METHOD FOR MANAGING A LASER DIODE MALFUNCTION

Abstract

The invention relates to a method and a device for managing a malfunction of a laser diode of an optical interface of a user equipment of the ONU type, the user equipment being connected by an optical access network of the passive optical network PON type to a line termination equipment of the OLT type, the user equipment being authorized to transmit an optical signal during a time interval allocated to the user equipment according to a principle of multiple access by time division. According to the invention: - it is checked (E552) whether the laser diode transmits an optical signal outside the allocated time interval and, if so, - a fault is detected (E553), - the deactivation of the laser diode is commanded (E557), - one or more procedures for attempting to correct the fault are executed (E559). Figure to be published with the abstract: Fig. 5a

Description

Title of the invention: METHOD FOR MANAGING A LASER DIODE MALFUNCTION Technical field

[0001] The present invention relates to a method for managing a malfunction of a laser diode in an optical access network of the passive optical network (PON) type, more particularly between an optical line termination device (OLT) and a user device called an optical network unit (ONU). STATE OF PRIOR ART

[0002] The distribution of digital data via an optical access network to a plurality of users, for example to access the Internet, is carried out via a fiber optic medium. This is referred to as FTTH (Fiber To The Home) or FTTB (Fiber To The Building) technology. Thus, several data transport systems can coexist on the same optical fiber, thus enabling a service operator to distribute several services via a reduced infrastructure. Passive optical networks PON can thus be created between one or more OLT optical line termination devices and numerous ONU user equipments, thanks to wavelength coupling devices and user optical line coupling devices.

[0003] The various transport systems correspond to standardized hardware and protocols, for example the G-PON system (“Gigabit Passive Optical Network” in English) which makes it possible to achieve a throughput of 2.5 Gbps in the downstream direction and a throughput of 1.2 Gbps in the upstream direction, as described by the ITU-T G.984 standard, or the XG-PON system (“eXtended Gigabit Passive Optical Network” in English) which makes it possible to achieve a throughput of 10 Gbps in the downstream direction and a throughput of 2.5 Gbps in the upstream direction, as described by the ITU-T G.988 standard, or the XGS-PON system (“10 Gigabit-capable Symmetric Passive Optical Network” in English) which makes it possible to achieve a throughput of 10 Gbps in both the upstream and downstream directions, as described by the ITU-T G.9807.1 standard.

[0004] The different transport systems coexisting on the same optical fiber establish communications by light signals using distinct carrier wavelengths (X) or combs of carrier wavelengths, whether in the uplink or downlink direction.

[0005] In order to ensure the transport of data to a plurality of ONUs connected on a single fiber and whose emission wavelength is identical, the principle of time-division multiple access (TDMA) is implemented. This is a medium access control technique allowing multiple traffic flows to be transmitted on a single channel. It uses a time division of the bandwidth, the principle of which is to distribute the available time between the different users. By this means, a wavelength can be allocated, in turn (almost simultaneously), to several subscribers. Interleaving is done on a set of bits transmitted in predefined time intervals (TS, Time Slot). This multiplexing also makes it possible to transmit synchronous or asynchronous flows over a synchronous link.Since the packets do not necessarily arrive in the order of transmission depending on the paths taken, the role of the demultiplexer is then to reorder them and separate the flows of the different channels in order to restore the information as it was before its transport on the multiplexed network.

[0006] In normal use, the ONU accesses the PON network and transmits its transmission signal during a predefined and dedicated time interval.

[0007] This transmission time window is defined by the OLT for each of the ONUs and transmitted to each of them via the downlink through the GTC (G-PON Traffic Control) messages transmitted at the start of each downlink frame. The ONUs are then required to respect the window allocated to them to transmit their next uplink frame.

[0008] However, it is possible, under so-called fault conditions, for the ONU to transmit its transmission signal either continuously or outside its allocated time interval. This case is known as a "rogue ONU".

[0009] Consequently, these other ONUs are unable to operate normally because they cannot be understood by the OLT. From a user point of view, the impact can range from a simple service disruption to a total interruption of all Internet services (Data, IPTV, voice, etc.).

[0010] In order to ensure quality of service at the network level, it is necessary to detect a rogue ONU type fault and to cut the related transmission signal. Currently, there are methods for detecting and managing rogue ONUs but these are initiated by the OLT. Indeed, the latter integrates a rogue ONU detection mechanism temporarily interrupting the service of all connected ONUs in the event of rogue detection. While the OLT sends an instruction to the faulty ONU to cut its transmission signal and thus restore service for the other ONUs on the port, this nevertheless causes a service disruption. The disadvantage of this current mechanism is that if the faulty ONU restarts, a new disruption occurs.

