PON system time synchronization method and device based on Combo FTTR and storage medium

Abstract

The invention provides a PON system time synchronization method and device based on Combo FTTR and a storage medium. The method comprises the following steps: receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is connected with the first interface of the OLT and the PON MAC of the ONU; the second physical channel is connected with the second interface of the OLT and the PON MAC of the ONU; according to the detected time synchronization working state of the first physical channel, whether a target time correction value is a first time correction value or a second time correction value is determined, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; and clock synchronization of the ONU and the OLT is carried out based on the target time correction value, so that dual-physical-channel main and standby protection switching of time synchronization is realized, the problem of time service quality reduction caused by a fault of a single physical channel is avoided, and the accuracy of time synchronization is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber communication technology, and in particular to a PON system time synchronization method, device and storage medium based on Combo FTTR. Background Art

[0002] In order to meet the requirements of fiber to the room (FTTR) equipment being compatible with optical line terminal (OLT) ports of different standards, and to meet the requirements of broadband network upgrade without interruption of user services and without replacement of FTTR equipment, the Combo FTTR solution can be used. Combo FTTR can flexibly configure the uplink interface working mode of the FTTR main equipment according to network deployment and service SLA requirements, that is, it can be compatible with three types of passive optical network (PON) interfaces at the local end: Gigabit-capable PON (GPON), asymmetric 10-Gigabit hybrid passive optical network (10-Gigabit-capable Combo PON, XG Combo PON) and symmetric 10-Gigabit hybrid passive optical network (10-Gigabit-capable Symmetric Combo PON, XGS Combo PON).

[0003] However, the existing Combo FTTR only has the time synchronization capability of a single physical channel. When the physical channel fails or degrades, the timing quality will decrease and the accuracy of time synchronization cannot be guaranteed. Summary of the invention

[0004] The present invention provides a PON system time synchronization method, device and storage medium based on Combo FTTR, which are used to solve the technical problem in the prior art that the accuracy of the PON system time synchronization of Combo FTTR cannot be guaranteed.

[0005] In a first aspect, the present invention provides a PON system time synchronization method based on Combo FTTR, comprising the following steps.

[0006] Receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT with a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT with the PON MAC of the ONU; Determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The clocks of the ONU and the OLT are synchronized based on the target time correction value.

[0007] In some embodiments, determining the target time correction value according to the detected time synchronization working state of the first physical channel includes: When it is detected that the time synchronization working state of the first physical channel is normal, determining the target time correction value to be the first time correction value; and / or In the case where it is detected that the time synchronization working state of the first physical channel is abnormal, a target time correction value is determined according to the detected time synchronization working state of the second physical channel.

[0008] In some embodiments, determining the target time correction value according to the detected time synchronization working state of the second physical channel includes: When it is detected that the time synchronization working state of the second physical channel is normal, the target time correction value is determined to be the second time correction value.

[0009] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal and when it is detected that the time synchronization working state of the second physical channel is normal, time synchronization tracking is performed through the second physical channel.

[0010] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel and the time synchronization working state of the second physical channel are both abnormal, a fault report is performed.

[0011] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal, the time synchronization working state of the first physical channel is continuously detected, and a target time correction value is determined according to the detected time synchronization working state of the first physical channel.

[0012] In some embodiments, when the first power-on startup is completed, the method further includes: When the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal, reporting a fault; and / or When the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal, it is determined whether there is a time synchronization function abnormality in the first physical channel and / or the second physical channel based on the first time correction value and the second time correction value.

[0013] In some embodiments, judging whether the first physical channel and / or the second physical channel has a time synchronization function abnormality based on the first time correction value and the second time correction value includes: Determining whether a difference between the first time correction value and the second time correction value is within a preset range; When the difference between the first time correction value and the second time correction value is within a preset range, determining that there is no time synchronization function abnormality in the first physical channel and / or the second physical channel; and / or When the difference between the first time correction value and the second time correction value is not within a preset range, it is determined that a time synchronization function abnormality exists in the first physical channel and / or the second physical channel.

[0014] In some embodiments, the method further comprises: When the difference between the first time correction value and the second time correction value is within a preset range, performing clock synchronization between the ONU and the OLT according to the first time correction value, and performing time synchronization tracking through the first physical channel; and / or; When the difference between the first time correction value and the second time correction value is not within a preset range, a fault report is performed.

[0015] In some embodiments, the performing clock synchronization between the ONU and the OLT based on the target time correction value includes: When the target time correction value is less than a preset threshold, the time counter of the ONU is corrected using the target time correction value; When the target time correction value is greater than or equal to a preset threshold, the time counter of the ONU is gradually corrected based on the target time correction value.

[0016] In some embodiments, the stepwise correction of the time counter of the ONU based on the target time correction value includes: Within a preset control time interval, the time counter of the ONU is corrected N times; the value of each correction is equal to 1 / N of the target time correction value.

[0017] In some embodiments, the first physical channel and the second physical channel use the same optical fiber path, and the optical transceiver device of the first physical channel and the optical transceiver device of the second physical channel are independent of each other.

[0018] In a second aspect, the present invention provides a PON system time synchronization device based on Combo FTTR, comprising the following modules.

[0019] The first determination module is used to receive the first time synchronization information through the first physical channel and receive the second time synchronization information through the second physical channel; the first physical channel is used to connect the first interface of the optical line terminal OLT and the passive optical network media access control PON MAC; the second physical channel is used to connect the second interface of the OLT and the PON MAC; A second determination module is used to determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is the first time correction value or the second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The synchronization module is used to synchronize the clocks of the ONU and the OLT based on the target time correction value.

[0020] In some embodiments, the second determining module includes: A first determining submodule is configured to determine, when detecting that the time synchronization working state of the first physical channel is normal, that the target time correction value is the first time correction value; and / or The second determining submodule is used to determine a target time correction value according to the detected time synchronization working state of the second physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal.

[0021] In some embodiments, the second determining submodule includes: The first determining unit is configured to determine that the target time correction value is the second time correction value when it is detected that the time synchronization working state of the second physical channel is normal.

[0022] In some embodiments, it also includes: The synchronization tracking module is used to perform time synchronization tracking through the second physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal and the time synchronization working state of the second physical channel is normal.

[0023] In some embodiments, it also includes: The first fault reporting module is used to report a fault when it is detected that the time synchronization working state of the first physical channel and the time synchronization working state of the second physical channel are both abnormal.

[0024] In some embodiments, it also includes: The detection module is used to continuously detect the time synchronization working state of the first physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal, and determine the target time correction value according to the detected time synchronization working state of the first physical channel.

[0025] In some embodiments, it also includes: A second fault reporting module is used to report a fault when the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal; and / or A judgment module is used to judge whether there is a time synchronization function abnormality in the first physical channel and / or the second physical channel based on the first time correction value and the second time correction value when the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal.

