EP1861953A1

EP1861953A1 - Telecommunication wide area network, remote supervision system comprising said network, gateway and routing module therefor, and method for managing the routing path

Info

Publication number: EP1861953A1
Application number: EP06726047A
Authority: EP
Inventors: Serge Slawy; Adrien Bruno
Original assignee: France Telecom SA
Current assignee: Orange SA
Priority date: 2005-03-09
Filing date: 2006-03-08
Publication date: 2007-12-05
Also published as: WO2006095091A1

Abstract

The invention relates to a telecommunication wide area network comprising a common routing module (90) which is connected to each of the nodes of a local radio network by means of at least one gateway. Said common routing module can run a routing algorithm in order to establish, in place of the local radio nodes, a new path for forwarding the messages between any one of the local radio network nodes and another node of said local radio network in the event of one of the local radio network nodes failing.

Description

HIGH DISTANCE TELECOMMUNICATION NETWORK, TELESURVEILLANCE SYSTEM INCORPORATING THIS NETWORK, GATEWAY AND ROUTING MODULE FOR THIS NETWORK, AND METHOD FOR MANAGING

ROUTING ROUTE

The present invention relates to a long distance telecommunication network, a remote monitoring system incorporating this network, a routing path management method, and a gateway and a routing module for this network.

There are telecommunication networks including:

several nodes connected to each other to form a radio local area network in which there are several possible paths for conveying a message to a node and / or coming from a node, at least one of these nodes being a gateway connecting this local area network to a wireless telephony network, and a plurality of these nodes having a memory in which at least one routing path is recorded for routing a message between this node and one of the other nodes of the local area network, and a routing algorithm allowing the node having a memory containing a routing path to automatically establish a new routing path for routing a message between that node and another node of the local network in the event of a failure of one of the nodes of the network. local network.

In existing radio local area networks, each node further comprises a routing module adapted to execute the routing algorithm, so as to automatically establish the new routing path to be used by this node. Thus, each node of the network must be able to execute a large amount of operations to determine this new routing path. This complicates the architecture of each node and also increases their energy consumption.

The invention aims to remedy this drawback by proposing a telecommunication network in which the number of operations performed by each node to establish a new routing path is reduced. The subject of the invention is therefore a telecommunication network comprising a common routing module connected to each of the nodes of the local radio network via the gateway (s), this common routing module being able to execute the routing algorithm. to establish, in place of the nodes of the radio local network, a new path for conveying messages between any one of the nodes of the radio local area network and another node of this radio local area network in case of failure of one of the nodes of the local radio network. In the above telecommunication network, the nodes no longer need to execute the routing algorithm themselves to establish the new routing path in case of failure of one of the nodes. The number of operations that each node must be able to perform is therefore reduced, which further limits the energy consumption of each node.

The embodiments of this telecommunication network may comprise one or more of the following characteristics: a fault detector connected to the nodes of the local radio network via the gateway (s), this detector being able, in place of the nodes, to automatically detect a routing path become unusable for transmitting and / or receiving a message in the radio local area network;

- The fault detector - is able to automatically trigger the establishment by the common routing module of a new routing path in case of detection of a failure;

the common routing module and / or the fault detector are connected to the or each gateway via the global spider web; the memory of the nodes of the radio local network contains only a single routing path defining the path for conveying a message from this node to the one or one of the gateways;

the common routing module is also able to record the or each new established path in the memory of the or each node concerned;

the or each gateway comprises:

. a radio modem capable of transmitting a message to the other nodes of the radio local network and / or receiving a message from the other nodes of the radio local area network, and

. a wireless telephone modem capable of transmitting the messages received by the radio modem over a wireless telephone network and / or receiving from the wireless telephone network the messages to be transmitted by the radio modem on the radio local network.

These embodiments of the telecommunication network also have the following advantages: thanks to the fault detector, the nodes no longer need to perform this task of detecting a failed node themselves, which reduces the number of operations performed by each node; the automatic triggering of the establishment of new routing paths in the event of failure of one of the nodes ensures the robustness of the local network; the use of the global spider web facilitates the accessibility of the local network from anywhere on the earth;

the use of a single routing path for each node equipped with a memory simplifies the architecture of the telecommunication network. The invention also relates to a remote monitoring system comprising:

a telecommunication network as described above;

at least one sensor capable of generating a measurement intended to be transmitted via the telecommunication network and / or at least one controllable actuator capable of receiving a command transmitted via the telecommunication network, this sensor and / or this actuator being directly connected to a node of the radio local network,

a module for processing the measurements transmitted by each sensor and / or for controlling each actuator able to transmit and / or receive messages via the telecommunications network, this processing module being connected to the local radio network by means of intermediate of the or one of the bridges.

