 3 stores its own routing table in the storage means 31 ( Step S13 of FIG. 3).

As described above, the preparation for transmitting the information to the information receiving device 4 is completed, so that the information transmitting device 2 transmits the information to the information receiving device 4 (step S14 in FIG. 3). Specifically, according to the communication path having the highest priority to the information receiving device 4 which is going to transmit the information, the information transmitting device 2
The information is transmitted to the next relay device 3.

Each relay device 3 for relaying information transmits information to the next device according to the priority order based on the stored routing table and relays the information (step S15 in FIG. 3). FIG. 7 is a flowchart showing a specific procedure example of the relay process of information performed by each relay device 3. When the relay device 3 receives the information to be transmitted from the previous device, the communication control unit 32 identifies which information receiving device 4 the information is to be transmitted to (step S41 in FIG. 7).

Next, the communication control means 32 retrieves the routing table for the information receiving device 4 from the storage means 31, selects the route with the highest priority from the communication routes shown therein, An instruction to radiate a radio wave is issued to the next relay device 3 on the route (step S4 in FIG. 7).
2). The next relay device 3 may be the information receiving device 4 that is the information transmission destination.

After the radio wave is emitted, the timer set to a predetermined time is activated (step S43 in FIG. 7), and if there is a reply from the relay device 3 which emits the radio wave within the timer time (step S44 in FIG. 7). Yes), it is determined that the information has been normally transmitted, and the relay in the relay device 3 ends (step S45 in FIG. 7).

On the other hand, if there is no reply within the timer time (no step S44 in FIG. 7), it is judged that the communication route cannot be used, and whether or not there is a communication route of the next priority in the routing table. I will check. If there is no next priority communication path (step S46 in FIG. 7).
No)), the fact that communication is not possible is returned to the device in front of the communication path, and the relay of information is completed (step S in FIG. 7).
48).

If there is a communication path with the next priority (there is step S46 in FIG. 7), that communication path is selected and a radio wave is radiated to the next relay device 3 on that path (see FIG. 7). Step S47). After the radio wave emission, as shown in FIG. 7, is there a reply from the radio wave emission destination within the timer time in the procedure from step S43 described above (step S4 of FIG. 7)?
4), or there is no communication path whose priority is set in the routing table (step S46 in FIG. 7).
Repeatedly until (No), the relay process in the relay device 3 is completed.

The relay processing is performed in each relay device 3 as described above, and the information finally transmitted from the information transmitting device 2 is transmitted to the information receiving device 4 of the transmission destination. After the information is transmitted, the processing from step S6 of FIG. 3 is repeated as necessary or at predetermined time intervals, that is, the confirmation of the communication state and the updating of the routing table based on the confirmation are repeated, and the information receiving device 4 is notified. When transmitting the information, the information is transmitted through the communication route based on the latest routing table in which the information regarding the new communication state is reflected. Regarding the updated routing table, only the updated part may be sent to the relay device 3. When updating the routing table, the routing table may be manually rewritten.

Further, when it is confirmed that the relay device 3 becomes unusable due to a failure or the like during the confirmation of the communication state (step S16 in FIG. 3), the relay device may be relayed as necessary. Optimal placement processing of the device 3 (step S in FIG. 3)
You may try again from 2).

FIG. 8 is a diagram showing one embodiment using the communication system 1. In the embodiment shown in the drawing, it is assumed that information is transmitted from one information transmitting device C to three information receiving devices S1 to S3 by using nine relay devices R1 to R9. The survivability evaluation value in the relay device and the bit error rate between each two devices are shown. Figure 9
(A) shows the survivability evaluation value of each relay device in this embodiment, and (b) shows the routing table of the relay device R2 in this embodiment.

In FIG. 6A, each survivability evaluation value is calculated based on the above-mentioned expression (3) and the evaluation value calculation method illustrated in FIG. Further, FIG. 3B shows a routing table in the case where the information transmission destination is the information receiving device S1, and the priority order, the next relay device, the number of relays, and the communication reliability for each existing communication path. Information such as the evaluation value and the survival evaluation value is included. In the example shown here, the method by step S30 of FIG. 4 described above is used for ranking the communication paths. Therefore, the communication paths of No. 1 and No. 7 in the figure are first prioritized by the communication reliability evaluation value (1), and by the survivability evaluation value, No. 7 is given priority 1, No. 1 is given priority 2, and No. 2 and No. 8 are given. For the communication path,
Both have the same communication reliability evaluation value (0.5) and survivability evaluation value (0.5), but the route of No. 8 is set to priority 3 according to the number of relays.

In the routing table of the relay device R2, the reliability evaluation value and the like can be automatically changed based on the communication state by setting when communicating with the surrounding relay devices. It is also possible to automatically change the priority order based on the changed evaluation value. In this way, the relay device 3 may update the routing table by itself based on the obtained information on the communication state.

Further, when returning information from the receiving device which has received the information, the information may be returned by the same routing method, or the communication path used at the time of transmitting the information is preferentially selected and returned. You may do it.

As described above, in the communication system 1 according to the present embodiment, only communication for confirming the communication state based on the designation of the information transmitting device 2 is performed as necessary, and the conventional method is used. Since each device does not repeatedly communicate with other devices as described above, the number of communications can be suppressed, and it is effective when discoverability such as wireless communication in a battlefield is important. On the other hand, when information is transmitted based on the routing table reviewed according to the latest communication status, and the situation changes after the routing table is updated, the priority order is selected from the multiple communication routes in each relay device. Since the route is selected in accordance with the above, it is possible to select a proper route even in an environment where the communication status changes. In the case of the present embodiment, communication with high reliability and survivability is performed. it can.