[0026] In some embodiments, the determination module includes: A judging submodule, used for judging whether the difference between the first time correction value and the second time correction value is within a preset range; A third determining submodule is configured to determine that there is no time synchronization function abnormality in the first physical channel and / or the second physical channel when the difference between the first time correction value and the second time correction value is within a preset range; and / or The fourth determining submodule is used to determine that a time synchronization function abnormality exists in the first physical channel and / or the second physical channel when the difference between the first time correction value and the second time correction value is not within a preset range.

[0027] In some embodiments, the following also include: a synchronization unit, configured to perform clock synchronization between the ONU and the OLT according to the first time correction value when the difference between the first time correction value and the second time correction value is within a preset range, and perform time synchronization tracking through the first physical channel; and / or; The fault reporting unit is used to report a fault when the difference between the first time correction value and the second time correction value is not within a preset range.

[0028] In some embodiments, the synchronization module includes: A first correction submodule, configured to correct the time counter of the ONU using the target time correction value when the target time correction value is less than a preset threshold; The second correction submodule is used to gradually correct the time counter of the ONU based on the target time correction value when the target time correction value is greater than or equal to a preset threshold.

[0029] In some embodiments, the second correction submodule includes: The time correction unit is used to correct the time counter of the ONU N times within a preset control time interval; the value of each correction is equal to 1 / N of the target time correction value.

[0030] In some embodiments, the first physical channel and the second physical channel use the same optical fiber path, and the optical transceiver device of the first physical channel and the optical transceiver device of the second physical channel are independent of each other.

[0031] In a third aspect, the present invention provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the PON system time synchronization method based on Combo FTTR as described in the first aspect above is implemented.

[0032] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the Combo FTTR-based PON system time synchronization method as described in the first aspect above.

[0033] In a fifth aspect, the present invention further provides a computer program product, including a computer program, wherein when the computer program is executed by a processor, the Combo FTTR-based PON system time synchronization method as described in the first aspect above is implemented.

[0034] The present invention provides a Combo FTTR-based PON system time synchronization method, device and storage medium, wherein an ONU receives first time synchronization information through a first physical channel and receives second time synchronization information through a second physical channel, wherein the first physical channel is used to connect a first interface of an optical line terminal OLT and a passive optical network media access control PONMAC of the ONU, and the second physical channel is used to connect a second interface of the OLT and the PON MAC of the ONU; a target time correction value is determined to be the first time correction value or the second time correction value according to the detected time synchronization working state of the first physical channel; clock synchronization of the ONU and the OLT is performed based on the target time correction value, thereby realizing dual physical channel active-standby protection switching of time synchronization, avoiding the problem of timing quality degradation caused by a single physical channel failure, and ensuring the accuracy of time synchronization. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 This is a schematic diagram of the current FTTR network architecture.

[0037] Figure 2 This is a schematic diagram of the current Combo FTTR implementation principle.

[0038] Figure 3 This is a schematic diagram of the physical channel for time synchronization transmission within the current PON system.

[0039] Figure 4 This is a schematic diagram of the physical channel for time synchronization transmission within the current Combo FTTR-based PON system.

[0040] Figure 5 It is a flow chart of a PON system time synchronization method based on Combo FTTR provided by the present invention.

[0041] Figure 6 It is a schematic diagram of the implementation principle of the dual-channel Combo FTTR provided by the present invention.

[0042] Figure 7 The present invention provides a flow chart of a Combo FTTR single-fiber dual-physical channel master-slave time synchronization method.

[0043] Figure 8It is a schematic diagram of the state judgment mechanism of the Combo FTTR single-fiber dual-physical channel time synchronization primary and standby switching provided by the present invention.

[0044] Fig. 9 It is a flow chart of the time synchronization phase jump control method provided by the present invention.

[0045] Fig.10 It is a schematic diagram of the implementation principle of the time synchronization phase jump control provided by the present invention.

[0046] Fig.11 It is a structural schematic diagram of a PON system time synchronization device based on Combo FTTR provided by the present invention.

[0047] Fig.12 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0048] At present, mature commercial Combo ports are XG Combo PON ports and XGS Combo PON ports. In both ports, there are two independent channels, namely GPON channel and 10G PON channel. The advantage of this is that Combo PON port allows GPON ONU and 10G PON ONU to be connected at the same time, which has good compatibility and is also conducive to a smoother upgrade from GPON in the existing network to 10G PON. The implementation principle itself is relatively simple, that is, using the difference in working wavelengths of different PON systems, using wavelength division multiplexing to allow them to be combined into the same optical fiber and work simultaneously, and the wavelength division multiplexing function is realized through optical devices such as traditional thin film filters or multi-layer coated folding reflectors. Commercial Combo PON ports usually integrate wavelength division multiplexing optical devices directly into a single optical module to achieve a compact equipment layout.

[0049] Figure 1 This is a schematic diagram of the current FTTR network architecture. Figure 1As shown in the figure, the basic idea of ​​FTTR is to further extend the optical fiber to the end user on the basis of fiber to the home (FTTH) and fiber to the office (FTTO), so as to provide fiber coverage inside the customer premises (for example, home or office). The FTTR main equipment, namely the fiber to the room main equipment (Main FTTR unit, MFU), and the FTTR slave equipment in each room, namely the fiber to the room slave equipment (Sub FTTR unit, SFU) are connected by optical fiber. The FTTR main equipment is the core of the FTTR network. It connects to the OLT to provide FTTH access to the home, and provides optical ports to connect to the FTTR slave equipment through P2MP (point to multipoint) to form the FTTR network.

[0050] Combo FTTR (i.e. Combo MFU) is compatible with OLT ports of different standards, which can avoid the need for installation and maintenance to visit and replace FTTR equipment twice when the network is upgraded from GPON to 10G PON. In terms of user experience, Combo FTTR can complete the network upgrade to 10G PON without the user being aware of it.

[0051] The implementation principle of Combo FTTR is similar to that of Combo PON. It combines wavelength division multiplexing devices and electronic switches. Figure 2 This is a schematic diagram of the current Combo FTTR implementation principle, such as Figure 2 As shown in the figure, the uplink interface of Combo FTTR (i.e., the interface connecting Combo FTTR main device and central office OLT) contains two physical channels of GPON and 10G PON at the same time, but the signal flow of these two physical channels can enter the PON MAC chip for processing only through a two-choice electronic switch. In this way, at a certain moment, Combo FTTR either works on the 10G PON physical channel or on the GPON physical channel. Combo FTTR has the automatic detection and adaptive working ability of the uplink interface. When the uplink interface of Combo FTTR is connected to the OLT GPON PON port, it will choose to work on the GPON physical channel; when the uplink interface of Combo FTTR is connected to the OLTXG-PON port or the OLT XGS-PON port, it will choose to work on the 10G PON physical channel. Through this operation process, Combo FTTR can realize automatic compatibility and adaptability to various types of uplink central office OLT PON ports.