[0011] It is then desirable to overcome these drawbacks of the state of the art.

[0012] It is particularly desirable to provide a solution that makes it possible to reduce service disruptions for ONUs connected to an optical fiber to which an ONU is connected that emits its transmission signal during a time interval that is not dedicated to it, or even to correct the operation of the ONU so that it emits its transmission signal only during a time interval that is dedicated to it.

[0013] EXPOSE

[0014] A method is proposed for managing a malfunction of a laser diode of an optical interface of a user equipment of the ONU type, the user equipment being connected by an optical access network of the passive optical network PON type to a line termination equipment of the OLT type, the user equipment being authorized to transmit an optical signal during a time interval allocated to the user equipment according to a principle of multiple access by time division, characterized in that the method comprises the following steps, executed by the user equipment, of:

[0015] - checking whether the laser diode emits an optical signal outside the range of time allocated and, if so,

[0016] - detection of a fault,

[0017] - laser diode deactivation command,

[0018] - execution of one or more procedures to attempt to correct the fault.

[0019] One or more embodiments also relate to a device for managing a malfunction of a laser diode of an optical interface of a user equipment of the ONU type, the user equipment being connected by an optical access network of the passive optical network PON type to a line termination equipment of the OLT type, the user equipment being authorized to transmit an optical signal during a time interval allocated to the user equipment according to a principle of multiple access by time division, characterized in that the device is included in the user equipment and comprises:

[0020] - means for verifying whether the laser diode emits an optical signal outside of the allocated time interval and, if so,

[0021] - means for detecting a fault,

[0022] - means for controlling the deactivation of the laser diode,

[0023] - means for executing one or more correction attempt procedures of the fault.

[0024] Thus, according to one or more embodiments, it is possible to reduce service disruptions for ONUs connected to an optical fiber to which an ONU is connected that transmits its transmission signal during a time interval that is not dedicated to it. The gateway implementing one or more embodiments can thus attempt to correct the operation of the ONU so that it transmits its transmission signal. transmission only during a time interval dedicated to it.

[0025] According to a particular embodiment, the verification whether the laser diode emits an optical signal outside the allocated time interval is carried out by comparing a signal delivered by a photodiode included in the optical interface and an activation command of the laser diode emitting optical signals to the line termination equipment, the photodiode being positioned in such a way that it is illuminated by the signal emitted by the laser diode emitting optical signals to the line termination equipment.

[0026] According to a particular embodiment, a first procedure for attempting to correct the fault consists of a reinitialization of a volatile memory used by a driver of the optical interface, a second procedure for attempting to correct the fault consists of a command to load the software used by the driver from the non-volatile memory, and a third procedure for attempting to correct the fault consists of a restart of the user equipment.

[0027] According to a particular embodiment, the second fault correction attempt procedure is executed if the first fault correction attempt procedure has failed and the third fault correction attempt procedure is executed if the second fault correction attempt procedure has failed.

[0028] According to a particular embodiment, the method further comprises a step of transferring a message to the line termination equipment if the fault is detected.

[0029] According to a particular embodiment, the execution of one or more procedures for attempting to correct the fault is conditional on the reception of a message sent by the line termination equipment.

[0030] According to a particular embodiment, the message is transmitted through a logical traffic control communication channel.

[0031] According to a particular embodiment, the message is a notification of a request to put on hold a procedure for banning the user equipment by the line termination equipment.

[0032] Also provided is a computer program, which may be stored on a medium and / or downloaded from a communications network, in order to be read by a processor. This computer program comprises instructions for implementing the method performed by an internet gateway, as mentioned above, when said program is executed by the processor. One or more embodiments also relate to an information storage medium storing such a computer program. Brief description of the drawings

[0033] The above-mentioned features, as well as others, will appear more clearly upon reading the following description of at least one exemplary embodiment, said description being made in relation to the attached drawings, among which:

[0034] [Fig.l] schematically illustrates an optical access network arrangement, in which a particular non-limiting embodiment can be implemented;

[0035] [Fig.2] schematically illustrates an embodiment of user equipment of the optical access network;