In this embodiment, a wireless communication means is assumed, but the contents of the present invention can be applied to a wired communication system or a wireless and wired communication system.

The protection scope of the present invention is not limited to the above-mentioned embodiments, but extends to the inventions described in the claims and their equivalents.

[0062]

As described above, according to the present invention, the number of communications can be suppressed as compared with the conventional system in which each device repeats communications with other devices at any time, while the routing table is created with the latest information. Moreover, since a plurality of routes with priorities are secured, it is possible to transmit information through an appropriate communication route even in an environment where the communication status changes.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a device configuration diagram according to an embodiment of a communication system to which the present invention has been applied.

FIG. 2 is a diagram showing an internal configuration of each device constituting the communication system 1 according to the present embodiment.

FIG. 3 is a flowchart exemplifying a procedure of routing and information transmission based on the routing performed in the communication system 1 according to the present embodiment.

FIG. 4 is a diagram showing an example of a procedure for creating a routing table performed by the information transmitting device 2.

FIG. 5 is a diagram illustrating each item for calculating a communication reliability evaluation value and a method of calculating the evaluation value.

FIG. 6 is a diagram exemplifying each item for calculating a survivability evaluation value and a method of calculating the evaluation value.

FIG. 7 is a flowchart showing a specific procedure example of a relay process of information performed by each relay device 3.

FIG. 8 is a diagram showing one embodiment using the communication system 1.

9 is a diagram showing an example of a survivability evaluation value and a routing table in the case of the embodiment shown in FIG.

FIG. 10 is a diagram showing an example of a configuration of a conventional communication system.

[Explanation of symbols]

1 communication system 2 Information transmitter 3 relay devices 4 Information receiver 5 Information transmitter 6 Repeater 7 Information receiver 21 Communication path network optimization means 22, 31, 41 storage means 23, 32, 42 Communication control means 24, 33, 43 Communication means 25, 34, 44 Display / input / output means 51, 61, 71 communication control means 52, 62, 72 storage means 53, 63, 73 Communication means 54, 64, 74 Display / input / output means

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Claims (12)

[Claims] 1. A routing method in a communication network composed of an information transmitting device, a plurality of relay devices, and an information receiving device, wherein the information transmission is performed before information is transmitted from the information transmitting device to the information receiving device. The device selects a plurality of communication routes from among the communication routes existing in the communication network based on a predetermined evaluation index, determines the priority of the selected communication routes, and selects the selected communication including the priority. A first step of transmitting information about a route to each of the relay devices as a routing table, and, when transmitting information from the information transmitting device to the information receiving device, each of the relay devices receiving the transmission information to be transmitted is , Determining a communication route based on the transmitted routing table, and then relaying the next communication route on the determined communication route. Routing method characterized in that it comprises a second step of transmitting the location or sending information to the received in the information receiving apparatus. 2. The information transmission device according to claim 1, wherein the routing table transmitted by the information transmission device to each of the relay devices is based on information about a communication state acquired by each of the relay devices as appropriate. A routing method characterized by being updated in a relay device. 3. The communication path according to claim 1 or 2, wherein the communication path is determined by the relay device based on the priority, and the communication path having the highest priority among the communication paths available at the time of the determination. A routing method characterized by being performed by selecting. 4. The routing method according to claim 1, wherein the predetermined evaluation index includes communication reliability and / or survivability of each communication path. 5. The routing method according to claim 4, wherein the communication reliability of each of the communication paths is obtained based on the communication reliability of each of the paths between the two devices forming the communication path. 6. The routing method according to claim 4, wherein the survivability of each of the communication routes is obtained based on the survivability of each of the relay devices on the communication route. 7. The method according to any one of claims 1 to 6, further comprising: when the receiving device receiving the transmission information returns the information to the transmitting device, the receiving device includes the first and second receiving devices. The transmitting device in step 1 and the transmitting device as the receiving device in the first and second steps, and execute the first and second steps, or by the communication path through which the transmission information is transmitted. ,
A routing method comprising a step of executing a reply of the information. 8. A communication system for constructing a communication network, comprising an information transmitting device as a source of information, a plurality of relay devices for relaying the information, and an information receiving device as a destination of the information. That is, before transmitting information from the information transmitting device to the information receiving device, the information transmitting device selects a plurality of communication routes from among the communication routes existing in the communication network based on a predetermined evaluation index. Select and determine the priority order of the selected communication path, and transmit the information about the selected communication path including the priority order to each of the relay devices as a routing table, and the information transmission device to the information reception device. When transmitting, each of the relay devices that received the transmission information to be transmitted determines a communication route based on the transmitted routing table, By transmitting the transmission information thus received to the next of the relay apparatus or the information receiving apparatus on the communication path the determined communication system, characterized by carrying out the relay of the information. 9. The information transmission device according to claim 8, wherein the routing table transmitted by the information transmission device to each of the relay devices is based on information about a communication state acquired by each of the relay devices as appropriate. A communication system characterized by being updated in a relay device. 10. The communication path according to claim 8 or 9, wherein the communication path is determined by the relay device based on the priority, and the communication path having the highest priority among communication paths available at the time of the determination. A communication system characterized by being selected. 11. An information transmitting apparatus for transmitting information to an information receiving apparatus using a plurality of relay apparatuses, wherein the information is transmitted based on a predetermined evaluation index before transmitting the information to the information receiving apparatus. Selecting a plurality of communication routes as candidates for the communication route to be used at the time of transmission, determining the priority when using the selected communication route, and using the information about the selected communication route including the priority as a routing table. An information transmitting device, which transmits to each relay device. 12. The information transmission device according to claim 11, wherein the routing table transmitted to each of the relay devices is appropriately updated based on information regarding a communication state transmitted from each of the relay devices.