[0052] Currently, the time synchronization technologies widely used in communication networks include NTP (Network Time Protocol), IEEE1588V2 (Precise Time Synchronization Protocol), ITU-T G.8275.1 (Precise Time Synchronization Protocol for Communication Networks), etc. These technologies are generally used outside the PON system. Inside the PON system, rooted in the architectural characteristics of the PON system itself, a unique high-precision time synchronization transmission and distribution technology is adopted, which does not rely on two consecutive timestamp exchanges between the master and the slave, and does not follow the common IEEE 1588V2 protocol master-slave synchronization method. This method originated from the ITU-TG.984.3 Amendment2 technical specification in November 2009. It achieves a time synchronization tracking accuracy of ±1 microsecond while consuming less system resources and not interfering with the transmission of business data streams. In the ITU-T G.9807.1 technical specification, this method is slightly optimized.

[0053] In commercial networks, the time synchronization outside the PON system and the time synchronization inside the PON system must be connected. Simply put, the OLT is responsible for tracking the upper-level time source through protocols such as IEEE 1588, and then distributing the time synchronization information to each ONU through internal mechanisms. The ONU then notifies protocols such as IEEE 1588 to pass the time synchronization information to the service equipment.

[0054] The time synchronization transmission and distribution process within the PON system is as follows: First, it is assumed that the OLT itself has an accurate time source (in commercial networks, this is usually achieved by having the OLT track a superior time source, and the tracking method is often that the OLT runs the IEEE 1588V2 protocol and interacts with the previous protocol node to synchronize protocol data packets). At this time, any specified ONU (denoted as ONUi) needs to synchronize with the OLT time source (that is, the OLT needs to transmit and distribute its own time information to the downstream ONUi).

[0055] Secondly, the OLT selects the start position of a physical frame of the downstream PON transmission convergence layer (GTC) to be sent within the next 10 seconds as the time synchronization reference point. This frame is recorded as frame N (the value of N is marked by the superframe counter in the downstream frame header). The OLT calculates a time value corresponding to the frame and records it as TstampN (this time value is represented as the precise time when the frame arrives at the hypothetical ONU, but in fact it is the reference time obtained by adding a period of offset from the time TsendN actually sent by the OLT). Then the OLT sends N and TstampN to ONUi in advance through the optical network unit management and control interface (OMCI). After receiving the frame, ONUi stores the values.

[0056] Again, based on its known RspTimei (ONUi response time, which is a fixed value between 34 and 36 microseconds known to ONUi after it is activated online and works normally) and EqDi value (ONUi Assigned equalization delay, which is the assigned value notified to ONUi by OLT through messages after ONUi is activated online and works normally), ONUi can calculate the offset of the time when ONUi actually receives frame N relative to TstampN, which is recorded as Δi. TstampN is the value stored in the previous step. In this way, ONUi uses TstampN and Δi as the medium, and finally calculates the precise time when it will actually receive frame N based on TsendN as the time reference. This precise time is recorded as TrecvNi, and ONUi stores the value of this time to prepare for time calibration in advance.

[0057] Finally, OLT sends frame N at TsendN as expected, and ONUi is always decoding and comparing the superframe count indication byte of each downstream GTC on the line until ONUi receives frame N as expected later. At the moment of receiving frame N, ONUi immediately sets its own time to the value TrecvNi stored in the previous step. In this way, the entire synchronization process between ONUi and the OLT time source is completed within the PON system.

[0058] Figure 3 This is a schematic diagram of the physical channel for time synchronization transmission within the current PON system, such as Figure 3As shown in the figure, the PON time synchronization physical channel is directly based on the existing precise ranging, ONU delay measurement, upstream frame header alignment, downstream GTC superframe counting, upstream time slot dynamic allocation, OMCI control information transmission channel and other mechanisms in the PON protocol layer. A time synchronization physical channel is established point-to-point between the OLT and each ONU, and the synchronization operation of the ONU tracking the internal time source of the OLT is completed as needed. The time synchronization physical channel is completely consistent with the physical path of the PON optical signal transmission. If the PON optical path protection technology is not adopted (such as trunk optical fiber protection switching, full optical fiber protection switching, etc., most systems in commercial PON networks do not adopt optical path protection technology), then in the internal section of an independent PON port (from the OLT sending optical port to the ONU receiving optical port), this time synchronization physical channel is unique. Moreover, for the OLT Combo PON port, although the port can simultaneously hang multiple different types of ONUs, for each specific ONU, its time synchronization physical channel is still unique, and there will not be multiple time synchronization physical channels at the same time.

[0059] Figure 4 This is a schematic diagram of the physical channel for time synchronization transmission within the current Combo FTTR-based PON system. Figure 4 As shown in the figure, if the Combo FTTR type ONU is considered, analysis shows that for each specific Combo FTTR in its actual state, its time synchronization physical channel is still unique at any time, and there will not be multiple time synchronization physical channels at the same time. The difference between Combo FTTR and ordinary ONU in terms of time synchronization physical channel is that if it is connected to the OLT Combo PON port, its time synchronization physical channel can be changed as needed, so that different time synchronization physical channels are selected accordingly in different working modes.

[0060] Therefore, without configuring Type B protection or Type C protection, the existing Combo FTTR only has the time synchronization capability of a single physical channel, that is, for each of the multiple optical network units (ONUs) hanging under the Combo PON port, its time synchronization physical channel is unique. However, the Combo FTTR itself has the ability to work on the GPON and 10G PON channels and obtain time synchronization information, and this capability is idle and wasted on the existing Combo FTTR.

[0061] Moreover, before and after the Combo FTTR working state is switched, the actual clock traceability relationship has not changed, but the received ToD time message path has changed because the physical channel for receiving time synchronization transmission has switched. Although the ToD time message is transmitted through different optical wavelengths and different logical ports in the same optical fiber, it will be transmitted through different optical wavelengths and different logical ports (these differences will produce additional time calculation errors), and the interactive calculation process will be re-performed on the new time synchronization physical path. After completing this interactive calculation process, the Combo FTTR will correct its own clock according to the calculation results, and due to the existence of additional errors, this correction process will cause the time synchronization phase jump before and after its switching.

[0062] Based on the above technical problems, the present invention proposes a PON system time synchronization method based on Combo FTTR, wherein a first time correction value is determined through time synchronization information received through a first physical channel, and a second time correction value is determined through time synchronization information received through a second physical channel, wherein the first physical channel is used to connect a first interface of an optical line terminal OLT and a passive optical network media access control PON MAC of an ONU, and the second physical channel is used to connect a second interface of the OLT and the PON MAC of the ONU; a target time correction value is determined according to the detected time synchronization working state of the first physical channel; clock synchronization of the ONU and the OLT is performed based on the target time correction value, thereby realizing active-standby protection switching of dual physical channels for time synchronization, avoiding the problem of timing quality degradation caused by a single physical channel failure, and ensuring the accuracy of time synchronization.

