A registration method and device of an optical communication network

Abstract

The application discloses a registration method and device of an optical communication network, and relates to the technical field of optical communication. A discovery window opened by an OLT is determined according to the distance between an optical relay device and a next-level optical network device of the optical relay device, and the OLT has configured specified BWmap information for the optical relay device, so that the OLT does not need to open a larger discovery window during the registration process of the next-level optical network device of the optical relay device, and only needs to open a discovery window suitable for the next-level optical network device. Therefore, the OLT only needs to open a smaller discovery window during the discovery process of an SN serial number, the time slot corresponding to the smaller discovery window is reduced, the service interruption time of other optical network devices in communication with the OLT is shortened, the uplink delay jitter of the optical communication network is reduced, and the communication stability of the optical communication network is improved.

Description

[0001] This application claims priority to the Chinese patent application No. 202311327280.2, filed on October 13, 2023, with the State Intellectual Property Office, and entitled "A registration method and device of an optical communication network", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the field of optical communication technology, in particular to a registration method and device of an optical communication network. BACKGROUND

[0003] Passive optical network (PON) is an access network based on optical fiber link transmission. In the PON, there is no electronic device using power between the optical line terminal (OLT) and the optical network unit (ONU). In the PON, the downlink transmission from the OLT to the ONU is in a broadcast mode, and the uplink transmission from the ONU to the OLT is in a time division multiple access (TDMA) mode. Therefore, in the uplink transmission process from the ONU to the OLT, the time slots occupied by different ONUs cannot overlap, and the information transmitted in the overlapping time slots cannot be correctly received by the OLT. Therefore, the ranging in the registration phase of the ONU is needed to determine the time slot allocated to the ONU in the normal service authorization.

[0004] In the registration process of the ONU, the OLT issues an authorization instruction and periodically opens a serial number (SN) discovery mute window (referred to as a discovery window) for the ONU. In the time slot corresponding to the discovery window, the ONU sends a SN signal to the OLT. Then, the OLT allocates a registration identifier to the ONU to be online according to the received SN signal and opens a ranging mute window (referred to as a ranging window). After that, the OLT performs ranging and authorization on the ONU to be online in the time slot corresponding to the ranging window, to complete the registration process of the ONU. Since the services of other ONUs connected to the OLT need to be interrupted in the time slots corresponding to the discovery window and the ranging window, in the case that the OLT connects a larger number of ONUs through multiple optical repeaters and the number of these ONUs is large (such as a PON remote network), the OLT needs to open the discovery window for a long time, which will bring large delay jitter. This brings challenges to the PON system in application scenarios with high delay jitter requirements. In order to reduce the uplink delay jitter caused by the registration process, a more effective registration method of an optical communication network is needed. SUMMARY

[0005] The application provides a registration method and device of an optical communication network, which solves the uplink delay jitter caused by the registration process and is beneficial to improving the communication efficiency of the optical communication network.

[0006] In a first aspect, the application provides a registration method of an optical communication network. The registration method is performed by a first network device in the optical communication network, the first network device has an optical communication connection with an optical relay device, the optical relay device has a specified bandwidth map (BWmap) information and a pre-allocated equalization delay in the optical communication network, and the specified BWmap information is different from standard BWmap information of the optical communication network. The registration method comprises the following steps: the first network device sends a first overhead message and a first discovery message to the optical relay device and opens a discovery window for the optical relay device; the first overhead message indicates optical parameters to be used by a next optical network device of the optical relay device for transmitting an optical signal, the first discovery message carries the specified BWmap information, and the size of the discovery window is determined according to the distance between the next optical network device of the optical relay device and the optical relay device. In a time slot corresponding to the discovery window, the first network device receives a first serial number (SN) sent by the optical relay device, and the first SN is a SN sent by the next optical network device of the optical relay device based on the optical parameters. Then, the first network device sends a ranging request message to the optical relay device according to the first SN and sends a registration identifier of the next optical network device of the optical relay device. Finally, the first network device receives a ranging message sent by the optical relay device and sends a response message to the optical relay device; the ranging message carries the registration identifier, and the response message is used to indicate an equalization delay to be used by the next optical network device of the optical relay device in the optical communication network.

[0007] In the application, the discovery window opened by the first network device is determined according to the distance between the optical relay device and the next optical network device of the optical relay device, and the first network device has configured the specified BWmap information for the optical relay device, so that the first network device does not need to open a large discovery window when performing the registration process of the next optical network device of the optical relay device, and only needs to open a discovery window suitable for the next optical network device. Therefore, the first network device only needs to open a small discovery window in the SN discovery process, the time slot corresponding to the small discovery window is reduced, the service interruption time of other optical network devices in communication with the first network device is shortened, and the uplink delay jitter of the optical communication network is reduced, the communication efficiency and the communication stability of the optical communication network are improved.

[0008] In an optional implementation, before the first network device sends the first overhead message to the optical relay device, the registration method provided in the application further includes: the first network device sends configuration information to the optical relay device that has been online in the optical communication network, and the configuration information is used to indicate the specified BWmap information and the pre-allocated equalization delay that can be used by the optical relay device in the optical communication network. Then, the first network device receives a response message sent by the optical relay device, and the response message indicates that the optical relay device has set the configuration information to the optical relay device.

[0009] In the application, the first network device can issue the configuration information, so that the optical network device to be registered and the configuration information adapted by the optical network device indicate the specified BWmap information and the pre-allocated equalization delay to communicate with the first network device, which avoids the problem that the first network device cannot correctly identify the devices due to the use of the same BWmap information and the pre-allocated equalization delay by different optical network devices, and is beneficial to improve the accuracy of the registration process of the optical communication network.

[0010] In an optional implementation, the first network device receives the ranging message sent by the optical relay device, and sends a response message to the optical relay device, including: the first network device receives the ranging message sent by the optical relay device, and parses the ranging message to obtain a registration identifier; and the first network device sends a response message to the optical relay device according to the registration identifier. In this way, the first network device determines that the optical network device to be online is a legal device according to the allocated registration identifier, and allocates a reasonable equalization delay to the optical network device to be online, so that the optical network device can access the optical communication network according to the equalization delay carried in the response message, avoids the communication abnormality caused by the access of illegal optical network devices to the optical communication network, such as the occupation of a large bandwidth to cause the low communication efficiency between multiple optical network devices, and improves the security of the optical communication network.

[0011] In an optional implementation, before the first network device sends the first discovery message to the optical relay device, the method provided in the application further includes: the first network device sends a standard discovery message to the optical relay device, and the standard discovery message carries standard SN window opening authorization information, which is used to indicate the discovery window opened by the first network device for any optical network device based on the standard BWmap information.