The embodiments of this system may include the following characteristic: only the nodes of the radio local network directly connected to a sensor comprise a memory in which at least one routing path is recorded.

The invention also relates to a gateway and a routing module adapted to be implemented in the telecommunications network above. The subject of the invention is also a method of remotely managing a routing path of a node of a radio local network adapted to be implemented in the long-distance network described above, in response to the detection a faulty routing path that has become unusable between two nodes of the radio local area network. This process comprises:

a step of sending to at least one of the two nodes of a new routing path established by the common routing module,

a step of replacing in the memory of the or each node of the faulty routing path by the new routing path, followed by

a phase of use by the node of the new routing path to transmit a message.

The invention will be better understood on reading the description which will follow, given solely by way of example and with reference to the drawings, in which: FIG. 1 is a schematic illustration of the architecture of a control system. remote monitoring and telecontrol equipped with a telecommunication network; and

FIG. 2 is a flowchart of a remote monitoring method implemented in the system of FIG. 1.

FIG. 1 represents a system, designated by the general reference 2, remote monitoring and telecontrol of remote actuators equipped with:

sensors capable of generating a measurement of a physical quantity, such as, for example, a water level, a temperature or the like,

- controllable actuators able to act in response to an order, a module 4 for processing the measurements generated by the sensors and transmitting commands for the actuators, and

a telecommunication network 8 connecting the module 4 to all the sensors and actuators of the system 2.

To simplify FIG. 1, only five sensors 10 to 14 and two actuators 16 and 17 have been shown.

For example, the actuator 16 is able to trigger an alarm while the actuator 17 is able to close or open a barrier.

These sensors and actuators are here placed in hard-to-reach geographical areas and are, for example, intended to prevent flooding.

The module 4 is, for example, a geographic information module for representing on a geographical map the position of each of the sensors and actuators as well as the measurements of the sensors and the state of the actuators. The module 4 is also able to store in a memory 20 the various measurements received and the different commands transmitted to the actuators. The module

4 is conventional and will not be described here in more detail.

The network 8 is formed by the combination of three subnetworks, an AD-HOC radio local area network 30, a wide area wireless telephony network 32 and the global spider web 34, referred to herein as an Internet network.

AD-HOC networks are networks in which nodes automatically connect to each other to form a local network. Such a network therefore does not require heavy hardware infrastructure, such as base stations or access points. In these AD-HOC networks, a node can thus be easily added or removed without any manual intervention being necessary to reconfigure this network. LAN 30 uses the frequencies of 868, 915 and 2400 MHz.

For more information on AD-HOC networks, it is possible to consult the following link: http: // acts. SSTIC. org / SSTIC03 / Detection_Intrusion_reseaux _without_fil_ad_hoc / SSTIC03-article-Jouga_Percher-Dection_ Intrusions__reseaux_without_fil_ad_hoc.pdf

The network 30 is therefore formed of nodes connected to each other via wireless radio links. Here, the network 30 comprises three types of nodes: radio modules, relays and gateways.

Radio modules are connected to sensors and / or actuators by any type of media. Each radio module is equipped with a memory containing at least one routing path. The routing path of each radio module defines the path to follow to route a message sent by this radio module to one of the nodes of the network 30 forming a gateway. Here, each radio module comprises a single routing path since it is not expected that the different radio modules of the network 30 communicate with each other.

The radio modules are able to receive a new routing path and replace their current routing path with the new path received. By way of illustration, five radio modules 40 to 44 have been represented in FIG. 1 equipped with respective memories 45 containing their routing path. Here, only the radio modules are equipped with memory 45 containing a routing path, which simplifies the architecture and operation of the other types of nodes.

The sensors 10 to 14 and the actuators 16 and 17 are connected to these radio modules as follows:

the sensor 10 is directly connected to the module 40; the sensors 11 and 12 are directly connected to the module 41;

the sensor 13 is directly connected to the module 42; the sensor 14 is directly connected to the module 44;

the actuator 16 is directly connected to the module 43; and

the actuator 17 is directly connected to the module 44.

The second type of node is a gateway connecting the network 30 to the network 32 or directly to the network 34. Here, each gateway assembles the messages sent by the different radio modules of the network 30 before transmitting them without modifying them to the module 4 by the Intermediate networks 32 and / or 34. In the opposite direction, each gateway also collects messages sent by the module 4 to the radio modules before transmitting them to these radio modules. The network 30 comprises, for example, here three gateways 50 to 52 connecting the network 30 to the network 32. These gateways 50 to 52 are identical and only the gateway 50 will be described in detail.