[0063] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] Figure 5 FIG. 1 is a flow chart of a PON system time synchronization method based on Combo FTTR provided by the present invention, such as Figure 5 As shown, the present invention provides a PON system time synchronization method based on Combo FTTR, and the execution subject thereof may be an ONU, specifically a Combo FTTR ONU. The method comprises: Step 501, receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT and a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT and the PON MAC of the ONU.

[0065] Specifically, in the embodiment of the present application, based on the existing design of the Combo FTTR ONU, no new hardware capacity is added, and the hardware electronic switch is modified to a dual-channel connection. The first physical channel is used to connect the first interface of the optical line terminal OLT and the passive optical network media access control (PON Media Access Control, PON MAC) of the ONU, and the second physical channel is used to connect the second interface of the OLT and the PON MAC of the ONU.

[0066] The first interface of the OLT may be an OLT XG-PON port or an OLT XGS-PON port, and the second interface of the OLT may be an OLT GPON PON port. In this case, the first physical channel (i.e., the 10G PON physical channel) is used as the main physical channel, and the second physical channel (i.e., the GPON physical channel) is used as the backup physical channel.

[0067] For example, Figure 6 FIG. 1 is a schematic diagram of the implementation principle of the dual-channel Combo FTTR provided by the present invention, such as Figure 6 As shown, the PON MAC chip capacity of the Combo FTTR ONU can meet the requirements of simultaneous processing of GPON and 10G PON data streams, and the embodiment of the present application only needs to simultaneously process synchronous related data streams with very low bandwidth, so the hardware capacity of the original design can meet the needs and no additional hardware capacity is required.

[0068] In some embodiments, the first physical channel and the second physical channel use the same optical fiber path, and the optical transceiver device of the first physical channel and the optical transceiver device of the second physical channel are independent of each other.

[0069] Specifically, the first physical channel and the second physical channel pass through exactly the same optical fiber path, that is, there is no difference in terms of pigtail length, ONU internal processing time, or chip processing flow.

[0070] After the dual-path connection is established, the ONU receives time synchronization information through the first physical channel (i.e., the main physical channel) and the second physical channel (i.e., the backup physical channel) respectively.

[0071] Step 502: determine a target time correction value based on the detected time synchronization working status of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information.

[0072] Specifically, the time synchronization working status of the first physical channel is monitored in real time, and a target time correction value is determined according to the detected time synchronization working status of the first physical channel. The target time correction value is used for the final time synchronization adjustment. Determining the target time correction value means determining whether the value ultimately used to adjust the ONU's own time is the first time correction value or the second time correction value.

[0073] The first time correction value is calculated based on the first time synchronization information received by the first physical channel, and the second time correction value is calculated based on the second time synchronization information received by the second physical channel.

[0074] Step 503: Perform clock synchronization between the ONU and the OLT based on the target time correction value.

[0075] Specifically, after the target time correction value is determined, the clock synchronization between the ONU and the OLT is performed based on the target time correction value, that is, the clock of the ONU itself is corrected based on the target time correction value to achieve the clock synchronization between the ONU and the OLT.

[0076] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application determines a first time correction value through time synchronization information received through a first physical channel, and determines a second time correction value through time synchronization information received through a second physical channel, determines a target time correction value according to the detected time synchronization working state of the first physical channel, and performs clock synchronization of the ONU and the OLT based on the target time correction value, thereby realizing that dual physical channels for time synchronization are online at the same time, and can select a final time correction value according to the time synchronization working state of the physical channel, thereby avoiding the problem of decreased timing quality caused by a failure of a single physical channel, and ensuring the accuracy and effectiveness of time synchronization.

[0077] In some embodiments, determining the target time correction value according to the detected time synchronization working state of the first physical channel includes: When it is detected that the time synchronization working state of the first physical channel is normal, determining the target time correction value to be the first time correction value; and / or In the case where it is detected that the time synchronization working state of the first physical channel is abnormal, a target time correction value is determined according to the detected time synchronization working state of the second physical channel.

[0078] Specifically, the time synchronization working status of the first physical channel and the second physical channel is monitored in real time. When the time synchronization working status of the first physical channel is normal, the first physical channel is used for time synchronization tracking, and the first time correction value is used as the target time correction value. When the time synchronization working status of the first physical channel is abnormal, it is necessary to further judge the time synchronization working status of the second physical channel and determine the target time correction value.

[0079] The Combo FTTR ONU will complete the time synchronization message reception and synchronization tracking calculation through the GPON physical channel and the 10G PON physical channel at the same time. However, the ONU's own clock is only corrected according to the calculation results of the primary physical channel (10G PON channel) to maintain accurate tracking of the OLT time source.

[0080] For example, Figure 7 FIG. 1 is a flow chart of a Combo FTTR single-fiber dual-physical channel master-slave time synchronization method provided by the present invention, such as Figure 7 As shown, in the master state, that is, when it is detected that the time synchronization working states of the first physical channel and the second physical channel are both normal, the Combo FTTR performs synchronization tracking through the first physical channel (i.e., the 10G PON physical channel). At the same time, the Combo FTTR maintains the operation of the synchronization mechanism of the second physical channel (i.e., the GPON physical channel), but does not perform synchronization tracking according to the calculation result of the second physical channel (i.e., the second time correction value).

[0081] When a synchronization failure occurs in the primary physical channel, the secondary physical channel (backup physical channel) is switched to for synchronization tracking.

[0082] For example, Figure 7 As shown in Figure 1, when the 10G PON physical channel fails, the Combo FTTR switches to the backup physical channel (GPON channel) for synchronization tracking. Due to the failure of the 10G PON physical channel, the Combo FTTR no longer maintains the operation of the 10G PON channel synchronization mechanism, but monitors its failure status.

[0083] In the embodiment of the present application, before performing the active / standby switching, it is also necessary to determine whether the calculation result of the standby physical channel is available according to the time synchronization working status of the second physical channel.

[0084] In some embodiments, determining the target time correction value according to the detected time synchronization working state of the second physical channel includes: When it is detected that the time synchronization working state of the second physical channel is normal, the target time correction value is determined to be the second time correction value.

[0085] Specifically, after determining that the time synchronization working status of the first physical channel is abnormal, if it is detected that the time synchronization working status of the second physical channel is normal, it means that the second time correction value currently calculated according to the time synchronization information received by the second physical channel is valid and available. At this time, the second time correction value is used as the target time correction value.

[0086] In the Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application, the ONU can switch to the backup physical channel (the second physical channel) and re-correct the ONU's own clock according to the synchronization calculation result of the backup physical channel, so as to maintain accurate tracking of the OLT time source in the event of a main channel failure.

[0087] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal and when it is detected that the time synchronization working state of the second physical channel is normal, time synchronization tracking is performed through the second physical channel.

[0088] Specifically, when it is determined that the time synchronization working state of the first physical channel is abnormal and it is detected that the time synchronization working state of the second physical channel is normal, in addition to using the second time correction value as the target time correction value, time synchronization tracking is also performed through the second physical channel to realize switching from the main physical channel to the backup physical channel.