[0036] [Fig.3] schematically illustrates an example of a hardware arrangement of a controller of the user equipment of the embodiment of [Fig.2];

[0037] [Fig.4] schematically illustrates a portion of an optical interface of the user equipment of the embodiment of [Fig.2];

[0038] [Fig.5a] schematically illustrates a first example of an algorithm executed by the user equipment;

[0039] [Fig.5b] schematically illustrates a second example of an algorithm executed by the user equipment;

[0040] [Fig.6a] schematically illustrates a first example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it;

[0041] [Fig.6b] schematically illustrates a second example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it;

[0042] [Fig.6c] schematically illustrates a third example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it;

[0043] [Fig.6d] schematically illustrates an example of an algorithm executed when attempts to correct the operation of the UN have failed.

[0044] DETAILED DESCRIPTION OF EMBODIMENTS

[0045] [Fig.l] schematically illustrates an optical access network arrangement, of the PON type, in which one or more embodiments can be implemented.

[0046] The optical access network comprises an OLT 40 G-PON optical line termination equipment as compliant with the ITU-T G.984 standard and an OLT 41 XGS-PON optical line termination equipment as compliant with the ITU-TG.9807.1 standard.

[0047] The OLT 40 G-PON optical line termination equipment transmits an optical signal having a wavelength X2, receives an optical signal having a wavelength XL

[0048] The OLT 41 XGS-PON optical line termination equipment transmits an optical signal having a wavelength X4, receives an optical signal having a wavelength X3.

[0049] The optical access network comprises, for example, N optical network units ONU in [Fig. 1]. In an example of one of the embodiments, an ONU may be included in an internet gateway. In another example of one of the embodiments, an ONU is an individual or autonomous device. This individual device may associate or cooperate with an internet gateway, such as a residential internet gateway, or may cooperate with another device in a network in order to distribute the data received by the OLT there.

[0050] In one example, the optical network unit ONU is included in the internet gateway 10i and complies with the ITU-T G.984 standard, the optical network unit ONU included in the internet gateway 102 complies with the ITU-T G.9807.1 standard, the optical network unit ONU included in the internet gateway 103 complies with the ITU-T G.984 and ITU-T G.9807.1 standards, and the optical network unit ONU 10N is an individual device and complies with the ITU-T G.984 and ITU-T G.9807.1 standards.

[0051] The optical network unit ONU included in the internet gateway 10i transmits an optical signal having a wavelength X1 and receives an optical signal having a wavelength X2, the optical network unit ONU included in the internet gateway 102 transmits an optical signal having a wavelength X3 and receives an optical signal having a wavelength X4.

[0052] The optical network unit ONU included in the internet gateway 103 receives optical signals having a wavelength X4 or X2 and transmits optical signals having a wavelength XI or X3.

[0053] The optical network unit ONU included in the internet gateway 10N receives optical signals having a wavelength X4 or X2 and transmits optical signals having a wavelength XI or X3.

[0054] The optical access network comprises a wavelength coupling device 20 making it possible to couple two other optical lines to the optical fiber 60. These other optical lines allow the optical line termination equipment OLT 40 and 41 to coexist in the optical access network.

[0055] It should be noted here that in certain operating cases, it may be advantageous to combine the equipment 40, 41 and 20 in a combined equipment called OLT combo which supports the overall operation of both G-PON and XGS-PON protocols.

[0056] The optical access network comprises a subscriber line coupling device 30.

[0057] The coupling devices 20 and 30 may for example be switches of WSS (Wavelength Selective Switch) wavelengths adapted to multiplex wavelengths in one direction and demultiplex wavelengths in the opposite direction, or to be simple couplers, because OLTs like ONUs are able to separate the different wavelengths by themselves wavelength. Indeed, being equipped with a monochromatic laser diode and having a selective filter, OLTs like ONUs can only receive signals carried by the wavelength which concerns them.

[0058] [Fig.2] schematically illustrates an embodiment of user equipment of the optical access network.

[0059] The user equipment of the optical access network is for example the ONU included in the internet gateway 103 or is the ONU 10N

[0060] The ONU equipment includes an optical connection not shown in [Fig.2] to which the optical fiber is connected, making it possible to connect the ONU equipment to the rest of the optical access network.

[0061] The ONU equipment further comprises a wavelength multiplexer / demultiplexer MUX making it possible to combine, respectively separate, the optical signals carried by the optical fiber plugged into the optical connector.