The gateway 50 is equipped with a radio modem (modulator-demodulator) 54 and a wireless telephone modem 56. The modem 54 is able to send and receive messages from the radio terminals of the network 30.

The modem 56 is able to exchange messages with the module 4 via the network 32. Here, the gateway 50 is equipped with a single antenna 57 common to the modems 54 and 56. For this purpose, the antenna 57 is connected to the modems 54 and '56 via a diplexer 58. The modems 54 and 56 are also connected to each other via an information transmission bus 60 so as to allow the exchange of messages received or transmitted between these two modems. Typically, the gateway 50 is equipped with a battery or solar panels 62 to power its various electronic components.

The network 30 also includes a gateway 66 connecting the network 30 directly to the Internet 34 via a satellite link 68. Here, this gateway 66 is identical to the gateway 50 except that the modem 56 is replaced by a satellite modem 70 capable of establishing the satellite link 68. The other elements are identical to those of the gateway 50 and therefore bear the same reference numerals.

The third type of node is a relay or repeater used to enlarge the coverage area of the gateways 50 to 52 and 66. These relays are only able to amplify and rebroadcast the received radio messages without modifying them. has six relays arranged as follows:

a relay 74 arranged between the gateway 50 and the radio module 41, two relays 75 and 76 arranged successively between the radio module 42 and the gateway 51,

three relays 77, 78 and 79 arranged successively between the gateway 51 and the radio module 43, and

a relay 80 disposed between the gateway 52 and the radio module 44.

Each node of the network 30 corresponds to an address. In the rest of this description, the addresses of the gateways 50 to 52 and 68 are respectively denoted by P1, P2, P3 and P4. Relay addresses 74 to 80 are noted respectively R1 to R7 and the addresses of the radio modules 40 to 44 are noted respectively M1 to M5.

Using these notations, the set of possible paths for exchanging information between a gateway and a radio module of the network 30 is summarized in the following table:

In this table, each line represents a routing path for routing a message between this node and one of the gateways. Thus, each path is formed by the concatenation of the address of the gateway, the address of the radio module and, if they exist, the address of the intermediary relay (s). Here, each routing path also includes the address XXXXXX of the sensor or actuator concerned by the message.

These different paths are illustrated in Figure 1 by wavy arrows connecting the different nodes together. The wavy arrows in solid lines represent the default routing paths while the dashed arrows represent the backup routing paths. Here, the addresses P1 to P3 correspond, for example, to the telephone numbers assigned to the gateways 50 to 52 on the network 32.

The network 32 is, for example, a GSM network (Global System for Mobile Communication) or a GPRS network (General Packet Radio Service). The network 32 is connected to the Internet 34 via an M2M (machine-to-machine) interface 84 for decoupling a business part where the data is processed from a sensor part where the data are measured and acquired. . This interface 84 is associated with a memory 86 for storing messages.

Here, for example, the interface 84 comprises a detector 88 for failure of a routing path used by one of the nodes of the network 30. The operation of this detector 88 will be described in more detail with respect to the figure 2.

The network 8 also comprises a routing module 90 connected to, and able to communicate with, each of the nodes of the network 30 via the Internet 34, and the gateway 66 or via the Internet network 34, the interface 84, the network 32 and the gateways 50 to 52 and 66. This module 90 is able to execute a routing algorithm 92 stored in a memory 94. The routing algorithm automatically establishes a new routing path for each of the radio modules when one of the nodes of the network 30 is faulty. For this purpose, the algorithm uses the routing table previously described. This routing table is, for example, stored in the memory 94.

The module 90 is also able to record the or each new path established in the memory 45 of the radio module concerned. Here, by way of illustration, the modules 4 and 90 are implemented in the same management computer platform 96 located in an environment protected from external aggression and far from the network 30. The platform 96 and the module 90 n so do not have to be as robust as the radio modules.

The operation of the system will now be described with reference to the method of FIG.

During an initialization phase 100, the routing table previously described is recorded, in a step 102, in the memory 94. This table is, for example, automatically established using the network's autoconfiguration functionalities. Also during this phase 100, during a step 104, the default routing path used by each of the radio modules is stored in its memory 45.

Then, during a message transmission phase 106 the routing module 4 sends a message to one of the sensors or to one of the actuators. This message is associated with the routing path to reach the sensor or the actuator who is the recipient.

Thus, during a step 108, the module 4 sends the message via the Internet 34 to the interface 84. The interface 84 records, in a step 110, the messages thus received in its memory 86.