[0089] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel and the time synchronization working state of the second physical channel are both abnormal, a fault report is performed.

[0090] Specifically, after determining that the time synchronization working state of the first physical channel is abnormal, if it is detected that the time synchronization working state of the second physical channel is also abnormal, a fault is reported.

[0091] In some embodiments, the method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal, the time synchronization working state of the first physical channel is continuously detected, and a target time correction value is determined according to the detected time synchronization working state of the first physical channel.

[0092] Specifically, when it is detected that the time synchronization working state of the first physical channel is abnormal, the ONU still maintains the state monitoring of the main physical channel (the first physical channel) so as to timely discover the recovery of the synchronization failure of the main physical channel.

[0093] For example, when it is detected that the time synchronization working state of the first physical channel is abnormal, and the time synchronization working state of the second physical channel is normal, the ONU switches the active and standby physical channels, corrects the ONU's own clock according to the second time correction value, and performs time synchronization tracking through the second physical channel. After the active and standby switching, when the ONU detects that the time synchronization working state of the first physical channel has returned to normal, the active use of the physical channel is restored, and the currently calculated time correction value of the first physical channel is used as the target time correction value to correct the ONU's own clock, thereby returning to a normal state.

[0094] like Figure 7 As shown in the figure, when the ONU detects that the synchronization function of the main physical channel has returned to normal, the Combo FTTR switches back to the 10G PON channel for synchronization tracking. The Combo FTTR continues to maintain the operation of the GPON channel synchronization mechanism, but no longer performs synchronization tracking based on the channel calculation result (the second time correction value).

[0095] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application uses the calculation result of the main physical channel to perform synchronization tracking in a normal state. When the main physical channel fails, it can switch to the backup physical channel and use the calculation result of the backup physical channel to perform synchronization tracking. When the main physical channel is monitored to be restored to normal, it switches back to the main physical channel for synchronization tracking. The dual physical channels of time synchronization are online at the same time, and the final time correction value can be selected according to the time synchronization working state of the physical channel, avoiding the loss of synchronization or the decrease of accuracy caused by the failure of a single physical channel, and ensuring the accuracy and effectiveness of time synchronization.

[0096] In some embodiments, when the first power-on startup is completed, the method further includes: When the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal, reporting a fault; and / or When the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal, it is determined whether there is a time synchronization function abnormality in the first physical channel and / or the second physical channel based on the first time correction value and the second time correction value.

[0097] Specifically, after the Combo FTTR is powered on for the first time and started up, the ONU determines the time synchronization working state of the first physical channel and the second physical channel. If the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal, a fault report is performed.

[0098] For example, Figure 8 FIG. 1 is a schematic diagram of a state judgment mechanism for time synchronization of a Combo FTTR single-fiber dual-physical channel active / standby switching provided by the present invention. Figure 8 As shown in the figure, after the first power-on startup of the Combo FTTR is completed, check whether the time synchronization working state of the first physical channel (i.e., the 10GPON physical channel) is normal, and record the time correction value △T10G (i.e., the first time correction value). If the time synchronization working state of the first physical channel is abnormal, report the fault; if the time synchronization working state of the first physical channel is normal, check whether the time synchronization working state of the second physical channel (i.e., the GPON physical channel) is normal, and record the time correction value △TG (i.e., the second time correction value). If the time synchronization working state of the second physical channel is abnormal, report the fault; if the time synchronization working state of the second physical channel is normal, proceed to the next step.

[0099] It should be noted that there is no prescribed time sequence for determining the time synchronization working status of the first physical channel and the second physical channel in the initial stage.

[0100] If the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal, it is further determined whether there is a time synchronization function abnormality in the first physical channel or the second physical channel.

[0101] For example, determine whether the first time correction value and the second time correction value are basically synchronized. If they are basically synchronized, it indicates that the time synchronization function is normal and the next step can be performed; if the first time correction value and the second time correction value differ greatly, it indicates that the time synchronization function is abnormal and the fault needs to be reported.

[0102] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application needs to check the time synchronization working status of the first physical channel and the second physical channel at the initial stage, i.e. after the first power-on, to ensure that the two physical channels can be used normally to avoid being put into operation with faults. And based on the first time correction value and the second time correction value, it is judged whether there is an abnormality in the time synchronization function of the physical channel, which further reduces the synchronization error and avoids being put into operation with faults.

[0103] In some embodiments, judging whether the first physical channel and / or the second physical channel has a time synchronization function abnormality based on the first time correction value and the second time correction value includes: Determining whether a difference between the first time correction value and the second time correction value is within a preset range; When the difference between the first time correction value and the second time correction value is within a preset range, determining that there is no time synchronization function abnormality in the first physical channel and / or the second physical channel; and / or When the difference between the first time correction value and the second time correction value is not within a preset range, it is determined that a time synchronization function abnormality exists in the first physical channel and / or the second physical channel.

[0104] Specifically, in the initial stage, when judging whether the physical channel has a time synchronization function abnormality, it is possible to judge whether the difference between the first time correction value and the second time correction value is within the preset range in combination with the preset range, thereby obtaining a conclusion on whether the time synchronization physical channel (including the first physical channel and the second physical channel) has a time synchronization function abnormality. The preset range is a normal error range between the time correction values ​​of two physical channels preset according to actual experience or demand.

[0105] When the difference between the first time correction value and the second time correction value is within the preset range, it indicates that the difference between the first time correction value and the second time correction value is small, and the time synchronization can be determined to be normal. When the difference between the first time correction value and the second time correction value exceeds the preset range, it indicates that the difference between the first time correction value and the second time correction value is large, and the time synchronization can be determined to be abnormal.

[0106] For example, Figure 8 As shown, the preset range is 0 to △Tnormal. If the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal, the difference in the time correction values ​​of the single-fiber dual physical channels (i.e., |△T10G-△TG|) is compared to see whether it is less than △Tnormal. If |△T10G-△TG|<△Tnormal, it indicates that the time synchronization function of the dual physical channels is normal. If |△T10G-△TG|≥△Tnormal, it indicates that the time synchronization function of the dual physical channels is abnormal.

[0107] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application compares the time synchronization calculation results of the primary and backup physical channels in combination with a preset range to determine whether the time synchronization functions of the two physical channels are normal, so that the physical channels are troubleshooted before performing the primary and backup time synchronization of the single-fiber dual-physical channels, thereby ensuring the normal operation of the primary and backup physical channels.

[0108] In some embodiments, the method further comprises: When the difference between the first time correction value and the second time correction value is within a preset range, performing clock synchronization between the ONU and the OLT according to the first time correction value, and performing time synchronization tracking through the first physical channel; and / or; When the difference between the first time correction value and the second time correction value is not within a preset range, a fault report is performed.