[0012] In the case where the first network device not only directly connects the optical relay device, but also directly connects other optical network devices, if the other optical network devices do not need to communicate with the first network device through the optical relay device, these other optical network devices can send the SN of the other optical network device to the first network device through the standard discovery message sent by the first network device, so that the first network device allocates a registration identifier to the other optical network device according to the SN, and performs the registration process of the other optical network device.

[0013] In a second aspect, the application provides a registration method of an optical communication network. The registration method is performed by an optical relay device, the optical relay device has an optical communication connection with a first network device in the optical communication network, and the optical relay device can use specified BWmap information and a second pre-allocated equalization delay in the optical communication network, the specified BWmap information is different from standard BWmap information of the optical communication network. The registration method comprises: the optical relay device receives a first discovery message sent by the first network device, and sends a second discovery message to a second network device according to the first discovery message; the first discovery message carries the specified BWmap information, and the second discovery message carries first standard SN windowing authorization information obtained according to the specified BWmap information, the first standard SN windowing authorization information indicates a discovery window opened by the first network device for the second network device according to the specified BWmap information, the size of the discovery window is determined according to the distance between the next optical network device of the optical relay device and the optical relay device, and the second network device is any one of the next optical network devices of the optical relay device. Then, the optical relay device receives a first SN sent by the second network device and sends the first SN to the first network device; the optical relay device receives a ranging request message and a registration identifier sent by the first network device, and sends the ranging request message and the registration identifier to the second network device; the registration identifier is a registration identifier allocated by the first network device for the second network device according to the first SN. And the optical relay device receives a ranging message sent by the second network device and sends the ranging message to the first network device, the ranging message carries the aforementioned registration identifier. Finally, the optical relay device receives a response message sent by the first network device and sends the response message to the second network device, the response message is used to indicate the equalization delay to be used by the second network device in the optical communication network.

[0014] In the application, the discovery window opened by the first network device is determined according to the distance between the optical relay device and the next optical network device of the optical relay device, and the first network device has configured the specified BWmap information for the optical relay device, so that in the registration process of the next optical network device of the optical relay device performed by the first network device, the first network device does not need to open a large discovery window, but only needs to open a discovery window suitable for the aforementioned next optical network device. Therefore, the optical relay device can set standard SN windowing authorization information for the next optical network device (the second network device) based on the aforementioned specified BWmap information, the discovery window indicated by the standard SN windowing authorization information is determined according to the distance between the next optical network device of the optical relay device and the optical relay device, therefore, the time slot corresponding to the discovery window is reduced, the business interruption time of other optical network devices in communication with the first network device is shortened, which is beneficial to reduce the uplink delay jitter of the optical communication network and improve the communication stability of the optical communication network.

[0015] In an optional implementation, before the optical relay device receives the first discovery message sent by the first network device, the registration method provided in the application further includes: the optical relay device receives a first overhead message sent by the first network device, and sends a second overhead message to a second network device according to the first overhead message. The first overhead message indicates an optical parameter to be used by a next-stage optical network device of the optical relay device for transmitting an optical signal, and the first overhead message carries a first pre-allocated equalization delay of the optical communication network. The second overhead message carries the second pre-allocated equalization delay mentioned above, and the second network device is any one of the next-stage optical network devices of the optical relay device. It should be understood that the optical relay device modifies the BWmap information in the overhead message to specified BWmap information, so that the next-stage optical network device can respond to the SN within the set time slot, thereby avoiding the problem of registration error or registration failure caused by the long-time non-response of the next-stage optical network device.

[0016] In an optional implementation, the optical relay device sends the second overhead message to the second network device according to the first overhead message, including: the optical relay device modifies the first pre-allocated equalization delay in the first overhead information to the second pre-allocated equalization delay set in the optical relay device, to obtain the second overhead message. And the optical relay device sends the second overhead message to the second network device.

[0017] In an optional implementation, the optical relay device sends the second discovery message to the second network device according to the first discovery message, including: the optical relay device converts the specified BWmap information in the first discovery message to first standard SN windowing authorization information, to obtain the second discovery message. And the optical relay device sends the second discovery message to the second network device.

[0018] In an optional implementation, before the optical relay device receives the first discovery message sent by the first network device, the registration method provided in the application further includes: the optical relay device receives a standard discovery message sent by the first network device, and the standard discovery message carries the first standard SN windowing authorization information mentioned above. Then, the optical relay device deletes the first standard SN windowing authorization information in the standard discovery message, to obtain an invalid message, and sends the invalid message; or, the optical relay device terminates the transmission process of the standard discovery message in the optical communication network. In the application, the optical relay device can end the transmission of other optical signals after the SN, thereby avoiding the problem of decreased registration efficiency and increased uplink delay jitter caused by the fact that the first network device receives more optical signals.

[0019] In an optional implementation, the optical relay device receives the first SN sent by the second network device, and sends the first SN to the first network device, including: the optical relay device receives the first SN sent by the second network device, and after receiving the first SN, the optical relay device sets the optical signal of the second network device received in the discovery window as an invalid optical signal.

[0020] In a third aspect, the present application provides a registration apparatus. The registration apparatus comprises a software unit or module for executing any optional implementation of the first aspect or the second aspect.

[0021] In a fourth aspect, the present application provides an optical network device. The optical network device comprises a processor, a memory and a transceiver. The memory is configured to cache: a specified BWmap information and a pre-allocated equalization delay that can be used by an optical relay device having an optical communication connection with the network device in an optical communication network, the specified BWmap information being different from a standard BWmap information of the optical communication network. The transceiver and the processor are configured to perform the method of any optional implementation of the first aspect.

[0022] In a fifth aspect, the present application provides an optical relay device. The optical relay device comprises a processor and a transceiver. The processor and the transceiver are configured to perform the method of any optional implementation of the second aspect.

[0023] In a sixth aspect, the present application provides a communication system. The communication system comprises: an optical fiber, one network device provided in the fourth aspect, and one or more optical relay devices provided in the fifth aspect, the optical fiber being configured to connect the devices.

[0024] The beneficial effects of any one of the third aspect to the sixth aspect can be referred to the description of any optional implementation of the first aspect to the third aspect, which will not be repeated here. The implementation of the above aspects provided by the present application can be further combined to provide more implementation. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A structure schematic diagram of an optical communication network provided by the present application is shown in the figure;

[0026] Figure 2 A structure schematic diagram of a PON remote network provided by the present application is shown in the figure;

[0027] Figure 3 A structure schematic diagram of an OLT, an optical relay device and an ONU provided by the present application is shown in the figure;

[0028] Figure 4 A flow schematic diagram of a registration method of an optical communication network provided by the present application is shown in the figure;

[0029] Figure 5A comparison diagram of different registration methods provided in the present application is shown in FIG. 1.

[0030] Figure 6 A structural diagram of a registration device provided in the present application is shown in FIG. 2.

[0031] Figure 7 A structural diagram of an optical network device provided in the present application is shown in FIG. 3. DETAILED DESCRIPTION

[0032] For the sake of clear and concise description of the following embodiments, a brief introduction of related technologies is given first.