Then, periodically, the interface 84 reads the messages recorded in a step 112 and sends them, in a step 114, to the gateway whose address is in the routing path. For this purpose, during step 114, the interface uses the network 32 by default.

During a step 116, the destination gateway of the message transmits this message to the relay or to the radio module whose address is indicated in the routing path. If the radio module can only be reached via a relay, in a step 118, the relay whose address is in the routing path retransmits the message to either the next relay or the radio module which is the recipient. Step 118 is repeated as many times as there are relay addresses in the routing path.

Finally, during a step 120, the radio module receives the message. In response to the receipt of a message, the radio module immediately sends, during a step 122, an acknowledgment to the module 4.

In a step 124, the detector 88 verifies that the acknowledgment corresponding to the transmitted message is actually received within a predetermined period of time. If so, the method returns to step 112 to send another message stored in memory 86 and erases the correctly transmitted message.

If not, that is, if the acknowledgment is not received within the predetermined time, this means that one of the nodes on the routing path is probably failing and that path routing is unusable for transmitting a message.

For example, in the remainder of this description, it will be assumed that the destination node and the radio module 44 and that the failed node is the relay 80.

Under these conditions, during a step 128, the detector 88 automatically triggers the establishment by the module 90 of a new routing path for the radio module 44.

Therefore, the module 90 executes, during a step 130, the routing algorithm 92. More specifically, during this step 130, the module 90 selects from the routing table stored in the memory 94, during the phase 100, another routing path based on pre-established criteria among other possible routing paths. For example / pre-established selection criteria consist of choosing the shortest path or minimizing energy consumption. In the case of the radio module 44, when the default path no longer works, the new routing path established is either the one passing through the gateway 66 and the satellite link 68, or the one passing through relay 77 and gateway 51. Here, it will be assumed that the new routing path selected is the one passing through the satellite link 68.

Once the new routing path has been established, the module 90 sends a service message, during a step 132, to the module 44, using for this purpose the new routing path established, that is to say here, in via the satellite link 68. This service message contains the new routing path. In response to the receipt of this service message, the radio module 44 replaces, in a step 134, the default routing path stored in its memory 45 by the new routing path received. Therefore, any further attempt to communicate with the radio module 44 will be done via the satellite link 68 as the routing path is not reset to its default value.

Once the new routing path is stored in the memory 45 of the radio module 44, the method returns to step 112 to send the message to this radio module 44 using this time the new routing path.

During the operation of the system 2, during a phase 136 of receiving messages, one of the radio modules takes the initiative to transmit a message to the module 4. For this, the radio module associates, during a step 140, the message to the routing path stored in its memory 45. This message is then sent, in a step 142, on the network 30.

If the routing path includes the address of a relay, it receives, in a step 144, the message and checks, in a step 146, if its address corresponds to that indicated in the routing path associated with the message. If not, the relay does not retransmit this message. If so, this relay amplifies and then re-transmits the message during a step 148. Steps 146 and 148 are repeated until the gateway whose address corresponds to that indicated in the routing path is reached. When the message is received by the radio modem 54 of this gateway, it is transmitted via the bus 60 to the modem 56, if the gateway is one of the gateways 50 to 52 or the modem 70 if the gateway is the gateway 66. The modem 56 retransmits, in a step 150, the message thus received to the module 4 via the network 32, the interface 84 and the Internet 34. The modem 70, meanwhile , in step 150, re-transmits the message thus received to the module 4 via the satellite link 68 and the network 34.

When the message is received by the module 4, the latter processes its content, during a step 152.

Many other embodiments of the system 2 are possible. For example, alternatively, the relays are also able to be directly connected to sensors and / or actuators and in addition to the relay function perform the same functions as those described for the radio modules.

Here, the fault detector has been described as being implemented in the interface 84. However, as a variant, it is implemented in the same platform that the one used for the routing module 90. Conversely, the module 90 can also be implemented in the interface 84.

Here, the routing path has been described as being recorded only in the radio modules and as having the address of all the intermediate nodes to be crossed before reaching a gateway. As a variant, the routing path comprises only the address of the next node of the network to which the messages should be directed. The routing path is registered in each node of the network, including those forming relay or gateway. Thus, the messages are routed step by step to the appropriate gateway. The processing module 4 can be implemented in a computing platform having an Internet address different from that of the platform in which the module 90 is implemented. In this variant, the routing path also includes the Internet address of the platform in which is implemented the processing module so that the radio modules can send a message to this module 4.