[0109] Specifically, Figure 8 As shown, when the difference between the first time correction value and the second time correction value is within the preset range, the time correction instruction of the first physical channel (i.e., the main physical channel) is executed, the time correction value is the first time correction value (△T10G), and the work is set to perform synchronous tracking on the first physical channel (i.e., the main physical channel). At the same time, the normal operation of the time synchronization mechanism of the second physical channel (backup physical channel) is maintained, but the correction instruction of the second physical channel is not executed.

[0110] Then execute the Combo FTTR single-fiber dual-physical channel master-slave time synchronization process: monitor the time synchronization working status of the first physical channel and the second physical channel in real time, determine whether the synchronization tracking of the first physical channel fails (that is, determine whether the time synchronization working status of the first physical channel is normal). If there is no failure, continue to use the first physical channel for synchronization tracking, and use the first time correction value as the target correction value; if a failure occurs, determine whether the synchronization mechanism of the second physical channel (backup physical channel) works normally. If there is an abnormality, report the fault. If normal, switch to the second physical channel for time synchronization tracking, and keep monitoring the time synchronization mechanism of the first physical channel. Once the first physical channel resumes normal time synchronization working status, switch to the first physical channel for time synchronization tracking.

[0111] When the difference between the first time correction value and the second time correction value is not within a preset range, a fault report is performed.

[0112] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application, if it is detected that the error between the time synchronization calculation results of the primary and standby physical channels is large at the initial stage, the fault is reported in time, and if the error is within the preset range, the primary and standby physical channels are used to perform time synchronization. The availability of the primary and standby physical channels is guaranteed, the synchronization error is reduced, and the operation with faults is avoided, thereby ensuring the accuracy of time synchronization.

[0113] In some embodiments, the performing clock synchronization between the ONU and the OLT based on the target time correction value includes: When the target time correction value is less than a preset threshold, the time counter of the ONU is corrected using the target time correction value; When the target time correction value is greater than or equal to a preset threshold, the time counter of the ONU is gradually corrected based on the target time correction value.

[0114] Specifically, in a short period of time before and after the main switch to the backup or the backup switch to the main, the ONU's own crystal oscillator clock will not change significantly, and the OLT's built-in time source will not change significantly. Therefore, if after switching to another physical channel, the result calculated according to its time synchronization mechanism is that the ONU's own clock should be corrected to a large extent (that is, a large phase jump occurs), then the essential reason is not that the ONU's own crystal oscillator clock suddenly has a large error, but the additional error introduced by the ToD mechanism itself on the new physical channel. At this time, if the ONU's own clock is corrected immediately according to the time synchronization calculation result on the new physical channel, it is not reasonable, and it will have an adverse effect on the timing performance of the terminal service equipment.

[0115] In the embodiment of the present application, the target time correction value is judged by using a preset threshold value. If the target time correction value is less than the preset threshold value, it indicates that the amplitude of the time correction is small and a large phase jump will not occur. The target time correction value can be directly used to correct the ONU time counter. However, if the target time correction value is greater than or equal to the preset threshold value, it indicates that the amplitude of the time correction is large and a large phase jump will occur. At this time, the ONU time counter needs to be corrected step by step, that is, the target time correction value is divided into multiple parts, and a point is corrected each time until the target time correction value is adjusted.

[0116] For example, Fig. 9 FIG. 1 is a flow chart of a time synchronization phase jump control method provided by the present invention, such as Fig. 9 As shown, after the master-slave switching (including master-slave switching and backup-slave switching) of the time synchronization physical channel is completed, the normal calculation process of time synchronization tracking is completed on the new physical channel, and the correction value △Tx (i.e., the target time correction value) in the time correction instruction is obtained and saved, but the instruction is not executed temporarily. Further, it is determined whether △Tx is less than the preset threshold value Tnormal. If △Tx is less than the preset threshold value Tnormal, the time correction instruction is executed to correct the time counter of the ONU itself; if △Tx is greater than or equal to Tnormal, the time counter of the ONU is gradually corrected based on the target time correction value.

[0117] Fig.10 FIG. 1 is a schematic diagram of the implementation principle of the time synchronization phase jump control provided by the present invention, such as Fig.10As shown, the embodiment of the present application improves the traditional PON time synchronization instruction execution mechanism, and modifies "obtaining the time correction value, and executing the correction instruction immediately when receiving the time correction trigger signal" to "obtaining the time correction value, not executing the correction instruction temporarily when receiving the time correction trigger signal, comparing the difference between the original correction value and the current value of the ONU's own time counter, storing the difference value in the ONU's own register, and actually executing the correction of the time counter according to the instruction timing and correction value issued by the ONU's own CPU".

[0118] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application facilitates the comparison of the primary and backup time correction values ​​of the single-fiber dual physical channels through the time synchronization phase jump control, controls the time synchronization error and avoids the degradation of the timing quality caused by the failure or degradation of a single channel. Moreover, it is also convenient to implement the time synchronization phase jump control before and after the switching of the time synchronization physical channel, and can achieve smoother amplitude control through multiple adjustments, thereby improving the timing quality of the terminal service equipment.

[0119] In some embodiments, the stepwise correction of the time counter of the ONU based on the target time correction value includes: Within a preset control time interval, the time counter of the ONU is corrected N times; the value of each correction is equal to 1 / N of the target time correction value.

[0120] Specifically, when the target time correction value is greater than or equal to the preset threshold, the timer is started. The working cycle of the timer is a preset control time interval Tcontroll. The ONU time counter is corrected N times at equal time intervals, N is a positive integer, and the value of each correction is equal to 1 / N of the target time correction value.

[0121] For example, three time counter corrections are performed at a time interval of Tcontroll / 3, each time △Tx / 3 is adjusted (△Tx is the target time correction value), the time counter correction is completed, the normal timing state is entered, and the physical channel state is monitored.

[0122] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application determines the target time correction value. If the adjustment range is large, the correction is completed three times within a certain time interval. This can smooth the jump of the time synchronization phase, so that when the primary and backup channels are switched, the phase jump of the timing signal obtained by the terminal service equipment is smaller and more stable.

[0123] The Combo FTTR-based PON system time synchronization method provided in the embodiment of the present application realizes time-synchronized dual physical channel active-standby protection switching when only a single optical fiber path is used without using Type B or Type C protection.

[0124] This single-fiber dual-physical channel active-standby synchronization method has three main advantages: First, the reliability of time synchronization is enhanced, avoiding synchronization loss or accuracy degradation caused by single physical channel failure. Typical single physical channel failures include partial optical transceiver failure or index degradation (in the Combo PON port, the optical transceiver devices of the GPON physical channel and the 10G PON physical channel are independent of each other), wavelength combination and wavelength division device index degradation (in the Combo PON port, the wavelength combination and wavelength division devices have no active-standby protection), and optical wavelength drift exceeding the limit.

[0125] Secondly, the master and backup synchronization passes through exactly the same optical fiber path, with no difference in the pigtail length, ONU internal processing time, chip processing flow, etc., so there is no need to adopt additional delay error measurement and compensation measures. This can minimize the measurement error between the master and backup channels, and correspondingly reduce the timing phase jump generated after channel switching, thereby reducing the impact on the terminal service equipment being clocked.