[0033] Discovery window: In the process of registering to an optical communication network, an OLT opens a quiet window for discovering SNs of ONUs to be online. In the time slot corresponding to the discovery window, the services of other ONUs that have registered to the optical communication network are interrupted. The time slot corresponding to the discovery window refers to the time period during which the discovery window exists after the OLT opens the discovery window. In some examples, the discovery window is also referred to as an SN discovery window. In the scenario of a PON remote network, the discovery window refers to a quiet window opened by an OLT for discovering SNs of multiple ONUs to be online connected through one or more optical relay devices.

[0034] Ranging window: In the process of registering to an optical communication network, an OLT opens a quiet window for ranging of ONUs to be online. In the time slot corresponding to the ranging window, the services of other ONUs that have registered to the optical communication network are interrupted. The time slot corresponding to the ranging window refers to the time period during which the ranging window exists after the OLT opens the ranging window. In the scenario of FTTR, the ranging window refers to a quiet window opened by a master ONU for ranging of a slave ONU to be online. In the scenario of a PON remote network, the ranging window refers to a quiet window opened by an OLT for ranging of multiple ONUs to be online connected through one or more optical relay devices.

[0035] Figure 1 A structural diagram of an optical communication network provided in the present application is shown in FIG. 4. The optical communication network can also be referred to as an optical transmission network. The optical communication network includes multiple optical network devices, one or more of which are used to connect terminals of users (such as terminals 111-115 shown in FIG. 1). Figure 1

[0036] A terminal can also be referred to as a terminal device, a user equipment (UE), a mobile station (MS), a mobile terminal (MT), etc.

[0037] In some embodiments, a terminal can be a mobile phone (such as the terminal 111 shown in FIG. 1), a tablet computer (such as the terminal 112 shown in FIG. 1), a wearable device (such as the terminal 113 shown in FIG. 1), a vehicle-mounted device (such as the terminal 114 shown in FIG. 1), or a smart home device (such as the terminal 115 shown in FIG. 1). Figure 1 In some embodiments, a terminal can be a mobile phone (such as the terminal 111 shown in FIG. 1), a tablet computer (such as the terminal 112 shown in FIG. 1), a wearable device (such as the terminal 113 shown in FIG. 1), a vehicle-mounted device (such as the terminal 114 shown in FIG. 1), or a smart home device (such as the terminal 115 shown in FIG. 1).​Figure 1 terminal 112 shown in FIG. 1, a computer with wireless transceiver function (e.g., terminal 113 shown in FIG. 1), a personal communication service (PCS) phone (e.g., terminal 114 shown in FIG. 1), a desktop computer (e.g., terminal 115 shown in FIG. 1), a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in a smart home, and the like. Figure 1 Figure 1 Figure 1

[0038] In this embodiment, the optical network device can be a routing and forwarding device with optical communication function, a home gateway, or a network device in other forms, and the like. For example, the routing and forwarding device can be a router or a switch supporting fiber connection, and the like. The network device can also be a broadband network gateway (BNG) or a Broadband Remote Access Server (BRAS) with optical communication function, and the like. The home gateway can be an optical network terminal (ONT), for example. For example, the optical network device 121, the optical network device 124, and the optical network device 125 shown in FIG. 1 can be optical network terminals. The optical network terminal can access the Internet for user devices such as PCs, mobile phones, and the like. The home gateway can transmit data of the following services: online services (such as interactive network television services including video on demand, live services, and remote education, and the like) supported by the home gateway, online game services (e.g., game terminals carrying out game services through the home gateway), Internet Protocol (IP) phones, video phones, and video monitoring services, and the like. For another example, the home gateway can also implement home control and security service management on a remote network. For example, a user with a home gateway can access the automatic lighting, heating, and security systems, and the like in the area covered by the home gateway during work or travel. Embodiments of the present application do not limit the specific technology and specific device form adopted by the terminal. Figure 1

[0039] For example, the optical network devices are connected by optical cables. For example, the optical cable between the optical trunk device 122 and the optical trunk device 123 can be referred to as an access backbone layer optical cable, and the optical cable between the optical trunk device 123 and the optical network device 127 can include a distribution layer optical cable and a drop layer optical cable. The distribution layer optical cable refers to the optical cable between the optical trunk device 123 and the optical splitter 126, and the drop layer optical cable refers to the optical cable between the optical splitter 126 and the optical network device 127. Figure 1 ​​​​The optical cable between the optical splitter and the optical network device 127 is referred to as the drop cable.

[0040] The terminal can access the server by using the network device. As shown in Figure 1 , the user can use the terminal 111 to establish a wireless communication connection with the optical network device 127 by using wireless-fidelity (WIFI) technology, so that the terminal 111 sends a data packet to the server 130. For example, the optical network devices communicate with each other through optical fibers, and the optical network device 127 communicates with the terminals through WIFI. As an optional implementation, the optical network device 127 and the terminals can communicate with each other through a WIFI channel such as .

[0041] In some possible cases, the terminal can also use optical communication technology to establish a communication connection with a radio access network (RAN) device (not shown in Figure 1 ) and access the server 130.

[0042] The server 130 can be an application server or an authentication and authorization server. The server 130 can provide video services, game services, message services, music services, authentication and authorization services, and the like. The server 130 can also provide interactive TV (IPTV), voice over Internet Protocol (VoIP), or other services, and the like. In an example, the functions of multiple services can be integrated on the server 130, for example, game services and music services can be deployed on the server 130. In another example, the server 130 can also integrate the functions of part of the services, for example, the server 130 deploys part of the game services and part of the video services. The server 130 can also use virtualization technology to provide multiple virtual machines, and the virtual machines provide the services. The embodiments of the present application do not limit the deployment form of the services.

[0043] The optical network device is connected to the server 130 by wireless or wired means. Figure 1 This is only a schematic diagram, and the optical communication network can also include other devices, which are not shown in Figure 1 . The embodiments of the present application do not limit the number of terminals, optical network devices, and servers included in the optical communication network.

