FR3087610A1 - EXCHANGE OF DATA IN AN INFRASTRUCTURE OF CONNECTED OBJECTS - Google Patents

Abstract

The invention relates to a method for managing a data transport subnetwork (11) which comprises connected objects (loT 1) and connection gateways (GW1, GW2) for the communication of said connected objects with other connected objects (loT2) belonging to other subnets (12). The method comprises a procedure (21) for assigning priority levels (P1, P2) respectively to gateways (GW1, GW2) of the subnetwork, as well as a procedure (22) for discovering the gateways of the subnet network, by at least one connected object (loT 1) of the subnet, said discovery procedure comprising the broadcasting (220) by the connected object (loT 1) of a query message (BCM) in the sub- network (11), the reception (221,222) by the connected object of a response message sent by each of the gateways of the subnet, which contains an identifier and the priority level of said gateway, and a classification (223) by the connected object of the subnetwork gateways in order of their respective priority levels.

Description

EXCHANGE OF DATA IN AN INFRASTRUCTURE OF CONNECTED OBJECTS The present invention relates to the field of connected objects and, in particular, the exchange of data in a network infrastructure comprising connected objects. The invention relates in particular to a method for managing a data transport subnetwork which comprises connected objects and connection gateways for the communication of said connected objects with other connected objects belonging to other subnets. , as well as a communication system capable of implementing the method, a computer program having instructions for implementing the method, and a recording medium for said computer program.

[Prior art] Historically, the addressable entities on the Internet were only digital information elements, namely HTML pages or other files accessible online, and identifiable by website URLs, by example. Considered the third Internet revolution, the Internet of Things (IoT) (Internet of Things, or loT) can be viewed as the extension of the Internet to physical elements.

The Internet of Things refers to all objects connected to the Internet and corresponds to the field of Information and Communication Technologies (or ICT) which is booming. The electronic devices involved in these applications are called connected objects, in the sense that they interact through local subnets that can be connected to a central high-speed network like the Internet.

Thus, a definition of the Internet of Objects is proposed in the work entitled THE INTERNET OF OBJECTS, by Pierre-Jean Benghozi, Sylvain Bureau, and Françoise MassitFolléa published by Éditions de la Maison des sciences de l'homme , Chapter 1, pp. 15-23, as being "a network of networks which allows, via standardized and unified electronic identification systems, and wireless mobile devices, to directly and unambiguously identify digital entities and physical objects and thus power retrieve, store, transfer and process, without discontinuity between the physical and virtual worlds, the related data. The uses of connected objects are very varied and can range from the field of health to that of home automation via mobile phones, the concept of intelligent environment and in particular of smart city (or "Smart City"). , in English), surveillance (in English: "monitoring") of industrial installations, transport and logistics, autonomous cars, agriculture, etc. Connected objects increasingly invade our daily lives. There were 4.9 billion objects in 2015. We are talking about 25 to 150 billion connected objects in 2025. In addition to this exponential growth, there is a very wide variety of application areas: health, transport, commerce, Automation...

The number and diversity constitute a real technical challenge for the transport of data for all of these objects. In particular, the Internet connectivity of these connected objects can be variable over time. In some cases, the connectivity may not be permanent, and may evolve following, for example, a hardware or software problem affecting a gateway. In other cases, it can be multiple, that is to say it can be performed simultaneously by more than one Internet connection gateway, in particular with the implementation of the concept of aggregation of links.

It has been proposed methods of communication of connected objects in which a connection gateway was configured to determine a first communication path and first communication resources between the source terminal and the destination terminal (CN 102685839). A method has also been proposed for assigning a gateway according to the characteristics of the connected object concerned (US2016 / 018043).

However, to date, no solution makes it possible to dynamically manage the scalability of the connectivity of subnets which may include several gateways, more or less available, managing the communication of connected objects to the outside of the subnet (eg via the Internet).

Thus, there is a need for new methods or systems for the exchange of data in an infrastructure of connected objects.

[Technical problem [0010] The invention aims to remedy the drawbacks of the prior art. In particular, the invention aims to propose a method for managing a data transport subnetwork which allows self-adaptation to fluctuations in connectivity of the subnets by taking into account the multiplicity of gateways to the Internet and the scalability over time of their connectivity. The invention further aims to provide gateways, connected objects and a data communication system capable of implementing self-adaptation to fluctuations in connectivity of subnets.

[Brief description of the invention] To this end, a first aspect of the invention proposes a method for managing a data transport subnetwork which comprises connected objects and gateways, for example gateways of connection to a main network, for the communication of said connected objects with other connected objects belonging to other subnets, for example also connected to said main network, said management method comprising:

a procedure for assigning priority levels respectively to gateways of the subnetwork, said procedure for assigning priority levels comprising:

o the selection, on the basis of exchanges of protocol messages between the gateways of the subnet, of a common prioritization function to be used to calculate the priority level of each of the gateways of the subnet; and, o the use by each gateway of the prioritization function thus selected, to calculate its own priority level on the basis of characteristics specific to the gateway; as well as :

a discovery procedure of the subnetwork gateways, by at least one connected object of the subnetwork, said discovery procedure comprising:

o the broadcast by the connected object of a query message in the subnet o the reception by the connected object of a response message sent by each of the gateways of the subnet in response to the query message , which contains an identifier of said gateway and the priority level of said gateway; and, a classification by the connected object of the gateways of the subnetwork in order of their respective priority levels, with a view to choosing one of said gateways for the transmission of data messages intended for other connected objects belonging to another or to other subnets, for example connected to the main network.