Finally, the network 8 has been described in the particular case, where only the routing of messages between a node of the network 30 and the module 4 is managed by the module 90 outside the network 30. However, alternatively, the module 90 is also adapted to establish routing paths for routing messages from any node of the network 30 to any other node of the network 30.

Claims

1. A long distance telecommunication network comprising: - several nodes (40 to 44, 74 to 78, 50 to 52, 66) connected to each other to form a radio local area network in which there are several possible paths for conveying a message to a node and / or from a node, at least one of these nodes being a gateway (50 to 52) connecting this local area network to a wireless telephony network (32), and several of these nodes (40). at 44) having a memory (45) in which is stored at least one routing path for conveying a message between that node and one of the other nodes of the local network, and

a routing algorithm enabling the node comprising a memory containing a routing path, to automatically set up a new routing path for conveying a message between this node and another node of the local network in the event of a failure of one of the nodes of the local network, characterized in that the telecommunication network comprises a common routing module (90) connected to each of the nodes of the local radio network via the gateway or gateways, this common routing module being able to execute the routing algorithm for establishing, in place of the nodes of the radio local area network, a new path for routing messages between any one of the nodes of the radio local area network and another node of this radio local area network in the event of a failure of the one of the nodes of the radio local network.

2. Network according to claim 1, characterized in that the network comprises a detector (88) of failure connected to the nodes of the local radio network by via the gateway or gateways (50 to 52, 66), this detector being able, in place of the nodes, to automatically detect a routing path that can no longer be used to transmit and / or receive a message in the local network radio.

3. The network of claim 2, characterized in that the fault detector (88) is adapted to automatically trigger establishment by the common routing module of a new routing path in case of detection of a failure.

4. A network according to any one of the preceding claims, characterized in that the common routing module (90) and / or the fault detector (88) are connected to the or each gateway via the fabric of spider (34).

A network according to any one of the preceding claims, characterized in that the memory (45) of the nodes of the wireless LAN contains only a single routing path defining the path for conveying a message from that node to the one or the other bridges.

6. Network according to any one of the preceding claims, characterized in that the common routing module (90) is also adapted to record the or each new path established in the memory of the or each node concerned.

7. Network according to any one of the preceding claims, characterized in that the or each gateway comprises:

a radio modem (54) capable of transmitting a message to the other nodes of the radio local area network and / or receiving a message from the other nodes of the radio local area network, and a wireless telephone modem (56) capable of transmitting messages received by the radio modem over a network wireless telephony and / or receive from the wireless telephone network the messages to be transmitted by the radio modem on the local radio network.

8. Remote monitoring system, characterized in that this system comprises: a telecommunication network (8) according to any one of the preceding claims,

at least one sensor (10 to 14) capable of generating a measurement intended to be transmitted via the telecommunication network and / or at least one actuator

(16, 17) capable of receiving a command transmitted via the telecommunications network, the sensor and / or actuator being directly connected to a node of the radio local network, - a module (4) for processing the transmitted measurements by each sensor and / or control of each actuator able to transmit and / or receive messages via the telecommunication network, this processing module being connected to the radio local network via the or a bridges (50 to 52, 66).

9. System according to claim 8, characterized in that only the nodes of the radio local network directly connected to a sensor comprise a memory in which is recorded at least one routing path.

10. Gateway capable of being implemented in a long distance telecommunication network according to claim 7, characterized in that the gateway comprises: a radio modem (54) capable of transmitting a message to the other nodes of the local radio network and / or receive a message from the other nodes of the radio local area network, and a wireless telephone modem (56) capable of transmitting the messages received by the radio modem over a wireless telephone network and / or receiving data from. wireless telephone network the messages to be transmitted by the radio modem on the local radio network.

11. Routing module adapted to be implemented in a long distance telecommunication network according to any one of claims 1 to 7, characterized in that this routing module is adapted to be connected to each of the nodes of the local network. via the gateway or gateways (50 to 52, 66), this routing module being able to execute the routing algorithm to establish, in place of the nodes, a new path for routing the messages between the any of the nodes of the radio local area network and another node of this radio local area network in case of failure of one of the nodes of the radio local area network.

12. A method for remote management of a routing path of a node of a radio local network adapted to be implemented in a long distance network according to any one of claims 1 to 7, characterized in that , in response to the detection of a faulty routing path that has become unusable between two nodes of the radio local area network, the method comprises: a step (132) of sending to at least one of the two nodes of a new path routing established by the common routing module,

a step (134) of replacing in the memory of the or each node of the faulty routing path by the new routing path, followed by

- a phase (136) of use by the node of the new routing path to transmit a message.