[0044] The present application can be applied to PON, passive optical LAN (POL), industrial optical network, or PON remote network, etc. For example, in a PON scenario, the optical transmitting device can be located in a user's home or user's corridor, and the optical receiving device can be located in an operator's machine room. In a POL scenario, the optical transmitting device and the optical receiving device can be located in a park (such as an enterprise, a campus, etc.). In an industrial optical network scenario, the optical transmitting device and the optical receiving device can be located in an industrial manufacturing workshop. In a vehicle-mounted optical network scenario, the optical transmitting device and the optical receiving device can be arranged in a vehicle. For example, in a PON scenario, each optical network device can be an optical network unit (ONU) or an ONT, and the network device 121 can be an OLT. As another example, in a PON scenario, the network device 121 can be a master ONU, and the optical network device 124 can be a slave ONU. In a vehicle-mounted optical network scenario, the optical transmitting device can be a vehicle interface unit (VIU), and the optical receiving device can be a mobile data center (MDC), a vehicle dynamic control (VDC), or a cockpit data center (CDC). The technical solutions provided in the present application can also be applied to optical backbone transmission networks, data center optical transmission, short-distance optical interconnection, and wireless service front-haul / backhaul, etc. Specifically, the technical solutions provided in the present application can be used for optical transmitting devices and / or optical receiving devices corresponding to different networks. For example, in a PON scenario, the embodiments of the present application can be applied to a time division multiplexing passive optical network (TDM-PON), and can also be applied to a wavelength division multiplexing passive optical network (WDM-PON), and can also be applied to a time and wavelength division multiplexing passive optical network (TWDM-PON). For example, the PON can refer to a GPON (Gigabit-Capable PON), an XG-PON based on an upgraded version of the GPON, a 10G EPON, etc., and can also refer to an EPON, an XGS PON, a 50G PON, etc. The present application is not limited in this regard.

[0045] The present application provides a registration method of an optical communication network. The registration method comprises the following steps: receiving a registration request of a network device; determining whether the network device is a new network device; if the network device is a new network device, sending a registration request of the network device to a network management device; receiving a registration response of the network device from the network management device; and updating a network topology of the optical communication network according to the registration response of the network device. Figure 2This is a schematic diagram of the PON remote network provided in this application. Figure 2 As shown, multiple ONUs (such as ONU1 to ONU8) communicate with the OLT 210 through optical network equipment such as optical splitters, single-level or multi-level optical repeaters.

[0046] It should be understood that PON is a passive optical network. In a PON remote network, line loss during transmission determines the splitting ratio and transmission distance. PON remote networks deploy active single-stage or multi-stage optical repeaters within the PON network. These repeaters amplify the optical signal, thus solving the problem of limited splitting ratio and transmission distance in PON remote networks.

[0047] On the access side of the optical communication network (the network side near the OLT 210), the optical relay equipment 221 can be deployed in the central office equipment room. The optical relay equipment in the central office equipment room transmits and receives optical signals, such as transmitting the collected optical signals to the OLT 210 through optical cables (such as optical fibers) to transmit the data carried by the optical signals to the data communication layer of the optical communication network.

[0048] On the customer side of the optical communication network (the network side close to each ONU), the optical relay equipment 222 can be deployed in a remote equipment room. The optical relay equipment in the remote equipment room transmits and receives optical signals, such as transmitting the optical signals collected from each ONU to the next-level optical relay equipment (such as the optical relay equipment 221 in the central office equipment room) through optical cables (such as optical fibers).

[0049] For example, the signal frames sent by ONU1 to ONU8 to OLT 210 are optical signal t1 to optical signal t8 respectively. After receiving the optical signals sent by each ONU, OLT 210 executes the service or operation indicated by the optical signal, such as putting the ONU online, ranging, or data communication, etc.

[0050] As one possible implementation method, Figure 2 The hardware implementation of the OLT, optical repeater, and ONU shown can be adopted using Figure 3 The way it is provided Figure 3 This is a schematic diagram of the structure of the OLT, optical repeater equipment, and ONU provided in this application, wherein the ONU310 can be... Figure 2 As shown, any one of ONU1 to ONU8 can be used by OLT 320 to register ONU 310 to the optical communication network. For example, OLT 320 can be used to implement... Figure 2 The functions of the OLT 210 are shown.

[0051] like Figure 3As shown, the ONU 310 includes an ONU media access control (MAC) 311, an ONU physical layer (PHY) 312, a laser 313, and a photodetector 314.

[0052] In the transmitting direction, the ONU MAC 311 can control the turning on and off of the laser 313 through a transmit enable port (Tx_En, also referred to as a switch pin). For example, if the ONU 310 is currently in a light-emitting time slot (also referred to as an occupied time slot), the ONU MAC 311 controls the laser 313 to turn on through the transmit enable port, and if the ONU 310 is not in a light-emitting time slot, the ONU MAC 311 controls the laser 313 to turn off through the transmit enable port. The ONU MAC 311 can also adjust the physical parameters of the laser 313, such as the laser bias current and the modulation current, through a transmit control port (Tx_Ctr). The ONU MAC 311 can send service data to the ONU PHY 312 through a data port (Data), and the ONU PHY 312 transmits the service data. The ONU PHY 312, also referred to as the driver of the laser 313, drives the laser to generate an optical signal according to the instructions of the transmit enable port and / or the transmit control port of the ONU MAC 311. The laser 313 modulates the service data into an optical signal under the control of the ONU PHY 312, and sends the uplink optical signal carrying the service data to the OLT 320 through an optical fiber.

[0053] In the receiving direction, the photodetector 314 receives a downlink optical signal from the OLT 320 and converts the downlink optical signal into an electrical signal. The ONU PHY 312 transmits the electrical signal, and the ONU MAC 311 analyzes the electrical signal to obtain the service data. The ONU 310 can also include a wavelength division multiplexer 315 for sending the uplink optical signal generated by the laser 313 into an optical fiber, and sending the downlink optical signal received from the optical fiber to the photodetector 314.

[0054] In this embodiment, the ONU 310 can also include a WIFI PHY and an antenna, and the WIFI PHY is used to establish a WIFI channel (or WIFI link) between the ONU 310 and the OLT 320 through the antenna. The WIFI channel can include but is not limited to: a connection and an interconnection channel based on a distributed system implementation, such as Harmony OS Connect TM Harmony OS Connect TM is a connection between and Harmony OS TMThe manner of interconnection between the devices obtained after integration. It is worth noting that different manufacturers can record the WIFI channel as different names according to the different hardware devices in the device, the different names of the device, etc., so as to realize the coordination between the WIFI communication and the optical communication between the devices, and improve the efficiency and robustness of the optical communication. For example, when the ONU 310 includes a WIFI PHY and an antenna, the ONU 310 can refer to an optical network device 127 in Figure 1 , i.e., a router or switch supporting optical communication function.

[0055] The wireless communication function of the ONU 310 and the OLT 320 can be realized by an antenna and a mobile communication module, a modulation and demodulation processor, and a baseband processor (not shown in the figure) and the like. For example, the antenna is used to transmit and receive electromagnetic wave signals. Each antenna can be used to cover a single or multiple communication frequency bands. Different antennas can also be multiplexed to improve the utilization rate of the antenna. For example: the antenna can be multiplexed as a diversity antenna of a wireless local area network. In some embodiments, the antenna can be used in combination with a tuning switch. For the mobile communication module, taking the ONU 310 as an example, at least part of the functional modules of the mobile communication module can be arranged in the WIFI PHY included in the ONU 310, or at least part of the functional modules of the mobile communication module can be arranged in the same device as at least part of the modules of the WIFI PHY.