[0126] Third, at the start-up stage, the ONU will compare the time synchronization calculation results of the primary and backup physical channels. If the error exceeds the set range, the synchronization fault will be reported. This will enable timely detection of physical channel synchronization function failures (because under normal circumstances, the difference in calculation results between the primary and backup channels will not exceed a certain range), thus further reducing the synchronization error and avoiding operation with faults.

[0127] In addition, in the embodiment of the present application, only the working logic of the Combo FTTR ONU is modified without modifying its hardware requirements, so that the single-fiber dual-physical channel master-slave time synchronization mechanism can be realized, which greatly improves the reliability of terminal service timing under the premise of unchanged cost, and has good commercial prospects, especially for commercial users, industrial users and other application scenarios with high reliability timing requirements. Moreover, only the time synchronization correction instruction execution mechanism of the ONU is modified without modifying its hardware requirements, which can achieve smooth time synchronization phase jump control, further improve the quality of terminal service timing under the premise of unchanged cost, and has good commercial prospects.

[0128] Fig.11 is a schematic diagram of the structure of a PON system time synchronization device based on Combo FTTR provided by the present invention, such as Fig.11As shown, the present invention provides a PON system time synchronization device based on Combo FTTR, including a first determination module 1101, a second determination module 1102 and a synchronization module 1103.

[0129] The first determination module 1101 is used to receive first time synchronization information through a first physical channel and to receive second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT and a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT and the PON MAC of the ONU.

[0130] The second determination module 1102 is used to determine a target time correction value based on the detected time synchronization working status of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information.

[0131] The synchronization module 1103 is used to perform clock synchronization between the ONU and the OLT based on the target time correction value.

[0132] In some embodiments, the second determining module includes: A first determining submodule is configured to determine, when detecting that the time synchronization working state of the first physical channel is normal, that the target time correction value is the first time correction value; and / or The second determining submodule is used to determine a target time correction value according to the detected time synchronization working state of the second physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal.

[0133] In some embodiments, the second determining submodule includes: The first determining unit is configured to determine that the target time correction value is the second time correction value when it is detected that the time synchronization working state of the second physical channel is normal.

[0134] In some embodiments, it also includes: The synchronization tracking module is used to perform time synchronization tracking through the second physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal and the time synchronization working state of the second physical channel is normal.

[0135] In some embodiments, it also includes: The first fault reporting module is used to report a fault when it is detected that the time synchronization working state of the first physical channel and the time synchronization working state of the second physical channel are both abnormal.

[0136] In some embodiments, it also includes: The detection module is used to continuously detect the time synchronization working state of the first physical channel when it is detected that the time synchronization working state of the first physical channel is abnormal, and determine the target time correction value according to the detected time synchronization working state of the first physical channel.

[0137] In some embodiments, it also includes: A second fault reporting module is used to report a fault when the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal; and / or A judgment module is used to judge whether there is a time synchronization function abnormality in the first physical channel and / or the second physical channel based on the first time correction value and the second time correction value when the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal.

[0138] In some embodiments, the determination module includes: A judging submodule, used for judging whether the difference between the first time correction value and the second time correction value is within a preset range; A third determining submodule is configured to determine that there is no time synchronization function abnormality in the first physical channel and / or the second physical channel when the difference between the first time correction value and the second time correction value is within a preset range; and / or The fourth determining submodule is used to determine that a time synchronization function abnormality exists in the first physical channel and / or the second physical channel when the difference between the first time correction value and the second time correction value is not within a preset range.

[0139] In some embodiments, the following also include: a synchronization unit, configured to perform clock synchronization between the ONU and the OLT according to the first time correction value when the difference between the first time correction value and the second time correction value is within a preset range, and perform time synchronization tracking through the first physical channel; and / or; The fault reporting unit is used to report a fault when the difference between the first time correction value and the second time correction value is not within a preset range.

[0140] In some embodiments, the synchronization module includes: A first correction submodule, configured to correct the time counter of the ONU using the target time correction value when the target time correction value is less than a preset threshold; The second correction submodule is used to gradually correct the time counter of the ONU based on the target time correction value when the target time correction value is greater than or equal to a preset threshold.

[0141] In some embodiments, the second correction submodule includes: The time correction unit is used to correct the time counter of the ONU N times within a preset control time interval; the value of each correction is equal to 1 / N of the target time correction value.

[0142] In some embodiments, the first physical channel and the second physical channel use the same optical fiber path, and the optical transceiver device of the first physical channel and the optical transceiver device of the second physical channel are independent of each other.

[0143] Specifically, the above-mentioned Combo FTTR-based PON system time synchronization device provided by the present invention can implement all the method steps implemented by the above-mentioned Combo FTTR-based PON system time synchronization method embodiment, and can achieve the same technical effect. The parts and beneficial effects that are the same as those in the method embodiment will not be specifically repeated here.

[0144] It should be noted that the division of units / modules in the above-mentioned embodiments of the present invention is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, the functional units in the various embodiments of the present application may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware or in the form of software functional units.

[0145] Fig.12 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Fig.12 As shown, the electronic device may include: a processor 1201, a communications interface 1202, a memory 1203 and a communication bus 1204, wherein the processor 1201, the communications interface 1202, and the memory 1203 communicate with each other through the communication bus 1204. The processor 1201 may call the logic instructions in the memory 1203 to execute a PON system time synchronization method based on Combo FTTR, the method comprising: Receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT with a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT with the PON MAC of the ONU; Determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The clocks of the ONU and the OLT are synchronized based on the target time correction value.

[0146] Specifically, the processor 1201 can be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or a complex programmable logic device (CPLD), and the processor can also adopt a multi-core architecture.

[0147] The logic instructions in the memory 1203 can be implemented in the form of software functional units and can be stored in a processor-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0148] In some embodiments, a computer program product is further provided, the computer program product comprising a computer program, the computer program may be stored on a non-transitory computer-readable storage medium, and when the computer program is executed by a processor, the computer can execute the PON system time synchronization method based on Combo FTTR provided in the above-mentioned method embodiments, the method comprising: The first time correction value is determined by the time synchronization information received through the first physical channel, and the second time correction value is determined by the time synchronization information received through the second physical channel; the first physical channel is used to connect the first interface of the optical line terminal OLT and the passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect the second interface of the OLT and the PON MAC of the ONU; Determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The clocks of the ONU and the OLT are synchronized based on the target time correction value.

[0149] Specifically, the above-mentioned computer program product provided in the embodiment of the present application can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the method embodiment will not be described in detail here.

[0150] In some embodiments, a computer-readable storage medium is further provided, wherein the computer-readable storage medium stores a computer program, wherein the computer program is used to enable a computer to execute the ComboFTTR-based PON system time synchronization method provided in the above-mentioned method embodiments, the method comprising: Receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT with a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT with the PON MAC of the ONU; Determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The clocks of the ONU and the OLT are synchronized based on the target time correction value.

