Method for detecting a loss of signal of a local network between a home gateway and at least one device, home gateway and associated computer program product.

Abstract

Method for detecting a loss of signal of a local network between a home gateway (10) and at least one device (1 to 9), the home gateway (10) being connected to an operator network (WAN) via a wired connection and to at least one device (1 to 9) via a local network (LAN), the method comprising the following steps: - measuring the quality of the signal of the local network between said home gateway (10) and the at least one device (1 to 9) at initialization of the home gateway (10), - measuring the current quality of the local network signal between said home gateway (10) and the at least one device (1 to 9), - calculating a measurement difference value between the measurement of the current signal quality and the measurement of the signal quality at initialization of the home gateway (10), the measurement difference value making it possible to detect whether the connection between the home gateway (10) and the at least one device (1 to 9) is broken.Figure for abstract: Fig. 1.

Description

Title of the invention: Method for detecting a loss of signal of a local network between a home gateway and at least one peripheral, home gateway and associated computer program product. Technical field

[0001] The present invention relates to a method for measuring signal quality between a home gateway and at least one peripheral. It also relates to a home gateway and an associated computer program product. State of the prior art

[0002] Devices and systems related to the Internet of Things (IoT) are known, in particular those using private networks and radio exchanges for communication. Devices and systems related to the Internet of Things frequently integrate sensitive components, such as door locks, opening detectors, motion detectors, digital codes, cameras, as well as security systems that rely on these IoT components for example.

[0003] The risk of this type of device or system is that a frequency jammer can potentially interrupt the connection between the various elements of the system, for example between the home gateway and the sensors / actuators or between a repeater and a device. Current frequency jammers can also cut the internet connection (in the case of a radio connection). The risks associated with such communication cuts are therefore numerous, ranging from the non-detection of openings or closings to the prevention of alerts being triggered, or even the non-receipt or non-recording of images from surveillance cameras, for example.

[0004] The invention therefore aims to resolve at least one of the problems cited above by a new method for measuring the quality of the signal between a domestic gateway and at least one peripheral.

[0005] Another object of the present invention is to solve at least one problem of vulnerability of a connection between a home gateway and a device via a new home gateway. Statement of the invention

[0006] This objective is achieved with a method for detecting a loss of signal of a local network between a home gateway and at least one device, the home gateway being connected to an operator network via a wired connection and to at least a device via a local network, the method comprising the following steps:

[0007] - measuring the quality of the local network signal between said home gateway and at least one device at the initialization of the home gateway,

[0008] - measure the current local network signal quality between said gateway do mestic and at least one peripheral,

[0009] - calculating a measurement difference value between the signal quality measurement current and the measurement of the signal quality at initialization of the home gateway (10), the measurement difference value making it possible to detect whether the connection between the home gateway (10) and the at least one device (1 to 9) is cut.

[0010] In the present invention, the home gateway which is physically connected to the operator network via a fiber optic or copper connection for example, therefore not subject to jamming, makes it possible to detect the risks of jamming by a malicious person. The connection between the home gateway and the operator network cannot therefore be jammed or cut via this type of device since the connection is wired.

[0011] The quality of the signal between the home gateway and a device in the user's home is measured in real time and compared to an initial measurement, making it possible to detect whether a connection is cut after a period T of use. By "cut" is meant the fact that the quality of the signal is partially reduced or completely stopped or very low compared to the quality of the signal at the initialization of the home gateway. In this case, the user can be warned that a malicious operation is in progress, for example via the use of a frequency jammer or that the device in question is broken. By "signal quality" is meant a value corresponding to the power of the transmitted signal.

[0012] Advantageously, the method may further comprise a step of comparing the measurement difference value with a predetermined threshold, the connection between the home gateway and the at least one peripheral being cut off if the measurement difference value exceeds a predetermined threshold. The measurement difference value, i.e. the difference between the two measurements, is compared with a predetermined threshold. The measurement of the quality of a signal is defined between a maximum value and a minimum value, the maximum value being defined by a regulation, for example European regulation. The minimum value corresponds to the value below which it is impossible to transmit data. For example, for the WIFI protocol (2.4 Ghz) the maximum value is -30 db and the minimum value is -67 db. In the case of this example, at -80 db the connection is possible, but data exchanges are impossible and at -90 db the connection is impossible.