The method according to the invention allows to dynamically manage the evolution of connectivity of subnets, for example following a hardware or software problem. Thus, thanks to the invention, it is possible to carry out an auto-adaptive routing, an optimization of the transport costs of the messages and a management of the period of validity of the transmitted messages. In addition, the method according to the invention makes it possible to take advantage of the multiplicity of gateways to the Internet and the evolution over time of their connectivity. The inventors therefore propose a solution which makes it possible to meet the challenges of connectivity by proposing a process which can adapt to the diversity of connected objects but also which can cover all of the connected objects deployed, whether or not they are directly accessible by a system. centralized.

According to other optional characteristics of the process:

it further comprises, when a connected object of the subnet transmits a data message to another connected object which belongs to another subnet, preferably connected to the main network, the transmission of the data message by the transmitting connected object to the subnetwork gateway which has the maximum priority level;

it further comprises an automatic updating of the priority level of at least some of the gateways of the subnetwork, and the broadcasting or transmission by the gateways of their updated priority level, to the connected objects of the subnetwork. Thus, the method allows a connected object to quickly identify the most efficient gateway at a given time;

the automatic updating of the priority level of the gateways of the subnetwork is carried out periodically, at a frequency which is programmable at the level of each gateway. Thus, if the gateways can quickly send their priority level during a query by a connected object;

the selection of the common priority function to be used to calculate the priority level of each of the gateways of the subnetwork, includes the choice by each gateway of the most recent priority function from a set of available priority functions, on the basis of a time stamp or versioning of prioritization functions in the subnetwork;

the selected prioritization function is memorized by each gateway of the subnetwork for use by said gateway for the calculation of its own priority level on the basis of characteristics specific to said gateway;

the characteristics specific to each gateway which are taken into account by each gateway of the network, for the calculation of its own priority level, include a type of connectivity, a cost of transporting data per unit of data, a quality index of connectivity, latency, and / or transmission rate associated with the network gateway; and / or the gateways (GW1, GW2) make it possible to connect the sub-network (11) to a main network (10) to which the other sub-networks (12) are connected. Indeed, the communication of said connected objects with other connected objects belonging to other sub-networks can be carried out between sub-networks directly connected to each other or between sub-networks linked to each other via a main network. such as the internet. The possibility of managing subnetworks connected directly to each other advantageously makes it possible to be able to implement the process in a “closed cup” in an environment made up of a multitude of local area networks interconnected by one or more gateways such as for example safeties arranged in batches.

In another aspect, the invention relates to a connection gateway, preferably to a main network, for the communication of a connected object from a first subnet with other connected objects belonging to other subnets, preferably also connected to the main network, said connection gateway of the first subnetwork being characterized in that it comprises:

- A prioritization module configured to calculate a priority level of the gateway, and comprising:

o means of selection, on the basis of exchanges of protocol messages with other gateways of the first subnetwork, of a common prioritization function to be used to calculate the priority level; and, o means for calculating its own priority level on the basis of characteristics specific to it, using the selected prioritization function;

- A communication module configured to send a response message following the reception of an interrogation message broadcast by a connected object of the first subnet as part of a subnet discovery procedure, said message response comprising an identifier of said gateway and the priority level of said gateway.

According to another aspect, the invention relates to a connected object, adapted to be connected to a first subnetwork comprising several gateways, the connected object being adapted, moreover, to implement a procedure for discovering the first subnetwork and comprising for this purpose a priority access management module comprising:

- means of broadcasting a query message in the first subnet;

- Means for receiving a response message sent by each of the gateways of the subnetwork in response to the interrogation message, which contains an identifier of said gateway and a priority level of said gateway; and,

means for classifying the gateways of the subnetwork in order of their respective priority levels, with a view to choosing one of said gateways for sending data messages to other connected objects belonging to a other or other subnets According to another aspect, the invention relates to a data communication system comprising a subnetwork with connected objects and gateways, preferably for connection to a main network, for the communication of said connected objects with other connected objects belonging to other subnets, preferably also connected to the main network, in which:

the subnetwork gateways are configured to carry out a procedure for assigning priority levels respectively to each of the network gateways, and each include for this purpose:

• means of selection, on the basis of exchanges of protocol messages between the gateways of the subnetwork, of a common prioritization function to be used to calculate the priority level of each of the gateways of the subnet; and, • means for calculating its own priority level on the basis of characteristics specific to each gateway, using the selected prioritization function; and in which:

the connected objects of the network are configured to implement a procedure for discovering the gateways of the subnetwork, and each include for this purpose:

• means of broadcasting a query message in the subnetwork;

• means for receiving a response message sent by each of the gateways of the subnet in response to the query message, which contains an identifier of said gateway and the priority level of said gateway; and, • means for classifying the gateways of the subnetwork in order of their respective priority levels, with a view to choosing a gateway for sending data messages to other connected objects belonging to a other or other subnets, preferably connected to the main network.

According to another aspect, the invention relates to a connected object, belonging to a first subnetwork comprising several gateways, suitable for implementing a procedure for discovering and prioritizing the gateways of the first subnetwork and comprising for this purpose a priority access module comprising:

- means of broadcasting a query message in the first subnet;

- means for receiving a response message sent by each of the gateways of the subnetwork, which contains an identifier and the priority level of said gateway; and,

means for classifying the gateways of the subnetwork in order of their respective priority levels, with a view to choosing a gateway for sending data messages to other connected objects belonging to another or to other subnets.