[0056] The OLT 320 can include an OLT MAC 321, an OLT PHY 323 (including a signal processing module), a photodetector 324, and a laser 325. In the receiving direction, the photodetector 324 receives the uplink optical signal from the ONU 310 and converts the uplink optical signal into an electrical signal. The electrical signal can be an analog electrical signal or a digital electrical signal. The signal processing module can be implemented by an analog device (such as an amplifier) or a digital device (such as a digital signal processor), so the signal processing module can perform analog-related processing or digital electrical signal processing. The OLT MAC 321 analyzes the electrical signal processed by the signal processing module to obtain service data. In the transmitting direction, the OLT MAC 321 generates service data, and the signal processing module performs analog or digital related processing on the service data. The laser 325 modulates the service data into an optical signal under the control of the OLT PHY 323, and sends the downlink optical signal carrying the service data to the ONU 310 through an optical fiber. The OLT 320 can also include a wavelength division multiplexer 326 for sending the downlink optical signal generated by the laser 325 to the optical fiber, and sending the uplink optical signal received from the optical fiber to the photodetector 324.

[0057] As Figure 3As shown, the optical relay device 330 can include a processor 332. Optionally, the optical relay device 330 can also include a memory 333 and / or a transceiver 331. The processor 332 is coupled to the memory 333 and the transceiver 331, e.g., through a communication bus.

[0058] The following description will be made in conjunction with Figure 3 The various components of the optical relay device 330 will be described in detail.

[0059] The processor 332 is the control center of the optical relay device 330, and can be one processor or a collective term of multiple processing elements. For example, the processor 332 can be one or more central processing units (CPUs), application specific integrated circuits (ASICs), or one or more integrated circuits configured to implement one or more embodiments of the present application, such as one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs).

[0060] Optionally, the processor 332 can perform various functions of the optical relay device 330 by running or executing software programs stored in the memory 333, and invoking data stored in the memory 333. In a specific implementation, as an embodiment, the processor 332 can include one or more CPUs. Optionally, the optical relay device 330 can also include multiple processors. Each of these processors can be a single-CPU or a multi-CPU. The processor herein can refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0061] The memory 333 is used to store the software program executing the solution of this application, and is controlled by the processor 332 for execution. Specific implementation methods can be found in the above-described method embodiments, and will not be repeated here. For example, the memory 333 can be a read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, random access memory (RAM) or other types of dynamic storage devices capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited to these. The memory 333 can be integrated with the processor 332, or it can exist independently, and is connected via the interface circuit of the optical relay device 330. Figure 3 (Not shown in the image) is coupled to processor 332, and this embodiment does not specifically limit this.

[0062] Transceiver 331 is used for communication with other communication devices. For example, transceiver 331 can be used to communicate with ONU 310, OLT 320, or other optical repeater equipment. Optionally, transceiver 331 may include a receiver and a transmitter. Figure 3 (Not shown separately). The receiver is used to receive optical signals, and the transmitter is used to transmit optical signals.

[0063] Optionally, the transceiver 331 can be integrated with the processor 332, or it can exist independently and be connected via the interface circuit of the optical repeater 330. Figure 3 (Not shown in the image) is coupled to processor 332, and this embodiment does not specifically limit this.

[0064] It is worth noting that, Figure 3 The structure of the optical repeater device 330 shown does not constitute a limitation on the communication device. Actual communication devices may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0065] Furthermore, the technical effects of the optical relay device 330 can be referred to the technical effects described in the following method embodiments, which will not be repeated here.

[0066] The ONU accesses the optical communication network in the OLT includes the following stages: discovery stage, ranging stage, authentication stage and running stage. The discovery stage refers to the OLT for ONU open SN discovery window, and according to the SN obtained for ONU allocation registration identifier, such as the identification (ID) of ONU. The ranging stage refers to the OLT for ONU open ranging window, and according to the ranging message of ONU for ONU allocation equalization delay. The authentication stage includes: ONU in the SN authentication of OLT, password authentication, etc. The running stage includes: optical network unit management and control interface (ONU management and control interface, OMCI) configuration recovery and OMCI management, traffic flow, etc. Such as ONCI management includes: the establishment of OLT and ONU between the traffic flow, traffic flow encryption, forward error correction (FEC) for traffic flow, etc.

[0067] Generally, ONU to access to the network, to be legitimate, ONU activation, the activation process is under the control of the OLT. The embodiment is described from the perspective of ONU activation process.

[0068] The activation process mainly includes three stages: downlink synchronization stage, sequence number acquisition (ONU discovery) stage and ranging stage.

[0069] In the downlink synchronization stage, the ONU power on will enter the initial state, initialize the local embodiment of the downstream synchronization state machine, realize the synchronization with the downlink signal, and begin to learn the system, channel and burst profile parameters. In the TWDM-PON system, the ONU can repeat the process for two or more available downlink wavelength channels, and can create and store the calibration records of these channels. After the ONU selects a downlink wavelength channel to continue the activation process, this stage ends.

[0070] Specifically, the initial state further comprises an Off-Sync sub-state and a Profile Learning sub-state; in the Off-Sync sub-state, the ONU searches for and attempts to synchronize to downstream signals, and once the ONU achieves downstream synchronization, the ONU transitions to the Profile Learning sub-state; it should be understood that if the downstream synchronization state machine of the ONU enters the synchronized state from the pre-synchronized state, it is considered that the ONU achieves downstream synchronization, and the ONU will perform state transition. Similarly, if the ONU loses downstream synchronization in the Profile Learning sub-state, i.e., the downstream synchronization state machine of the ONU returns to the search state from the pre-synchronized state, the ONU will return to the Off-Sync sub-state and continue to search for and attempt to synchronize to downstream signals. Ensuring that the ONU has achieved downstream synchronization before performing subsequent operations avoids a large number of decoding errors and ensures the normal progress of the ONU activation process and the normal work of the activated ONU.

[0071] After entering the Profile Learning sub-state, the ONU parses the physical layer operation, administration, and management (PLOAM) information of the downstream framing sublayer (FS) frame and starts collecting system, channel, and burst profile information. Once sufficient information is collected, the ONU performs upstream wavelength option evaluation in a TDM-PON system with multiple upstream wavelength options. In a TDM-PON system with multiple upstream wavelength options (e.g., a 50G TDM-PON), if the ONU supports at least one of the upstream wavelength options included in the operation control body (OC body) or Burst_Profile message, it continues to activate and transitions to the Serial Number state. Otherwise, the ONU stops activation.

[0072] In the serial number acquisition phase, the ONU enters the serial number state, and the ONU activates its transmitter to declare its presence in the PON network by responding to a serial number grant, i.e. once the ONU receives the serial number grant, the ONU sends serial number management maintenance information, wherein the serial number grant is used to indicate that the ONU to be activated is allowed to join the passive optical network or the offline ONU re-enters the passive optical network, and the serial number management maintenance information is used to indicate the serial number and random delay of the ONU; it should be understood that the serial number management maintenance information can be Serial_Number_ONU PLOAM message.