[0062] Illustratively, in [Fig. 2], the ONU equipment comprises two branches (220 and 230). Each branch supports a transmission direction (TX) and a reception direction (RX), each having its own carrier wavelength or a comb of own carrier wavelengths.

[0063] Note that the same branch can support several protocols and therefore several transport systems. When several transport systems use the same carrier wavelengths in the optical access network, the use of these carrier wavelengths is shared in time between the transport systems according to a TDMA access time distribution principle.

[0064] Thus, it should also be noted that [Fig.2] represents two branches in an illustrative manner and that the ONU equipment may therefore comprise a different number of branches.

[0065] The ONU equipment comprises a controller 200 which comprises a driver 250 which controls the optical-electrical interfaces 220 and 230.

[0066] Optical-electrical interfaces 220 and 230 each comprising a laser diode (for the TX transmission of optical signals to the OLT) and a photodiode (for the RX reception of signals from the OLT) make it possible to convert optical signals into electrical signals and vice versa.

[0067] According to one embodiment, each optical-electrical interface 220 and 230 further comprises a photodiode which makes it possible to indicate whether the laser diode emits an optical signal as will be described with reference to [Fig.4].

[0068] For example, the optical-electrical interfaces 220 and 230 are structured around components from the company “MACOM” marketed under the name MO2099. These components allow the implementation of a laser diode monitoring mechanism.

[0069] For example, by comparing the transmission request of an optical signal emanating of the controller and the state of the laser diode detected by the photodiode, it is possible to determine whether the laser diode emits an optical signal outside the allocated time interval. The TXSD_A or TXSD_B signal provides the driver 250 with the state detected by the photodiode and the driver 250 or the controller 200 determines whether its laser diode emits an optical signal outside the allocated time interval.

[0070] If transmission activity is detected while the explicit request from the processor is not active, then the laser diode emits an optical signal outside the allocated time interval.

[0071] When the ONU equipment comprises a plurality of branches, the ONU equipment further comprises an electrical signal switch 240. The branch to be used is selected by the controller 200 using a selection line SEL_AB.

[0072] Thus, when branch A is selected by the controller 200 and optical signals are detected in reception on branch A, the optical-electrical interface 220 informs the controller 200 by means of an RXSD_A signal. The electrical signal switch 240 is then configured to route signals present on an RXD_A signal line coming from the optical-electrical interface 220 to the controller 200. In addition, when optical signals are to be transmitted via branch A, the electrical signal switch 240 is configured to route signals present on a TXD signal line coming from the controller 200 to a TXD_A signal line at the input of the optical-electrical interface 220.

[0073] Similarly, when branch B is selected by the controller 200 and optical signals are detected in reception on branch B, the optical-electrical interface 230 informs the controller 200 by means of an RXSD_B signal. The electrical signal switch 240 is then configured to route signals present on an RXD_B signal line from the optical-electrical interface 230 to the RXD signal line. In addition, when optical signals are to be transmitted via branch B, the electrical signal switch 240 is configured to route signals present on the TXD signal line to a TXD_B signal line at the input of the optical-electrical interface 230.

[0074] [Fig. 3] schematically illustrates an example of hardware arrangement of the controller 200. The example of hardware arrangement presented comprises, connected by a communication bus 300: a CPU processor 301; a RAM (Random Access Memory) 302; a ROM (Read Only Memory) 303 or a Flash memory; a storage unit or a storage media reader, such as an SD (Secure Digital) card reader 304 or a HDD (Hard Disk Drive); and at least one set of LO inputs-outputs 305 making it possible in particular to connect the TXD and RXD signal lines.

[0075] The CPU processor 301 is capable of executing instructions loaded into the RAM memory 302 from the ROM memory 303, an external memory (such as an SD card), a storage medium (such as the HDD hard disk), or a communication network (other than the optical access network 100). When the controller 200 is powered up, the CPU processor 301 is capable of reading instructions from the RAM memory 302 and executing them. These instructions form a computer program causing the CPU processor 301 to implement all or part of the behaviors, algorithms and steps described herein.

[0076] Thus, all or part of the algorithms and steps described herein may be implemented in software form by executing a set of instructions by a programmable machine, such as a DSP (Digital Signal Processor) or a microcontroller or a processor. All or part of the algorithms and steps described herein may also be implemented in hardware form by a machine or a component (chip), such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application-Specified Integrated Circuit). Thus, the controller 200 comprises electronic circuitry adapted and configured to implement the behaviors, algorithms and steps described herein.