Other advantages and characteristics of the invention will appear on reading the following description given by way of illustrative and nonlimiting example, with reference to the appended figures which represent:

• Figure 1, a diagram showing an architecture of local networks comprising connected objects, operating as subnets of the Internet network;

• Figure 2, a functional diagram illustrating the exchanges between gateways and two connected objects of the architecture of Figure 1, in embodiments of the method according to the invention; and, • Figure 3, a diagram showing the architecture of a gateway and a connected object according to an embodiment of the invention.

[Description of the invention] In the following description, a "connected object" is an electronic object connected wirelessly to a network and which can share information with a server, a computer, a tablet, a smartphone or any other electronic device.

The expression “sub-network” or “local network” within the meaning of the invention corresponds for example to local networks each served by at least one Internet connection gateway and to which connected objects are connected [0021] The expression “main network” within the meaning of the invention is a wide area network, at high speed, using a reliable transport protocol in connected mode, such as for example the TCP / IP protocol (TCP or “Transmission Control Protocol” being a OSI model layer 4 protocol, over IP which is an OSI model layer 3 protocol). The TCP / IP protocol is documented in IETF RFC 7931. It can be, for example, an Internet network.

The term “gateway” or “connection gateways” within the meaning of the invention means equipment ensuring the connection between equipment belonging to different networks, for example ensuring the connection of the equipment of a local network (IP addresses local) and internet services (public IP addresses). Therefore, it has both types of IP addresses. Its public IP address, assigned by the ISP, allows it to exchange data with the Internet. Its local IP address allows it to exchange data with equipment on the local network. It is generally specific and assigned by default by the ISP.

The term “priority levels” or “priority level” is understood to mean an increasing scheduling (P) according to characteristics of the type of connectivity, cost of transport, index of quality of the connectivity, etc. to calculate a value of priority which corresponds to the priority level of each gateway. In other words, if P2> P1 then the gateway having a priority level P2 will have priority over the gateway having a priority level P1.

The expression “prioritization function” within the meaning of the invention may correspond to a protocol or to a series of instructions making it possible to calculate a priority level from a given priority value and according to a predetermined function or formula .

Within the meaning of the invention "protocol message" corresponds to a message between two gateways comprising the protocol used by each of them to calculate its priority level taking into account the common prioritization function.

Within the meaning of the invention "interrogation message" corresponds to a BCM type message ("Broadcast Message" in English terminology) broadcast by an object connected to gateways and / or other objects connected to the local network .

Within the meaning of the invention "response message" corresponds to a message sent by one or more gateways in response to a query message and which includes an identifier and a priority level of the gateway in the sense of the invention.

Within the meaning of the invention "data message" corresponds to a message sent between two objects connected through at least one gateway and comprising data from a connected object.

The term "process", "calculate", "determine", "display", "extract" "compare" or more broadly "executable operation", within the meaning of the invention, an action performed by a device or a processor unless the context indicates otherwise. In this regard, operations relate to actions and / or processes of a data processing system, for example a computer system or an electronic computing device, which manipulates and transforms the data represented as physical quantities (electronic ) in the memories of the computer system or other devices for storing, transmitting or displaying information. These operations can be based on applications or software.

The terms or expressions "application", "software", "program code", and "executable code" mean any expression, code or notation, of a set of instructions intended to cause data processing to perform a particular function directly or indirectly (eg after a conversion operation to another code). Examples of program code may include, but are not limited to, a subroutine, function, executable application, source code, object code, library, and / or any other sequence of instructions designed for execution on a computer system.

By "processor" is meant, within the meaning of the invention, at least one hardware circuit configured to execute operations according to instructions contained in a code. The hardware circuit can be an integrated circuit. Examples of a processor include, but are not limited to, a central processing unit, a graphics processor, an application specific integrated circuit (ASIC) and a programmable logic circuit. A single processor or more than one other unit can be used to implement the invention.

By "coupled", in the sense of the invention, connected, directly or indirectly with one or more intermediate elements. Two elements can be coupled mechanically, electrically or linked by a communication channel.

In the claims, the term understand or include does not exclude other elements or other steps.

In the following description, the same references are used to designate the same elements. The reference signs should not be understood as limiting the scope of the invention. In addition, the various features presented and / or claimed can be advantageously combined. Their presence in the description or in different dependent claims does not exclude this possibility.

There is no solution for managing, dynamically, the scalability of the connectivity of several gateways of the same subnet so as to allow improved connectivity of the connected objects from the subnet to the objects connected to other subnets (eg via the Internet) through said gateways. Thus, the inventors have developed a new method for managing a data transport subnetwork which comprises connected objects and several connection gateways, preferably to a main network, for the communication of said connected objects with other objects. connected belonging to other subnets, preferably also connected to said main network.

The invention will be described in the context of a main network, and subnets. The invention is not limited, however, to this example, and can find applications in any configuration in which there are multiple connected subnets.

Referring to the diagram of Figure 1, a local area network architecture to which the method of the invention can advantageously be applied comprises a main network 10, on the one hand, and at least two subnets, a first sub-network 11 and a second separate sub-network 12, each connected to the main network 10. The main network 10 in the example shown, is the Internet network.

The subnet 11 includes several Internet connection gateways, such as the two gateways, a first gateway GW1 and a second gateway GW2 of the example shown. The subnetwork 12 comprises at least a third Internet connection gateway like the GW3 gateway of the example shown. In other words, the subnets 11 and 12 are local networks, a first subnetwork of which is served by at least two connection gateways.