[0013] If, when the home gateway is initialized, the signal strength is between the minimum and maximum values, the channel is considered usable. Gene- Typically, the channel manager chooses the channel with the most power and the lowest occupancy (number of devices using the channel).

[0014] When using a device within the user's home, if the power of the channel used by the device in question falls below its minimum value, and if the protocol supports channel change, the system tries to select another channel. If another channel can be used, no alert is issued. Otherwise, i.e. if no other channel can be used, the connection is considered to be cut off. In the case where the protocol does not support a channel change, the connection is also considered to be cut off.

[0015] Alternatively, the connection is considered to be broken if the signal power of a channel drops by a significant difference without falling below the minimum power value. For example, a significant drop corresponds to a drop between -5 and -15 db. This range of values ​​can be adjustable.

[0016] Advantageously, the predetermined threshold can be adjusted dynamically according to the evolution of the signal quality during a period of time T1. Indeed, the signal quality can be influenced by the weather or by a metallic object such as a car or by the neighbor's network. There is also the possibility that the batteries of the device weaken over time or vary according to the temperature, which will affect the signal quality. The dynamic adjustment therefore makes it possible to remedy at least one of these drawbacks. Preferably, the period of time T1 is between fifteen minutes and two hours.

[0017] The local network signal quality measurements can be carried out on at least one of the following protocols: - wireless communication protocols according to the IEEE 802.11 group standards; - protocols based on IEEE 802.15.4 group standards; - wireless protocols according to the IEEE 802.15.4 group standards; - radio protocols concerning the 868 MHz frequency band.

[0018] Wireless communication protocols according to the standards of the IEEE 802.11 group concern, more generally, the WIFI network. Protocols based on the standards of the IEEE 802.15.4 group concern, more generally, the “Zigbee” type network. Wireless protocols according to the standards of the IEEE 802.15.4 group concern more generally the “Thread” type network. And finally, radio protocols concerning the 868 MHz frequency band concern, more generally, the “Zwave” type network.

[0019] Advantageously, the peripherals in the user's home are located on the frequencies belonging to these protocols, for example, mainly the 2.4 GHz frequency band.

[0020] An alert may be sent to the user if the connection between the home gateway and the at least one device is cut. This makes it possible to notify the user or directly a security operator that a connection problem has been identified between the home gateway and one of the devices in the user's home.

[0021] The method may further comprise:

[0022] - periodic communication of the domestic gateway with at least one peripheral spherical according to a time period T2.

[0023] Preferably, the time period T2 is between 1 and 15 minutes for example.

[0024] This makes it possible to monitor whether the connection of a device to the local network disappears completely and to warn the user or the security operator. "Communication" means that a request is sent to the at least one device so that it responds to it in order to check whether the communication between the two is effective.

[0025] In addition, in order to minimize the impact on the battery of certain devices that these periodic communications may have, communications outside of "periodic communication" may be taken into account. For example, if the device communicates with the home gateway in normal times, these communications will be taken into account. If the home gateway sends commands, these communications will be taken into account. Since each type of device does not require the same level of security, this time period value T2 may be adjustable depending on the device or the type / family of device.

[0026] For example, a door opening sensor may be checked more regularly than a thermostatic radiator valve. For devices that may go into standby for a longer or shorter period of time, which could be interpreted as a problem, the time period T2 is longer, or even unmonitored.

[0027] According to yet another aspect of the invention, there is provided a home gateway comprising a processing unit configured to implement a method according to the invention.

[0028] According to yet another aspect of the invention, there is provided a computer program product comprising instructions which, when the program is executed by a processing unit, cause the latter to implement the method according to the invention. Description of the figures and embodiments

[0029] Other advantages and particularities of the invention will appear on reading the detailed description of implementations and embodiments which are in no way limiting, and the following appended drawings:

[0030] [Fig.l] illustrates an example of topology of a system comprising the invention installed in a user's home,

[0031] [Fig.2] illustrates a schematic representation of an example of a gateway do mestic according to the invention.

[0032] These embodiments being in no way limiting, it will be possible in particular to consider variants of the invention comprising only a selection of characteristics described or illustrated subsequently isolated from the other characteristics described or illustrated (even if this selection is isolated within a sentence comprising these other characteristics), if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention compared to the state of the prior art. This selection comprises at least one preferably functional characteristic without structural details, and / or with only a part of the structural details if this part only is sufficient to confer a technical advantage or to differentiate the invention compared to the state of the prior art.