[0073] Further, the ONU will decide whether to remain in the current state or enter the ranging phase according to the indication information of the OLT. When the OLT allocates a unique ONU-ID to the ONU to be activated, i.e. when the OLT discovers the new ONU, the phase ends.

[0074] In the ranging phase, the ONU waits for the equalization delay allocated by the OLT and responds to the directional ranging grant. When the OLT completes the round-trip delay measurement, calculates the equalization delay and transmits the equalization delay to the ONU, the phase ends. The ONU adjusts its uplink clock according to the equalization delay allocated by the ONU, at this time, the ONU completes the activation and starts to work.

[0075] It should be noted that if there is a special activation wavelength in the passive optical network system, the above three phases can be carried out in the activation wavelength channel, and the activation wavelength is different from the uplink wavelength used in the working state.

[0076] It should be noted that the compatibility of 50G PON has always been the focus of global operators. In order to ensure that GPON or XGSPON devices can still be used, and to protect the investment of operator network construction, 50G PON defines three uplink wavelength options: 1260nm-1280nm, 1290nm-1310nm, 1284nm-1288nm; since the uplink wavelength of the GPON network is 1290nm-1330nm, and the uplink wavelength of the XGSPON network is 1260nm-1280nm, the operator can select different wavelength options according to the network and industry chain of the operator.

[0077] In the embodiment, the initial state of the ONU includes the Off-Sync sub-state and the Profile Learning sub-state, and the manner of state switching is described, which is relatively simple to implement. In addition, the activation process of the ONU in the 50G PON network needs to pay attention to whether the ONU supports at least one of multiple uplink wavelength options, and only when at least one uplink wavelength option is supported, the ONU can enter the next state and activate the transmitter of the ONU, so as to ensure that the ONU can communicate with the OLT in uplink according to the wavelength adapted by the 50G PON network, and the compatibility of the existing 50G PON network is not damaged.

[0078] In the prior art, in the scenario of PON remote network, in the case that the OLT connects a larger number of ONUs through multiple optical repeaters, and the number of the ONUs is large (such as PON remote network), the OLT needs to open the discovery window for a long time, which will bring large delay jitter. This brings challenges to the PON system in the application scenario with high delay jitter requirement.

[0079] In order to reduce the uplink delay jitter caused by the registration process, in the above Figures 1 to 3 , the optical communication network and the OLT, the optical relay device and the ONU are shown, and embodiments of the present application provide a possible implementation manner, as shown in Figure 4 , the registration method of the optical communication network provided by the present application is shown. Figure 4 The hardware implementation and optional implementation manner of the OLT 41, the optical relay device 42, the ONU 43 and the ONU 44 can refer to the description of the foregoing Figures 1 to 3 , and will not be described here. In some optional implementation manners, Figure 4 , the ONU to be online can also be referred to as the next level optical network device connected to the optical relay device 42.

[0080] Please refer to Figure 4 , the registration method provided by the embodiment includes the following S401 to S416.

[0081] S401. The OLT 41 establishes an optical communication connection with the optical relay device 42.

[0082] For the implementation process of S401, a possible specific example is provided below. In this example, the data frame refers to a signal frame transmitted in the form of optical signal.

[0083] Step 1: The OLT 41 continuously broadcasts data frames to multiple optical relay devices 42, and each data frame carries control information; the control information is used to indicate the optical relay device 42 to go online, ranging or registration in the optical communication network. In this embodiment, in combination with Figure 3For example, the data frame can be an optical signal generated by the OLT PHY 323 driving the laser 325 after the OLT MAC 321 generates data to be transmitted.

[0084] Optionally, the data frame can also be used to instruct the optical relay device 42 to forward one or more specific optical signals, or to interrupt the transmission of one or more specific optical signals in the optical relay device 42, etc.

[0085] The process of establishing the optical communication connection between the OLT 41 and the optical relay device 42 is described below by way of example.

[0086] Step 2: The optical relay device 42 performs frame synchronization on the received data frame, and establishes the optical communication connection with the OLT 41.

[0087] The frame synchronization refers to the optical relay device 42 performing frame synchronization on the received serial signal. The frame synchronization refers to the optical relay device 42 determining the start position and end position of a data frame in the serial signal by identifying the start and end of the frame. The frame synchronization method can include, but is not limited to, at least one of character counting, start and end delimiter with character padding, start and end flag with bit padding, and physical layer coding violation.

[0088] The process of frame synchronization is described below by way of example using the start and end flag with bit padding method. The frame header of each data frame carries a specific bit string (e.g., 0101). If the optical relay device 42 identifies the specific bit string, the optical relay device 42 determines that it has identified the frame header of a data frame, and considers the data in the serial data before the next frame header as the data of the data frame, thereby achieving frame synchronization of the data frame. In some possible cases, the frame synchronization is also referred to as "frame delimiting".

[0089] In some optional embodiments, since the frame length of each data frame is the same, after the optical relay device 42 finds the frame header of the data frame 1 (e.g., the specific bit at the start position of the frame header is 0101), the optical relay device 42 can delay for one frame length of the data frame to identify the frame header of the next data frame (e.g., the data frame 2).

[0090] The above example only provides a possible implementation of the start and end flag with bit padding method, and should not be construed as a limitation on the present application. The optical relay device 42 can also use other frame synchronization methods to achieve frame synchronization of the data frame. The specific implementation of the character counting, start and end delimiter with character padding, and physical layer coding violation methods can be referred to the description of the general technology, and will not be described here.

[0091] Step 3: The optical relay device 42 parses the data frame to obtain the control information, and starts the process corresponding to the control information.

[0092] In the embodiment, if the control information is used to indicate that the optical relay device 42 and its next level optical network device are online in the optical communication network of the OLT 41, the corresponding process of the control information is that the optical relay device 42 starts the ranging and registration process, and completes the ranging and is online in the optical communication network. Therefore, in some examples, the process of establishing the optical communication connection between the OLT and the optical relay device can also be referred to as the process of completing the ranging and being online of the optical relay device and the OLT. After the OLT 41 establishes the optical communication connection with the optical relay device 42, the following step S402 is continued.

[0093] S402. The OLT 41 sends configuration information to the optical relay device 42.

[0094] Corresponding to the process of S402, the optical relay device 42 receives the configuration information sent by the OLT 41.

[0095] The configuration information includes specified bandwidth map (BWmap) information and pre-allocation equalization delay (preEqd) that the optical relay device 42 can use in the optical communication network. The specified BWmap information indicates the position range of a single data frame in a plurality of continuously transmitted data frames (or can be referred to as a data block) and the position of the bandwidth allocation slot in the burst in the burst transmission mode. Each allocation slot is controlled by the bandwidth allocation structure specific to the BWmap in the downlink frame. The pre-allocation equalization delay (preEqd) is used to indicate the channel to be used by the next level optical network device in the service communication process between the OLT and the next level optical network device of the optical relay device.