Each of the local networks 11 and 12 includes one or more connected objects, such as the loT1 connected object of the local network 11 shown, and the loT2 connected object of the local network 12 shown, respectively. These connected objects can be, without limitation: a connected mobile phone, a connected tablet, a connected laptop, connected speakers, a connected headset, a connected webcam, etc. The invention does not intend to be limited either by the number or by the nature of the objects thus connected to the subnets 11 and 12. It can be any physical object, place or person identified by RFID chips, by example, or a barcode, an EAN code ("European Article Numbering"), an EPC code ("Electronic Product Code"), etc. Each object is identified by a unique individual code which distinguishes it from all the others within the local network concerned.

It will be noted that the identification of objects follows a heavy trend in the context of the emergence of the IoT, towards the allocation of a unique IP address specific to each connected object. This is why, in what follows, it will be considered as necessary that the unique identifier of each connected object of each subnet is an IP address. This is not, however, a prerequisite for the modes of implementing the invention. Indeed, the interface between the connected objects of the local networks and the Internet network, the connections of which are IP connections, is provided by the gateways GW1, GW2 and GW3 shown in FIG. 1, which can manage a conversion or correspondence d addresses between any address space on a subnet on the one hand, and the IP address space on the Internet on the other.

The subnets 11 and 12 can be networks specifically dedicated to connected objects such as for example:

- a Sigfox network;

- a LoRa network using the LoRaWAN protocol (acronym for "Long Range Wide-area Network") which, as its name suggests, is a long range wide area network;

- or networks based on another wireless protocol by radio waves such as for example:

a personal dimension network (or WPAN, from the English “Wireless Personal Area Networks”) such as a ZigBee network based on the IEEE 802.15.4 standard;

a Wi-Fi network; or a Bluetooth network (IEEE 802.15.1 standard); etc.

The present invention is presented as a mechanism for transporting data from loTs located in a first subnet comprising at least two gateways to other loTs located in one or more different subnets. In data communications networks, the transport layer protocols are thus intended to transport data from one application to another (we also speak of application programs), which run on respective host machines and potentially in respective local networks distant from each other, and connected together via a wide area network such as the Internet.

Modes of implementing the method according to the invention will now be described with reference to the functional diagram of Figure 2. To this end we will consider a use case in which the connected object loT1 of the local network 11 of FIG. 1 must send data to the connected object loT2 of the local network 12. For this purpose, the method makes it possible to permanently use the gateway for connection to the Internet available which offers the best connection performance.

To obtain this result, the method firstly comprises a procedure 21 for assigning priority levels, respectively to gateways of the or each subnetwork considered, namely the local network 11 in the example shown in the Figure 2. It further comprises a procedure 22 for discovering the gateways of the subnetwork, by the connected objects of the subnetwork 11, which is implemented at least by the connected object ΙοΤ1. Finally, it includes an exchange 23 of data messages and corresponding acknowledgment messages, for sending the data from the object loT1 to the object loT2, through one of the gateways GW1 and GW2 of the local network 11 , the main network 10, and the local network gateway 12.

In embodiments, procedure 21 and / or procedure 22 are initiated each time a new gateway connects to the local network 11, while being launched by said gateway. Likewise, these procedures 21 and / or 22 can be triggered in response to the detection of the disconnection of a gateway which was connected to the local network 11, due to a hardware failure for example, or even to an software day. This makes it possible to adapt the priority levels respectively associated with the gateways of the local network 11, and which are used by the connected objects of the network as will be explained below, to the evolution of the connectivity of the gateways. In addition, the procedure 22 for discovering the gateways of the subnetwork by the objects connected to the local network 11 can be launched specifically by any new object which is connected to the local network 11.

Let’s start by explaining the procedure 21 for assigning priority levels, as applied in accordance with the example shown at the gateways GW1 and GW2 of the local network 11.

This procedure 21 includes an exchange of protocol messages 210 between the gateways GW1 and GW2, which makes it possible to select a prioritization function common to the two gateways, to be used by each of them to calculate its priority level. In an exemplary implementation, the exchange comprises the sending by the gateway GW1 to the gateway GW2 of the last prioritization function F1 which it used to calculate its priority level. Conversely, the gateway GW2 sends the gateway GW1 the last prioritization function F2 that it used to calculate its priority level. These F1 and F2 functions are time-stamped and / or are labeled with a version number which indicates which is the most recent. Thus, each of the gateways is able to determine the function F to be used, as being that of the functions F1 and F2 which is the most recent, which can then be used by the two gateways, each for its part, in order to calculate its own priority level. In other words, the selection of the common prioritization function F to be used to calculate the priority level of each of the gateways of the network, comprises the choice by each gateway of the most recent prioritization function from a set of available prioritization functions, on the basis of a time stamp or versioning (that is to say version management) of the formulas or prioritization function in the network. In FIG. 2, this selection is symbolized by the expression F = s {F1, F2} in the double arrow which illustrates the exchange of protocol messages 210 between the gateways GW1 and GW2 of the local network 11.

In an exemplary implementation, the selected prioritization function F is stored by each gateway of the local network 11 for use by said gateway for the calculation of its own priority level on the basis of characteristics specific to said gateway. It can also be transmitted to the other gateways of the local network 11 during a next occurrence of the procedure 21 and of the exchange of protocol messages 210 which it provides for, if necessary.