[0033] Generally, each home is equipped with a home gateway. The home gateway is placed in the user's living room, for example. The home gateway is connected to an operator network (WAN) via a wired connection, for example, by optical fiber or ADSL or copper wire. The home gateway is also connected to one or more devices placed in the user's home via a local network. The connection of the various devices in the home with the home gateway via the local network is either wired or wireless.

[0034] We will first describe, with reference to [Fig.l], an example of topology of a system comprising the invention installed in a user's home. The system comprises a home gateway 10 connected to a WAN operator network in a wired manner, for example via optical fiber or ADSL cable. The home gateway 10 is connected to several peripherals 1 to 9 via a LAN local area network. The different peripherals 1 to 9 are positioned in the user's home according to his needs. For example, there is an alert button 1, a door opening sensor 2, a connected door lock 3, a thermostat 4, a connected car gate 5, three repeaters 6 to 8 and a connected camera 9. According to an embodiment given as an example, the different peripherals 1 to 5 and 8 to 9 are connected to the home gateway 10 via the local area network wirelessly on different radio frequencies.The radio frequencies are of the Zigbee type, for example 2.4 GHz, Thread, for example 2.4 GHz, Zwave, for example between 800 and 900 MHz, or WIFI, for example 2.4 GHz or 5 GHz or 6 GHz. The two repeaters 6 and 7 are, for example, connected wired via an Ethernet cable or via a PLC powerline socket. The connection between the home gateway 10 and all the devices 1 to 9 is therefore heterogeneous. The method for detecting a loss of signal. according to the invention is implemented by the home gateway 10 in this embodiment but can also be implemented by a device external to the home gateway 10 in other embodiments such as for example: a security center, a multimedia box of the STB “set up box” type, a router or a repeater.

[0035] Firstly, the quality of the local network signal is measured between the home gateway 10 and the devices 1 to 9 installed in the home when the home gateway 10 is initialized. That is to say, during the first connection or the first use of the home gateway 10, the quality of the local network signal between the home gateway 10 and each device 1 to 9 is measured. The signal quality measurement is therefore made on the different radio frequencies used by the different devices 1 to 9.

[0036] In a second step, the quality of the current local network signal is measured between said home gateway 10 and the devices 1 to 9 installed in the home. The quality of the signal is then measured at a time T of use of the gateway, T corresponding to a period of time of use after the initialization of the home gateway 10.

[0037] Finally, the measurement of the current signal quality is compared to the measurement of the signal quality at the initialization of the home gateway 10. Preferably, the measurement difference value, i.e. the difference between the two measurements, must not exceed a predetermined threshold. The difference exceeds the predetermined threshold, for example, if the signal of the monitored frequency band disappears completely or in part or if there is a significant degradation of the signal.

[0038] Optionally, in the case where a signal quality measurement between the home gateway 10 and one of the peripherals 1 to 9 can no longer be measured following the disappearance of the peripheral 1 to 9 in the system, an alarm is triggered only if no other channel is available in the frequency band used and the disturbance persists after a period of time T, for example equal to two minutes. This period of time is adjustable according to the need. Indeed, since a given frequency band is divided into several channels, “no channel available” means that, in the case where a peripheral uses one of the channels of the frequency band in question and another user installs a more powerful peripheral than the peripheral at the user's home, for example, said peripheral can no longer communicate on this channel.Therefore, the user's home device tests the next channel and so on until it finds one free to communicate. An alarm is therefore triggered if all channels in the frequency band used are unavailable.

[0039] If the signal quality between the home gateway 10 and the connected door lock 3 exceeds the predetermined threshold, the user or security operator receives an alert indicating that a potential risk of intrusion or that a potential lock failure has been detected.

[0040] According to the embodiments, the predetermined threshold is adjusted dynamically according to the evolution of the quality of the signal measured between the home gateway 10 and one of the peripherals 1 to 9 over time, according to a time period T1 which, for example, corresponds to every fifteen minutes. This time period is adjustable according to the need.

[0041] For even more security, the home gateway 10 is configured to communicate periodically with one or more devices 1 to 9 according to a time period T2. Indeed, the home gateway 10 is configured to regularly send, according to the time period T2, a request to the device 1 to 9. The device 1 to 9 is configured to also respond to it via a request. This double verification makes it possible to further secure the user's system since this second verification makes it possible to verify whether the device 1 to 9 can still communicate via the local LAN network with the home gateway 10. This function can also be performed by a device external to the home gateway 10 in other embodiments such as for example: a security center, a multimedia box of the STB "set up box" type, a router or a repeater when one of these devices is configured to implement the method according to the invention..