[0077] [Fig.4] schematically illustrates a portion of an optical interface of the user equipment of the embodiment of [Fig.2].

[0078] As mentioned previously, each optical-electrical interface 220 and 230 comprises a PHT photodiode which makes it possible to indicate whether the laser diode LAS emits an optical signal. The PHT photodiode is positioned such that it is illuminated by the signal emitted by the laser diode LAS.

[0079] [Fig.5a] schematically illustrates a first example of an algorithm executed by the user equipment.

[0080] In step E500, the user equipment initializes the variable noted Diag_timing to the zero value and the variable noted Diag_mode to the value “OFF”.

[0081] In step E501, the user equipment launches the verification procedure if each laser diode LAS emits an optical signal only in the predefined and dedicated time interval and sets the variable Detect_timing to the zero value.

[0082] In step E502, the user equipment compares the signal TXSD_A or TXSD_B with the request to activate the laser diode LAS coming from the controller 200.

[0083] For example, when the TXSD_A or TXSD_B signal is high, the LAS laser diode emits an optical signal.

[0084] If the signal TXSD_A or TXSD_B is at the high level in a time interval different from the activation time interval of the laser diode LAS requested by the controller 200, the laser diode emits an optical signal outside the allocated time interval and a fault is detected.

[0085] In step E503, the user equipment checks whether a fault is detected.

[0086] If a fault is detected, the user equipment goes to step E504. In the negative, the user equipment goes to step E507.

[0087] In step E504, the user equipment commands the deactivation of the laser diode for which the fault was detected.

[0088] In step E505, the user equipment checks whether the signal TXSD_A or TXSD_B is at the low level, i.e. whether the laser diode is not emitting an optical signal.

[0089] If yes, the user equipment proceeds to step E506. If no, the user equipment interrupts the present algorithm.

[0090] In step E506, the user equipment commands the execution of one or more procedures for attempting to correct the fault and sets the variable Diag_mod to the value “ON”.

[0091] In step E507, the user equipment checks whether the variable Diag_mod is at the value “ON” and whether the value of the variable Detect_timing is greater than the value of the variable Diag_timing. This check indicates whether a fault correction attempt was successful.

[0092] If no, it was not necessary to make a fault correction attempt. If yes, a fault correction attempt was successful and the user equipment proceeds to step E508.

[0093] In step E508, the user equipment interrupts the fault correction attempt procedure and sets the variable Diag_timing to the value zero and the variable noted Diag_mode to the value “OFF”. In a particular mode, the user equipment stores an identifier of the fault correction attempt which makes it possible to correct the fault in the event of executing it as a priority if a new fault were to be detected later. The user equipment then returns to step E501.

[0094] [Fig.5b] schematically illustrates a second example of an algorithm executed by the user equipment.

[0095] In step E550, the user equipment initializes the variable noted Diag_timing to the value zero and the variable noted Diag_mode to the value “OFF”.

[0096] In step E551, the user equipment launches the verification procedure if each laser diode LAS emits an optical signal only in the predefined and dedicated time interval and sets the variable Detect_timing to the zero value.

[0097] In step E552, the user equipment compares the signal TXSD_A or TXSD_B with the request to activate the laser diode LAS coming from the controller 200.

[0098] For example, when the TXSD_A or TXSD_B signal is high, the LAS laser diode emits an optical signal.

[0099] If the signal TXSD_A or TXSD_B is at the high level in a time interval different from the activation time interval of the laser diode LAS requested by the controller 200, the laser diode emits an optical signal outside the allocated time interval and a fault is detected.

[0100] In step E553, the user equipment checks whether a fault is detected.

[0101] If a fault is detected, the user equipment proceeds to step E554. In the negative, the user equipment goes to step E560.

[0102] In step E554, the user equipment commands the sending of a message to the line termination equipment of the type to which it is connected.

[0103] The user equipment sends for example a specific PON message to the line termination equipment to which it is connected via the GTC (G-PON Traffic Control) logical communication channel in order to notify that a laser fault is detected and that the user equipment launches the execution of attempts to correct the fault.

[0104] The uplink GTC logical communication channel is still active in the vast majority of cases because, quite generally, the data transmission function works correctly, but the driver is unable to cut off the optical signal transmission outside the time window. The user equipment transmits the PON message in the time window allocated to it.

[0105] In the minority of cases where the fault is more serious, the line termination equipment will not be able to understand the specific message being transmitted.