Then, the procedure 21 continues with the use by each gateway GW1 and GW2 of the prioritization function F selected, to calculate its own priority level P1 and P2, respectively, in step 211 and in step 212, respectively. In FIG. 2, these calculations are symbolized in the bubbles which illustrate steps 211 and 212, by the expressions P1 = F (GW1) and P2 = F (GW2), respectively. These calculations therefore use the same function F on the basis of characteristics specific to each gateway. Thus, the priority levels P1 and P2 which are obtained are truly comparable values.

In an example of nonlimiting implementation, the characteristics specific to each gateway which are taken into account by each gateway of the network, for the calculation of its own priority level, include in particular and in a nonlimiting manner:

- a type of connectivity, for example the fact that it is a wired network, a 3G or 4G-LTE network, a short-range network like Wi-Fi or Bluetooth, etc. ;

- a cost of transporting data per unit of data, expressed for example per kilobyte of data transported;

- a connectivity quality index, for example an average bit error rate, a observed latency time, and / or a transmission rate associated with the considered gateway; etc ...

In general, these characteristics account for the performance of the IP connections established through the gateway concerned in terms of quality of service (QoS), assessed with regard to the transmission rate, the latency, a retransmission rate, etc.

In embodiments, the method comprises an automatic updating of the priority level of at least some of the gateways of the network, and the broadcasting or the transmission by the gateways of their updated priority level, to the objects connected to the local network 11. This makes it possible to adapt, to the evolution of the operating conditions of the gateways, the priority levels respectively associated with the gateways of the local network 11 and which are used by the connected objects of the network as will be explained below.

For example, the automatic updating of the priority level of the gateways of the subnetwork is carried out periodically, at a frequency which is programmable at the level of each gateway, by a new calculation using the same prioritization formula. F as stored at the level of the gateway, but applied to updated values of the characteristics specific to the gateway which are involved in this calculation.

Those skilled in the art will appreciate that the procedure 21 for assigning priority levels can be applied to all or part of the network connection gateways 10 which belong to the local network 11. The assignment procedure 21 can also be implemented in other subnets such as the local network 12, independently of its implementation in the local network 11.

We will now describe the procedure 22 for discovering the gateways of the subnetwork, by the connected objects of the local network 11, which is implemented at least by the connected object loT 1 in accordance with the example shown in the figure 2.

This procedure 22 firstly comprises the broadcasting 220 by the connected object loT 1 of a query message (BCM message, set for "Broadcast Message" in the rectangular arrow symbolizing the broadcasting step 220 in FIG. 2), in the local network 11. This BCM message is then received by the gateways GW1 and GW2 which are connected to the local network 11, as shown in FIG. 1, and also by the other connected objects of the network 11.

In response, the loT1 connected object receives a response message sent by each gateway in the network having received a query message. In addition, the connected object can also receive a response message from other loTs which contains an identifier of said other connected object, as well as a response message sent by each of the gateways of the network 11. Thus, in particular, the message of response 221 returned by the gateway GW1 to the connected object loT1 comprises an identifier of the gateway GW1 (for example its IP address noted @ (GW1) in the arrow symbolizing the message 221 in FIG. 2), on the one hand, and the value of the priority level P1 of the gateway GW1, on the other hand. Likewise, the response message 222 returned by the gateway GW2 to the connected object loT2 comprises an identifier of the gateway GW2 (for example its IP address noted @ (GW2) in the arrow symbolizing the message 222 in FIG. 2 ), on the one hand, and the value of the priority level P2 of the gateway GW2, on the other hand.

The procedure 22 for discovering the local network 11 by the connected object loT 1 then ends with a classification 223, carried out by the connected object loT1, of the gateways of the network in order of their respective priority levels, in view of the choice of a gateway for sending data messages to other connected objects belonging to another or to other subnets connected to the Internet.

Those skilled in the art will appreciate that, once procedures 21 and 22 have been carried out, the architecture of the mesh local area network 11 is known to all the objects connected to said subnetwork. Of course, this procedure can also be implemented in other subnetworks such as the local network 12, independently of its implementation in the local network 11.

We will now describe what happens when the loT1 connected object of the local network 11 sends a data message to another connected object, in this case to the loT2 connected object of the local network 12. This is the exchange procedure 23 of a data message M1 sent by the transmitter connected object loT1 and an acknowledgment message A1 sent back by the recipient connected object after receipt of the message M1.

The M1 data message sent by the loT 1 object can contain:

- a unique identifier of the sender (for example his IP address)

- a unique identifier of the recipient (for example his IP address)

- an application code identifying the application sending the data message sent, and a unique number of the incremented message (in the event of retransmission of the same M1 message);

- application data; as well as preferably,

- the type of message (for example the "data" type in the example considered here);

- its expiration date; and

- a checksum ("Checksum" in English) to validate the integrity of the message transmitted.

Upon receipt of the message M1, the final recipient loT2 transmits the message to the application that it hosts. This application then returns an acknowledgment message A1 to the sender loT1. Acknowledgment message A1 uses the same transport mechanism.

It may contain:

- the identifier of the sender (his IP address in the example);

- the recipient (his IP address in the example);

- the application code and the unique number of the original M1 message; as well as preferably

- its expiration date;

- the type of message, namely "acknowledgment" in this case; and,

- a checksum to validate the integrity of the acknowledgment message A1 transmitted.

Each connected object manages a list of received messages. Thus, if a message already processed by the recipient object loT2 is received again, it is simply acknowledged without further processing.