[0096] In the embodiment, the specified BWmap information described above is different from the standard BWmap information in the optical communication network.

[0097] It is worth noting that, Figure 4 Only one optical relay device connected to the OLT 41 is shown in the figure, but in some optional implementations, the configuration information allocated by the OLT 41 for different optical relay devices is different, that is, the BWmap information and the equalization delay that can be used by the next level optical network device of different optical relay devices are different, thereby avoiding the problem of disorder of data transmission in the optical communication network caused by the use of the same equalization delay by different optical network devices, and facilitating to improve the communication robustness of the optical communication network.

[0098] For example, the process of determining the configuration information to be allocated for different optical relay devices by the OLT 41 can be random or can be performed according to a set logic or algorithm, which is not limited in the present application.

[0099] S403. The optical relay device 42 sends a response message 0 to the OLT 41.

[0100] Corresponding to the process of S403, the OLT 41 receives the response message 0 sent by the optical relay device 42.

[0101] The response message 0 is used to indicate that the optical relay device 42 has set the configuration information into the optical relay device 42. In some possible examples, the response message 0 is also called a configuration success response or a configuration response message, which is not limited in the present application.

[0102] S404. The OLT 41 sends an overhead message 1 to the optical relay device 42.

[0103] Corresponding to the process of S404, the optical relay device 42 receives the overhead message 1 sent by the OLT 41.

[0104] The overhead message 1 is also called a first overhead message, which carries a first pre-allocated equalization delay (first preEqd). The first preEqd is a preEqd set by the OLT 41 in the discovery stage of each optical network device to be online, which can be preset or user-set. In some cases, the first preEqd can also be called a standard preEqd of the OLT 41, which is not limited in the present application.

[0105] S405. The optical relay device 42 sends an overhead message 2 to the ONU to be online based on the overhead message 1.

[0106] It is worth noting that, for example, the ONU to be online refers to the ONU 43. Corresponding to the process of S405, the ONU 43 receives the overhead message 2 sent by the optical relay device 42. Figure 4

[0107] The overhead message 2 is also called a second overhead message, which carries a second pre-allocated equalization delay (second preEqd). The second preEqd is a pre-allocated equalization delay included in the configuration information in S402. In some possible cases, the second preEqd can also be called a special preEqd of the optical relay device 42.

[0108] For the optical relay device 42, the above S405 can include the following steps: the optical relay device 42 modifies the pre-allocated equalization delay (first preEqd) in the overhead message 1 to the pre-allocated equalization delay (second preEqd) carried by the configuration information to obtain the overhead message 2. For example, the pre-allocated equalization delay in the overhead message 1 is preEqd1, and the pre-allocated equalization delay in the overhead message 2 is preEqd2. ​

[0109] The overhead messages above are all used to indicate the optical parameters to be used by the next level optical network device of the optical relay device 42. The optical parameters here can include but are not limited to the frequency information to be used by the ONU to send optical signals to the optical relay device 42, or the signal transmission power to be used by the laser in the ONU (such as the laser 313 in the ONU 43) and the like. Figure 3

[0110] In this embodiment, the OLT can configure different pre-allocation equalization delays for different optical relay devices, and in the registration process of the ONU, the OLT can set different pre-allocation equalization delays for the ONUs connected to different optical relay devices, so that the OLT only opens the discovery window adapted to the specific optical relay device in the registration process of the ONU, and the adapted discovery window is smaller than the discovery window opened by the OLT without distinction for all ONUs, thereby reducing the uplink delay jitter in the optical communication network.

[0111] S406. The OLT 41 sends a discovery message 0 to the optical relay device 42.

[0112] Corresponding to the process of S406, the optical relay device 42 receives the discovery message 0 sent by the OLT 41.

[0113] The discovery message 0 is also called a standard discovery message. The discovery message 0 carries standard SN(Request) window opening authorization information, which is used to indicate the discovery window opened by the OLT 41 for any optical network device to be online.

[0114] In the case where the OLT not only directly connects the optical relay device, but also directly connects other optical network devices, if the other optical network devices do not need to communicate with the OLT through the optical relay device, these other optical network devices can send the SN of the other optical network device to the OLT through the standard discovery message sent by the OLT, so that the OLT allocates a registration identifier to the other optical network device according to the SN and performs the registration process of the other optical network device.

[0115] In this embodiment, the OLT 41 opens the discovery window for the ONU connected through the optical relay device, and therefore the standard SN(Request) window opening authorization information carried by the discovery message 0 is not applicable to the ONU 43. In order to enable the ONU 43 to register smoothly, two optional implementation manners are provided as follows.

[0116] ​In the first optional implementation, after the optical relay device 42 receives the discovery message 0 sent by the OLT 41, the optical relay device 42 deletes the standard SN (Request) windowing authorization information in the discovery message 0 to obtain an invalid message. In addition, the optical relay device 42 sends the invalid message to the next optical network device of the optical relay device 42. In this way, the next optical network device of the optical relay device 42 cannot obtain the standard SN (Request) windowing authorization information in the discovery message 0, and will not perform the registration process within the discovery window indicated by the standard SN (Request) windowing authorization information.

[0117] In the second optional implementation, after the optical relay device 42 receives the discovery message 0 sent by the OLT 41, the optical relay device 42 terminates the transmission process of the discovery message 0 in the optical communication network. Then, the next optical network device of the optical relay device 42 will not receive the discovery message 0, and will not perform the registration process within the discovery window indicated by the standard SN (Request) windowing authorization information.

[0118] In the above two implementations, the next optical network device of the optical relay device will not receive the standard SN (Request) windowing authorization information, and will not report the SN, so as to avoid the problem that the SN cannot be effectively received by the OLT, and to improve the accuracy of the registration process in the optical communication network. The above two optional implementations are only examples provided by the present embodiment, and should not be construed as a limitation on the present application.

[0119] S407. The OLT 41 sends a discovery message 1 to the optical relay device 42, and opens a discovery window for the optical relay device 42.

[0120] Corresponding to the process of S407, the optical relay device 42 receives the discovery message 1 sent by the OLT 41.

[0121] The discovery message 1 carries the specified BWmap information in the foregoing configuration information.

[0122] The size of the discovery window is determined according to the distance between the next optical network device of the optical relay device 42 and the optical relay device 42 (which can also be referred to as the access distance of the next network of the optical relay device). In the present embodiment, the size of the discovery window is determined according to the distance between the optical relay device 42 and the ONU 43.