[0106] For example, in the case of the G-PON protocol based on the ITU-T G.984.3 standard, it is possible for the ONU to communicate control information to the OLT by means of the PLOAM messages defined in chapter 9 of the ITU-T G.984.3 standard. The upstream Physical_Equipment_Error (PEE) message (code 0x06) is an example of a message that can be used to signal to the line termination equipment a malfunction.

[0107] The arguments of the upstream Physical_Equipment_Error message, in particular bytes 3 to 12, include a specific value highlighting the characteristic of the error diagnosed by the user equipment and being the subject of an attempt to correct it.

[0108] The transferred message is for example a simple preventive notification and a temporary hold of the banning procedure conventionally implemented by the line termination equipment. For example, the message includes a predetermined identifier between OxOA and OxFF and having as an argument a processing time by the user equipment of the attempt to correct the fault, for example, in the form of a duration in seconds from which the user equipment will attempt to communicate again, at the risk of causing a new error.

[0109] In step E555, the user equipment checks whether a message rejecting the attempt fault correction is received from the line termination equipment of the type to which it is connected.

[0110] If so, the user equipment goes to step E556 and commands the deactivation of the laser diode for which the fault was detected. If not, the user equipment goes to step E557.

[0111] In step E557, the user equipment commands the deactivation of the laser diode for which the fault was detected.

[0112] In step E558, the user equipment checks whether the signal TXSD_A or TXSD_B is at the low level, i.e. whether the laser diode is not emitting an optical signal.

[0113] If yes, the user equipment proceeds to step E559. If no, the user equipment interrupts this algorithm.

[0114] In step E559, the user equipment commands the execution of one or more procedures for attempting to correct the fault and sets the variable Diag_mod to the value “ON” as described with reference to Figs. 6a to 6d.

[0115] For example, the order of execution of the procedures for attempting to correct the fault is the execution first of [Fig.6a], then in the event of failure to correct the fault the execution of [Fig.6b], then in the event of failure to correct the fault, the execution of [Fig.6c], then in the event of failure to correct the fault the execution of [Fig.6d].

[0116] It should be noted here that the order of execution of the fault correction attempt procedures is modifiable and / or that only a part of the fault correction attempt procedures as described with reference to Figs. 6a to 6d is executed.

[0117] In step E560, the user equipment checks whether the variable Diag_mod is at the value “ON” and whether the value of the variable Detect_timing is greater than the value of the variable Diag_timing. This check indicates whether a fault correction attempt was successful.

[0118] If no, no fault correction attempt was necessary. If yes, a fault correction attempt was successful and the user equipment proceeds to step E561.

[0119] In step E561, the user equipment interrupts the fault correction attempt procedure and sets the variable Diag_timing to the value zero and the variable noted Diag_mode to the value “OFF”. In a particular mode, the user equipment stores an identifier of the fault correction attempt which makes it possible to correct the fault in the event of executing it as a priority if a new fault were to be detected later. The user equipment then returns to step E551.

[0120] [Fig.6a] schematically illustrates a first example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it.

[0121] The user equipment executes this algorithm when the variable Diag_mod has the value “ON” and the variable Diag_name is not at the value “STACK” or “BACKUP” or “REBOOT”.

[0122] In step E600, the user equipment commands a reset of the PON protocol layer control component (for example G-PON and / or XGS-PON and / or XG-PON etc.) used by the pilot 250. This PON protocol layer control component may be a software component, or a hardware component, or a mixture of software and hardware elements, coupled with the PON interface.

[0123] In step E601, the user equipment authorizes activation of the laser diode in the time interval dedicated to the user equipment, sets the variable Diag_timing to the value 300, sets the value of the variable Diag_name to the value “STACK”. The value 300 is decremented every second and when the value of the variable Diag_timing is zero, the user equipment returns to step E502 or E552.

[0124] [Fig.6b] schematically illustrates a second example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it.

[0125] The user equipment executes this algorithm when the variable Diag_mod is at the value “ON” and the variable Diag_name is at the value “STACK”.

[0126] In step E610, the user equipment commands the loading of the software used by the driver 250 from the non-volatile memory.

[0127] In step E611, the user equipment commands a reset of the control component of the PON protocol layer used by the pilot 250.