Unacknowledged messages after the expiration of the expected delivery time are automatically retransmitted by the sending object loT1, and this time is configurable.

Advantageously, the routing of the retransmitted message M1 takes account of a possible update of the mesh of the local network 11 following the loss of connectivity of one or more gateways, for example. This is advantageous because if the non-delivery of the message M1 in the allotted time was caused by a problem at the level of the gateway through which the original message M1 was routed outside the local network 11, then the retransmission of the message M1 can avoid encountering the same problem. In other words, adapting the routing of messages leaving the local network 11 to any change in the connectivity of the available gateways makes it possible to avoid problems linked to a faulty gateway being repeated from one (re) transmission to another. of the message not delivered to the final recipient within the allotted time.

Regarding the routing of each occurrence (when there are several due to retransmission, if any) of the data message M1 in the local network 11 of the transmitter connected object loT1, two should be distinguished. separate cases. These two cases are distinguished according to the classification of the priority levels P1 and P2 of the gateways GW1 and GW2, respectively, which make it possible to establish the connection to the Internet of the connected object transmitting loT1.

Indeed, the data message M1 is transmitted by the transmitter connected object loT1 to that of the Internet connection gateways of the local network 11 which has the highest priority level, with a view to its transmission to the loT2 connected object via the Internet 10. Note that the highest level can correspond to the value of P1 and P2 which is either the lowest or the highest, depending on the prioritization calculation function.

If the gateway GW2 has a priority level P2 higher than the priority level P1 of the gateway GW1 (case P2> P1, represented at the top for the exchange 23 in FIG. 2), the message M1 is transmitted in step 231a to the highest priority gateway GW2. It ultimately reaches the recipient connected object loT2 after transmission over the Internet 10, subject of course to its routing in the allotted time because it can be destroyed when any network equipment (gateway, router) passes if its duration has expired before it reaches the destination. The acknowledgment message A1 returned at 232a by the recipient connected object loT2 to the sender connected object loT1, then takes a connection which can, with regard to access to the local network 11, be the same route by return, i.e. also via the GW2 gateway (as in the example shown), or be another route, depending on the routing algorithms implemented in the Internet network 10. Thus, the fact that access to the Internet 10 is via the gateway GW2 for sending the data message M1 by the transmitting connected object loT1 in no way constrains the establishment of the connection path for the return of the message d 'corresponding acknowledgment A1 from the recipient connected object loT2.

In the opposite case where the gateway GW1 has a priority level P1 higher than the priority level P2 of the gateway GW2 (case P1> P2, represented at the bottom of the exchange 23 in FIG. 2), the message M1 is transmitted in step 231b to the highest priority gateway GW2. It ultimately reaches the recipient connected object loT2 after transmission through the Internet 10. The acknowledgment message A1 sent back in 232b by the recipient connected object loT2 to the sender connected object loT1 then borrows a connection which there still can, with regard to access to the local network 11, be the same route in return, that is to say be done via the gateway GW1 (as in the example shown), or be another route, in function of the routing algorithm implemented in the global network.

Those skilled in the art will appreciate that the transmission of a data message by the transmitter connected object loT1 occurs directly to the recipient connected object, that is to say without passing through any gateway therefore regardless of their respective priority levels, if said recipient connected object belongs to the local network 11. This case is not shown in FIG. 2 because it does not correspond to the implementation of the invention.

In summary, the method according to embodiments of the invention makes it possible to propose:

auto-adaptive message routing, in the sense that it adapts to the connectivity state of all the local network connection gateways that are available, if any, which connectivity state is evolving as it has been exposed;

optimization of message transport costs since, at any time, the gateway used to establish the connection of a connected object from the local network to another object connected via the Internet is the gateway of the local network concerned which has the highest priority in this sense that it offers the best connection characteristics overall; and management of the period of validity of the messages transmitted such as the implementation of protocols in connected mode of the prior art.

Another aspect of the invention relates to a computer program product comprising one or more sequences of instructions stored on a tangible memory medium, readable by a machine comprising a processor, said sequences of instructions being adapted for carry out all the steps of the method of the invention when the program is read from the memory medium and executed by the processor. Another aspect of the invention, again, relates to a tangible recording medium, readable by a computer, storing the program in a non-transient manner.

In this context of the IoT, the invention is presented as a mechanism for transporting the data of a connected object adapted to be connected to a given subnetwork to another connected object belonging to a subnetwork different. This mechanism operates at the layer 4 level of the open systems interface model, or OSI (of the “Open System Interface”), of the International Organization for Standardization or ISO (in English: “International Standard Organization”). ). Layer 4 of the OSI model is the Transport layer, which is the first of the upper layers, directly on top of the three hardware layers: Physical, Link, and Network. Above the Transport layer are the other upper layers, namely, in this order, the Session, Presentation and Application layers.

In this context, one of the main actors for the subnetwork connectivity management method described in the present invention is the gateway. Connection gateways are devices that allow communication, exchange and transport of data between connected objects. A gateway provides the connection between devices on a local network, each associated with a local IP address and main network services associated with public IP addresses. Thus, the same gateway can have at least two IP addresses.

The Internet Protocol (IP) is the standard used by equipment connected to the Internet to communicate with each other. This protocol uses an address (IP address) which allows the identification of the equipment on the network. More generally, an IP address is a unique number assigned to each device connected to a computer network: gateway, computers, smartphones, servers on the Internet providing a service, objects connected to a local network, etc. This address allows individually identify the devices on the network, have them communicate with each other, and connect them to the Internet. There are two types of IP addresses, namely public IP addresses on the one hand and local IP addresses on the other.