[0151] Specifically, the above-mentioned computer-readable storage medium provided by the present invention can implement all the method steps implemented by the above-mentioned method embodiments, and can achieve the same technical effects. The parts and beneficial effects that are the same as the method embodiments in this embodiment will not be described in detail here.

[0152] It should be noted that the computer-readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO), etc.), optical storage (such as CD, DVD, BD, HVD, etc.), and semiconductor storage (such as ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid-state drive (SSD)), etc.

[0153] It should also be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present invention can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first" and "second" are usually of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0154] In the present invention, the term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0155] In the present invention, the term "plurality" refers to two or more than two, and other quantifiers are similar to them.

[0156] In the present invention, "determine B based on A" means that the factor A should be considered when determining B. It is not limited to "B can be determined based on A alone", but should also include: "determine B based on A and C", "determine B based on A, C and E", "determine C based on A, and further determine B based on C", etc. In addition, it can also include taking A as a condition for determining B, for example, "when A meets the first condition, use the first method to determine B"; for another example, "when A meets the second condition, determine B", etc.; for another example, "when A meets the third condition, determine B based on the first parameter", etc. Of course, it can also be a condition that takes A as a factor for determining B, for example, "when A meets the first condition, use the first method to determine C, and further determine B based on C", etc.

[0157] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program codes.

[0158] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer executable instructions. These computer executable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0159] These processor executable instructions may also be stored in a processor readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the processor readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0160] These processor-executable instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0161] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A PON system time synchronization method based on Combo FTTR, characterized in that: Applicable to optical network unit (ONU), including: Receiving first time synchronization information through a first physical channel, and receiving second time synchronization information through a second physical channel; the first physical channel is used to connect a first interface of an optical line terminal OLT and a passive optical network media access control PON MAC of the ONU; the second physical channel is used to connect a second interface of the OLT and the PON MAC of the ONU; Determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The clocks of the ONU and the OLT are synchronized based on the target time correction value.

2. The Combo FTTR-based PON system time synchronization method according to claim 1, characterized in that: The step of determining a target time correction value according to the detected time synchronization working state of the first physical channel includes: When it is detected that the time synchronization working state of the first physical channel is normal, determining the target time correction value to be the first time correction value; and / or In the case where it is detected that the time synchronization working state of the first physical channel is abnormal, a target time correction value is determined according to the detected time synchronization working state of the second physical channel.

3. The Combo FTTR-based PON system time synchronization method according to claim 2, characterized in that: The step of determining the target time correction value according to the detected time synchronization working state of the second physical channel includes: When it is detected that the time synchronization working state of the second physical channel is normal, the target time correction value is determined to be the second time correction value.

4. The Combo FTTR-based PON system time synchronization method according to claim 3, characterized in that: The method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal and when it is detected that the time synchronization working state of the second physical channel is normal, time synchronization tracking is performed through the second physical channel.

5. The Combo FTTR-based PON system time synchronization method according to claim 1, characterized in that: The method further comprises: When it is detected that the time synchronization working state of the first physical channel and the time synchronization working state of the second physical channel are both abnormal, a fault report is performed.

6. The PON system time synchronization method based on Combo FTTR according to claim 1, characterized in that: The method further comprises: When it is detected that the time synchronization working state of the first physical channel is abnormal, the time synchronization working state of the first physical channel is continuously detected, and a target time correction value is determined according to the detected time synchronization working state of the first physical channel.

7. The Combo FTTR-based PON system time synchronization method according to claim 1 or 2, characterized in that: When the first power-on startup is completed, the method further includes: When the time synchronization working state of the first physical channel or the time synchronization working state of the second physical channel is abnormal, reporting a fault; and / or When the time synchronization working status of the first physical channel and the time synchronization working status of the second physical channel are both normal, it is determined whether there is a time synchronization function abnormality in the first physical channel and / or the second physical channel based on the first time correction value and the second time correction value.

8. The Combo FTTR-based PON system time synchronization method according to claim 7, characterized in that: The determining whether the first physical channel and / or the second physical channel has a time synchronization function abnormality based on the first time correction value and the second time correction value includes: Determining whether a difference between the first time correction value and the second time correction value is within a preset range; When the difference between the first time correction value and the second time correction value is within a preset range, determining that there is no time synchronization function abnormality in the first physical channel and / or the second physical channel; and / or When the difference between the first time correction value and the second time correction value is not within a preset range, it is determined that a time synchronization function abnormality exists in the first physical channel and / or the second physical channel.

9. The Combo FTTR-based PON system time synchronization method according to claim 8, characterized in that: The method further comprises: When the difference between the first time correction value and the second time correction value is within a preset range, performing clock synchronization between the ONU and the OLT according to the first time correction value, and performing time synchronization tracking through the first physical channel; and / or; When the difference between the first time correction value and the second time correction value is not within a preset range, a fault report is performed.

10. The PON system time synchronization method based on Combo FTTR according to claim 1, characterized in that: The performing clock synchronization between the ONU and the OLT based on the target time correction value includes: When the target time correction value is less than a preset threshold, the time counter of the ONU is corrected using the target time correction value; When the target time correction value is greater than or equal to a preset threshold, the time counter of the ONU is gradually corrected based on the target time correction value.

11. The Combo FTTR-based PON system time synchronization method according to claim 10, characterized in that: The stepwise correction of the time counter of the ONU based on the target time correction value comprises: Within a preset control time interval, the time counter of the ONU is corrected N times; the value of each correction is equal to 1 / N of the target time correction value.

12. The Combo FTTR-based PON system time synchronization method according to claim 1, characterized in that: The first physical channel and the second physical channel use the same optical fiber path, and the optical transceiver device of the first physical channel and the optical transceiver device of the second physical channel are independent of each other.

13. A PON system time synchronization device based on Combo FTTR, characterized in that: include: A first determining module, configured to receive first time synchronization information through a first physical channel, and receive second time synchronization information through a second physical channel; The first physical channel is used to connect the first interface of the optical line terminal OLT and the passive optical network media access control PON MAC of the ONU; The second physical channel is used to connect the second interface of the OLT and the PON MAC of the ONU; A second determination module is used to determine a target time correction value according to the detected time synchronization working state of the first physical channel; the target time correction value is a first time correction value or a second time correction value, the first time correction value is calculated based on the first time synchronization information, and the second time correction value is calculated based on the second time synchronization information; The synchronization module is used to synchronize the clocks of the ONU and the OLT based on the target time correction value.

14. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the PON system time synchronization method based on Combo FTTR according to any one of claims 1 to 12 is implemented.

15. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the PON system time synchronization method based on Combo FTTR as claimed in any one of claims 1 to 12 is implemented.

16. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the PON system time synchronization method based on Combo FTTR as claimed in any one of claims 1 to 12 is implemented.

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