[0042] We will now describe, with reference to [Fig.2], a schematic representation of an example of a home gateway according to the invention. The home gateway 10 is connected to a WAN operator network by wire, for example via optical fiber or ADSL cable. The home gateway 10, according to one embodiment, comprises a WIFI module 11, a Zigbee module 12, a Z-Wave module 13, a Thread module 14, an Ethernet module 15, a jammer detector 16 and a data bus 17. The home gateway 10 may also comprise other modules 18 according to the embodiments. These other modules 18 correspond for example to known modules of this type of system such as for example an loT rule manager module and / or a television management module for a multimedia box of the “set up box” type. The jammer detector 16 is configured to implement the method according to the invention.The different modules 11 to 15 are configured to measure the signal quality of the frequency band corresponding to each of them. Each signal measurement of each module is then sent to the data bus 17. The data bus transfers all of the data received by the different modules 11 to 15 to the jammer detector 16 which is configured to analyze and process them. That is to say, a first measurement of the signal quality at the initialization of the home gateway 10 is carried out by the . different modules 11 to 15 between the home gateway 10 and the different devices installed in the user's home. In a second step, the current local network signal quality is measured between said home gateway 10 and the devices installed in the home by the different modules 11 to 15. The jammer detector 16 is configured to compare the two signal measurements for each device and determine whether the connection between said device and the home gateway 10 is cut by comparing the difference between the two measurements with a predetermined threshold. In the event that a cut connection is detected, the jammer detector 16 is configured to send an alarm to a security operator 19 via the operator WAN network.

[0043] Typically at least one of the means of the device according to the invention previously described, preferably each of the means of the device according to the invention previously described are technical means.

[0044] Typically, each of the means of the device according to the invention previously described may comprise at least one computer, a central or computing unit and / or a microprocessor (preferably dedicated), and / or software means.

[0045] Of course, the invention is not limited to the examples which have just been described and numerous adjustments can be made to these examples without departing from the scope of the invention.

[0046] Of course, the various features, forms, variants and embodiments of the invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive. In particular, all the variants and embodiments described above may be combined with each other.

Claims

Claims

1. A method for detecting a loss of signal of a local network between a home gateway (10) and at least one device (1 to 9), the home gateway (10) being connected to an operator network (WAN) via a wired connection and to at least one device (1 to 9) via a local network (LAN), the method comprising the following steps: - measuring the quality of the signal of the local network between said home gateway (10) and the at least one device (1 to 9) at initialization of the home gateway (10), - measuring the current quality of the local network signal between said home gateway (10) and the at least one device (1 to 9), - calculating a measurement difference value between the measurement of the current signal quality and the measurement of the signal quality at initialization of the home gateway (10),the measurement difference value for detecting whether the connection between the home gateway (10) and the at least one device (1 to 9) is broken.,

2. A detection method according to claim 1, the method further comprising a step of comparing the measurement difference value with a predetermined threshold, the connection between the home gateway (10) and the at least one device (1 to 9) being cut off if the measurement difference value exceeds a predetermined threshold.

3. Detection method according to claim 2, wherein the predetermined threshold is dynamically adjusted according to the evolution of the quality of the signal during a period of time T1.

4. Detection method according to any one of the preceding claims, wherein the local network signal quality measurements can be carried out on at least one of the following protocols: - wireless communication protocols according to the standards of the IEEE 802.11 group; - protocols based on the standards of the IEEE 802.15.4 group; - wireless protocols according to the standards of the IEEE 802.15.4 group; - radio protocols relating to the 868 frequency band MHz.

5. A detection method according to any preceding claim, wherein an alert is sent to the user if the connection between the home gateway (10) and the at least one device (1 to 9) is cut.

6. Detection method according to any one of the preceding claims, further comprising: - periodic communication of the home gateway (10) with the at least one peripheral (1 to 9) according to a time period T2.

7. A home gateway comprising a processing unit configured to implement a method according to any one of claims 1 to 6.

8. Computer program product comprising instructions which, when the program is executed by a processing unit, cause the latter to implement the method according to any one of claims 1 to 6.

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