Local IP addresses of a wired local IP network of Ethernet type (IEEE 802.3 standard), for example, or of a local wireless IP network of Wi-Fi type (IEEE 802.11a / b / g / standard) n / ac), for example, are managed at the local network level, between the gateway connecting the local network to the Internet, and the equipment (computers, mobiles, connected objects, etc.) belonging to said local network. For example, a modem (i.e., a box) from an Internet service provider (ISP) is an Internet connection gateway that has a specific local IP address by default. Local network user equipment that is connected to the box to access the Internet through said box, has an IP address assigned individually by the box, as do all the objects connected to the local network served by this box. Note that local IP addresses are not present on the Internet because their function is only to allow the exchange of data between the Internet connection gateway and local network equipment.

The IP address uses a specific format defined by the IP protocol. Depending on the format of the Internet Protocol Version 4 (IP v4) protocol, the IP address is made up of 4 groups of decimal digits, each representing a value between 0 and 255, and separated by the symbol "dot" (example: 92.169. 1.25). Thus, the range of IP addresses is potentially from 0.0.0.1 to 255.255.255.255. The IP v4 protocol is used for both local IP addresses and for public IP addresses. Note however that the IP v6 format (Internet Protocol Version 6) is led to succeed the IP v4 format, according to which the IP address is composed of 8 groups of 4 hexadecimal characters, noted from 0 to 9 and from A to F, and separated by the symbol "colon".

Thus, according to another aspect, and as presented in FIG. 3, the invention relates to a connection gateway, preferably to a main network, for the communication of a connected object from a first subnetwork with other connected objects belonging to other subnets also connected to the main network. In particular, the connection gateway according to the invention comprises a prioritization module 1 and a communication module 2.

The prioritization module 1 is advantageously configured to calculate a priority level. Thus, it may include means for selecting, on the basis of exchanges of protocol messages with gateways of the first subnetwork, a common prioritization function to be used to calculate the priority level, and means for calculating its own priority level on the basis of specific characteristics, using the selected prioritization function. As already mentioned, these means can be combinations of processors, random access memory, memory as well as the codes supporting the instructions.

Thus, each gateway can have its own priority level, calculated with the common prioritization function, which makes it possible to obtain values which are comparable with one another to define a priority level.

In particular, the prioritization module is configured to select a most recent common prioritization function.

The communication module 2 is in turn configured to send a response message following the receipt of an interrogation message broadcast by a connected object, said response message comprising an identifier and the priority level of said bridge.

In addition, the prioritization function can be stored by a storage module 3. For this, the storage module can include any readable medium known in the art including, for example, a volatile memory, such a static random access memory (SRAM) and a dynamic random access memory (DRAM), and / or a non-volatile memory, such as read-only memory, flash memories, hard disks, optical disks and magnetic tapes or in the form of a memory volatile, such as random access memory (RAM) and / or cache memory.

According to another aspect, in addition to the gateway, the invention also relates to a connected object as presented in FIG. 3. This connected object, belonging to a first subnetwork comprising several gateways, is suitable for implementing a procedure for discovering and prioritizing the gateways of the first subnetwork.

To this end, it includes a priority access module 4 comprising:

- means for broadcasting a query message 220 in the first subnet

means for receiving a response message 221,222 sent by each of the gateways of the subnetwork, which contains an identifier and the priority level of said gateway; and,

- Means for carrying out a classification 223 of the gateways of the subnetwork in order of their respective priority levels, with a view to choosing a gateway for the transmission of data messages intended for other connected objects belonging to another or other subnets.

In particular, each connected object comprises a priority access module 4 configured to send a BCM type interrogation message which will allow each gateway having received the interrogation message to send the response message to the destination of the priority access module of the connected object. Thus, the priority access module 4 is advantageously configured to send a query message and receive a response message comprising priority levels and IP addresses or identifying gateways. Following this, the classification of the priority levels received by the priority access module 4 allows each connected object to classify each priority level received with a view to choosing a gateway for the transmission of data messages to destination other connected objects belonging to another or to other subnets connected to the main network.

Furthermore, each connected object can include a sending module 5 configured to send a data message when the classification of the priority levels is finished. The data message is sent by a connected object to another connected object through at least one connection gateway.

According to another aspect, the invention relates to a data communication system comprising a subnetwork 11 with connected objects loT 1 and connection gateways GW1, GW2 for the communication of said connected objects with other objects loT2 connected devices belonging to other subnetworks 12. Such a system may in particular consist of an arrangement of the gateways and connected objects according to the invention, described above. In addition, this system is particularly suitable for implementing the method according to the invention.

The present invention has been described and illustrated in the present detailed description and in the figures of the accompanying drawings, in possible embodiments. The present invention is not limited, however, to the embodiments presented. Other variants and embodiments can be deduced and implemented by a person skilled in the art on reading this description and the attached drawings.

As described, the present invention provides solutions for optimized and self-adaptive routing of messages from a connected object, taking into account the state of connectivity of all of the available connection gateways of the sub- network. Thus, unlike the state of the art, the present invention makes it possible in particular to take advantage of the multiplicity of gateways of a subnetwork and of the evolution over time of their connectivity.