[0128] In step E612, the user equipment authorizes activation of the laser diode in the time interval dedicated to the user equipment, sets the variable Diag_timing to the value 300 and sets the value of the variable Diag_name to the value “CONFIG”. The value 300 is decremented every second and, when the value of the variable Diag_timing is zero, the user equipment returns to step E502 or E552.

[0129] [Fig.6c] schematically illustrates a third example of an algorithm for attempting to correct the operation of the ONU so that it emits its transmission signal only during a time interval dedicated to it.

[0130] The user equipment executes this algorithm when the variable Diag_mod is at the value “ON” and the variable Diag_name is at the value “CONFIG”.

[0131] In step E620, the user equipment commands a restart thereof.

[0132] In step E621, the user equipment commands an initialization of the component of piloting the PON protocol layer used by the 250 driver.

[0133] In step E622, the user equipment authorizes activation of the laser diode in the time interval dedicated to the user equipment, sets the variable Diag_timing to the value 300 and sets the value of the variable Diag_name to the value "REBOOT". The value 300 is decremented every second and, when the value of the variable Diag_timing is zero, the user equipment returns to step E502 or E552.

[0134] [Fig.6d] schematically illustrates an example of an algorithm executed when attempts to correct the operation of the ONU have failed.

[0135] The user equipment executes this algorithm when the variable Diag_mod is at the value “ON” and the variable Diag_name is at the value “REBOOT”.

[0136] In step E630, the user equipment considers that the attempts to correct the fault have failed, stores information indicating that each attempt has failed and generates information representative of the operating fault of the optical link via a human-machine interface of the internet gateway.

Claims

Claims

1. Method for managing a malfunction of a laser diode of an optical interface of a user equipment of the ONU type, the user equipment being connected by an optical access network of the passive optical network PON type to a line termination equipment of the OLT type, the user equipment being authorized to transmit an optical signal during a time interval allocated to the user equipment according to a principle of multiple access by time division, characterized in that the method comprises the following steps, executed by the user equipment, of: - checking (E552) whether the laser diode transmits an optical signal outside the allocated time interval and, if so, - detecting (E553) a fault, - controlling (E557) the deactivation of the laser diode, - executing (E559) one or more procedures for attempting to correct the fault.

2. Method according to claim 1, characterized in that the verification that the laser diode emits an optical signal outside the allocated time interval is carried out by comparing a signal delivered by a photodiode included in the optical interface and an activation command of the laser diode emitting optical signals to the line termination equipment, the photodiode being positioned in such a way that it is illuminated by the signal emitted by the laser diode emitting optical signals to the line termination equipment.

3. Method according to claim 1 or 2, characterized in that a first procedure for attempting to correct the fault consists of a reinitialization of a volatile memory used by a driver of the optical interface of a PON protocol layer control component, a second procedure for attempting to correct the fault consists of a command to load the software used by the driver from the non-volatile memory, and a third procedure for attempting to correct the fault consists of a restart of the user equipment.

4. Method according to claim 3, characterized in that the second procedure of attempting to correct the fault is executed if the first procedure of attempting to correct the fault has failed and the third fault correction attempt procedure is performed if the second fault correction attempt procedure failed.

5. Method according to any one of claims 1 to 4, characterized in that the method further comprises a step of transferring a message to the line termination equipment if the fault is detected.

6. Method according to claim 5, characterized in that the execution of one or more procedures for attempting to correct the fault is conditional on the reception of a message sent by the line termination equipment.

7. Method according to claim 5 or 6, characterized in that the message is transmitted through the logical traffic control communication channel.

8. Method according to claim 7, characterized in that the message is a notification of a request to put on hold a procedure for banning the user equipment by the line termination equipment.

9. Computer program product comprising instructions for implementing, by a processor, the method according to any one of claims 1 to 8, when said program is executed by said processor.

10. An information storage medium storing a computer program comprising instructions for implementing, by a processor, the method according to any one of claims 1 to 8, when said program is read and executed by said processor.

11. Device for managing a malfunction of a laser diode of an optical interface of a user equipment of the ONU type, the user equipment being connected by an optical access network of the passive optical network PON type to a line termination equipment of the OLT type, the user equipment being authorized to transmit an optical signal during a time interval allocated to the user equipment according to a principle of multiple access by time division, characterized in that the device is included in the user equipment and comprises: - means for verifying whether the laser diode transmits an optical signal outside the allocated time interval and, if so, - means for detecting a fault, - means for controlling the deactivation of the laser diode, - means for executing one or more attempt procedures correction of the fault.

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