Claims (12)

Claims 1. Method for managing a data transport subnetwork (11) which comprises connected objects (loT1) and gateways (GW1, GW2) for the communication of said connected objects with other connected objects (loT2) belonging to other subnetworks (12), said management method comprising: a procedure (21) for assigning priority levels (P1, P2) respectively to gateways (GW1, GW2) of the subnetwork, said procedure for assigning priority levels comprising: • the selection (210), on the basis of exchanges of protocol messages between the gateways of the subnet, of a common prioritization function (F) to be used to calculate the priority level of each of the gateways of the subnet ; and, • the use (211,212) by each gateway of the prioritization function thus selected, to calculate its own priority level (P1, P2) on the basis of characteristics specific to the gateway; as well as : a procedure (22) for discovering the gateways of the subnetwork, by at least one connected object of the subnetwork, said discovery procedure comprising: • the broadcast (220) by the connected object (loT1) of a query message (BCM) in the subnet (11); • the reception (221,222) by the connected object of a response message sent by each of the gateways of the subnet in response to the interrogation message, which contains an identifier of said gateway and the priority level of said gateway; and, • a classification (223) by the connected object of the gateways of the subnetwork in order of their respective priority levels, with a view to the choice of one of said gateways for the transmission of data messages intended for other connected objects belonging to another or to other subnets. 2. Method according to claim 1, characterized in that it further comprises, when a connected object (loT1) of the subnet (11) transmits a data message to another connected object (loT2) which belongs to another subnet (12): the transmission (231 a, 231 b) of the data message (M1) by the transmitting connected object (loT1) to the gateway of the subnet (11) which has the maximum priority level (P1, P2). 3. Method according to one of claims 1 or 2, characterized in that it further comprises an automatic updating of the priority level of at least some of the gateways (GW1, GW2) of the subnetwork (11), and the dissemination or transmission by the gateways of their updated priority level (P) to the connected objects of the subnetwork. 4. Method according to claim 3, characterized in that the automatic updating of the priority level of the gateways (GW1, GW2) of the sub-network (11) is carried out periodically, at a frequency which is programmable at the level of each gateway. 5. Method according to any one of the preceding claims, characterized in that the selection of the common prioritization function (F) to be used to calculate the priority level (P) of each of the gateways (GW1, GW2) of the sub- network (11), includes the choice by each gateway of the most recent prioritization function from a set of available prioritization functions, based on a time stamp or a versioning of the prioritization functions in the subnetwork. 6. Method according to any one of the preceding claims, characterized in that the selected prioritization function is memorized by each gateway of the subnet for use by said gateway for the calculation of its own priority level on the basis of characteristics specific to said gateway. 7. Method according to any one of the preceding claims, characterized in that the characteristics specific to each gateway (GW1, GW2) which are taken into account, by each gateway of the network, for the calculation of its own priority level, include a type of connectivity, a data transport cost per unit of data, a connectivity quality index, a latency time, and / or a transmission rate associated with the network gateway. 8. Method according to any one of the preceding claims, characterized in that the gateways (GW1, GW2) make it possible to connect the sub-network (11) to a main network (10) to which the other sub-networks are connected (12 ). 9. Gateway for the communication of a connected object of a first subnet with other connected objects belonging to other subnets, said connection gateway of the first subnet being characterized in that it comprises : - A prioritization module configured to calculate a priority level of the gateway, and comprising: o means of selection, on the basis of exchanges of protocol messages with other gateways of the first subnetwork, of a common prioritization function to be used to calculate the priority level; and, o means for calculating its own priority level on the basis of characteristics specific to it, using the selected prioritization function; - A communication module configured to send a response message following the reception of an interrogation message broadcast by a connected object of the first subnet as part of a subnet discovery procedure, said message response comprising an identifier of said gateway and the priority level of said gateway. 10. Connected object, adapted to be connected to a first subnetwork comprising several gateways, the connected object being adapted, moreover, to implement a procedure for discovering the first subnetwork and comprising for this purpose a module ( 4) priority access management comprising: - means of broadcasting a query message (220) in the first subnet; - Means for receiving a response message (221,222) sent by each of the subnetwork gateways in response to the interrogation message, which contains an identifier of said gateway and a priority level of said gateway; and, - Means for carrying out a classification (223) of the gateways of the subnetwork in order of their respective priority levels, with a view to choosing one of said gateways for the transmission of data messages intended for other connected objects belonging to another or to other subnets. 11. Data communication system comprising a sub-network (11) with connected objects (loT1) and gateways (GW1, GW2) for the communication of said connected objects with other connected objects (loT2) belonging to others subnets (12), in which: the gateways (GW1, GW2) of the subnetwork (11) are adapted to carry out an assignment procedure (21) of priority levels respectively to each of the gateways of the network, and each includes for this purpose: • means for selecting, on the basis of exchanges of protocol messages (210) between the gateways of the subnetwork, a common prioritization function to be used to calculate the priority level of each of the gateways of the subnetwork; and, • means for calculating one's own priority level on the basis of characteristics 5 specific to each gateway, using the selected prioritization function; and in which: the connected objects of the network are adapted to implement a discovery procedure (22) of the gateways of the subnetwork, and each include for this purpose: • means for broadcasting a query message (220) in the subnetwork; 10 · means for receiving a response message (221,222) sent by each of the gateways of the subnet in response to the query message, which contains an identifier of said gateway and the priority level of said gateway; and, • means for classifying (223) the gateways of the subnetwork in order of their respective priority levels, with a view to choosing a gateway for 15 the transmission of data messages to other connected objects belonging to another or to other subnets.