[0123] For example, if the distance between the optical relay device 42 and the ONU 43 is within the range of 0-40 kilometers (km), the size of the discovery window can be 3 data frame corresponding transmission time slots. In different protocols, the transmission time slot of a single data frame is different, which is not limited in the present application.

[0124] S408. The optical relay device 42 sends a discovery message 2 to the ONU 43 according to the discovery message 1.

[0125] In the optical relay device 42, the optical relay device 42 converts the designated BWmap information in the discovery message 1 into first standard SN Request windowing authorization information, and generates the discovery message 2. Then, the optical relay device 42 sends the discovery message 2 to the ONU 43. The first standard SN (Request) windowing authorization information is used to indicate the discovery window opened by the OLT 41 for the ONU 43. The first standard SN (Request) windowing authorization information and the standard SN (Request) windowing authorization information carried in the discovery message 0 have the same format, and are different in that the values contained in the first standard SN (Request) windowing authorization information and the standard SN (Request) windowing authorization information carried in the discovery message 0 are different. The discovery window indicated by the first standard SN (Request) windowing authorization information is consistent with the discovery window opened by the OLT 41 in S407.

[0126] The discovery message 1 and the discovery message 2 have the same format, and both carry information indicating that the next optical network device of the optical relay device 42 starts the registration process. For example, the discovery message 1 and the discovery message 2 are used to indicate that the ONU 43 reports the SN of the ONU 43. For example, the ONU 43 sends the SN information of the ONU 43 to the OLT 41 in response to the overhead message received, and specifically, the transmission process of the SN information needs to be forwarded by the optical relay device 42.

[0127] The discovery message 1 and the discovery message 2 are different in that the contents contained in the windowing authorization information field in the two discovery messages are different. The discovery message 1 carries the designated BWmap information, and the discovery message 2 carries the standard SN Request windowing authorization information generated based on the designated BWmap information.

[0128] In the embodiment, the standard SN Request windowing authorization information carried in the discovery message 2 received by the ONU is not the windowing authorization information generated by the OLT based on the standard BWmap information, but the windowing authorization information generated by the optical relay device based on the specified BWmap information. Since the discovery window corresponding to the specified BWmap information is smaller than the discovery window corresponding to the standard BWmap information, the ONU can only implement the registration process of the ONU in the smaller discovery window, that is, in the discovery stage of the SN, the discovery window opened by the OLT for the next optical network device of the optical relay device is smaller than the standard discovery window, the service interruption time of other ONUs connected to the OLT is shortened, which is beneficial to reduce the uplink delay jitter of the optical communication network and improve the communication stability of the optical network devices in the optical communication network.

[0129] S409. The ONU 43 sends a response message 1 to the optical relay device 42 in response to the discovery message 2.

[0130] Corresponding to the process of S409, the optical relay device 42 receives the response message 1 sent by the ONU 43.

[0131] The response message 1 carries the SN of the ONU 43, which is used to uniquely identify the ONU 43 in the optical communication network. The response message 1 can also be referred to as an SN message, an SN response, an SN response message, or an SN response packet, etc., which is not limited in the present application.

[0132] In the embodiment, the process of sending the response message 1 by the ONU 43 can be implemented based on the optical parameters carried in the foregoing overhead message 2. Next, taking the ONU 310 in the structure of Figure 3 In the embodiment, the process of sending the response message 1 by the ONU 43 can be implemented based on the optical parameters carried in the foregoing overhead message 2. Next, taking the ONU 310 in the structure of

[0133] Step 1, the ONU MAC 311 in the ONU 310 sends an adjustment instruction to the ONU PHY 312: adjust the bias current (Ibias) according to the optical parameters, so that the adjusted Ibias is the threshold current (IT) in the optical parameters; and turn off the modulation current (Imod) and turn off Tx_En. For example, the threshold current is 5 milli ampere (mA), 10 mA or other values, etc.

[0134] Step 2, after the laser 313 is stabilized, the ONU MAC 311 sends information of a specific frequency through Tx_En; and the laser 313 turns on and off the optical port without stopping, generates an optical signal corresponding to the information of the specific frequency, and sends the generated optical signal to the ONU 320.

[0135] The specific frequency information is the optical parameter carried in the aforementioned overhead message 2, and the response message carries the registration identifier corresponding to the ONU 310.

[0136] For example, the maximum power of the optical signal generated in step 2 is -23.4 decibel-milliwatts (dBm), and the minimum power is -45.8 dBm.

[0137] In this embodiment, the index of the power of the optical signal can be obtained by the following formula 1.

[0138] dBm = 10*log(P / 1mW) Formula 1

[0139] Wherein, P represents the power value in watts.

[0140] Correspondingly, after the OLT receives the optical signal in the aforementioned step 2, the photodetector (such as the photodetector in the OLT) in the OLT performs photoelectric conversion on the received optical signal to obtain an electrical signal; then, the signal processing module (such as the signal processing module in the OLT) in the OLT processes the electrical signal obtained by photoelectric conversion to obtain a bit stream corresponding to the response message. Figure 3 Figure 3

[0141] S410. The optical relay device 42 sends a response message 2 to the OLT 41 according to the response message 1.

[0142] Corresponding to the process of S410, the OLT 41 receives the response message 2 sent by the optical relay device 42.

[0143] The response message 2 also carries the SN of the ONU 43.

[0144] In this example, the response message 2 and the aforementioned response message 1 are both optical signals, and the difference between the response message 2 and the response message 1 is that the optical signal after the SN of the ONU 43 in the response message 1 will continue to be transmitted, while the optical signal after the SN of the ONU 43 in the response message 2 will be set as an invalid optical signal, or the optical relay device 42 will terminate the transmission process of the optical signal after the SN of the ONU 43 in the response message 2. Wherein, the optical relay device 42 will set the optical signal after the SN of the ONU 43 in the response message 2 as an invalid optical signal, which can include that the optical relay device 42 sets the optical signal as an optical signal of a preset frequency, etc.

[0145] In this way, for the SN reporting process of the ONU to the OLT, the optical signal after the SN in the response message can not be transmitted or be transmitted as an invalid optical signal, so that the OLT does not need to process this part of the optical signal, reducing the consumption of processing resources in the OLT. ​​

[0146] S411. The OLT 41 sends a registration identifier and a ranging request message to the optical relay device 42 according to the SN carried in the response message 2.

[0147] Corresponding to the process of S411, the optical relay device 42 receives the registration identifier and the ranging request message sent by the OLT 41.

[0148] Exemplarily, the registration identifier is a registration identifier allocated by the OLT 41 to the ONU 43 according to the SN of the ONU 43. For example, the registration identifier is an identification (ID) of the ONU 43, which is denoted as: ONU ID 1. The registration identifier is registration information required by the ONU in the process of going online. In the communication process between the ONU 43 and the OLT 41, the OLT 41 uniquely identifies the ONU 43 according to the ONU ID 1, avoids forwarding data sent to the ONU 43 to other ONUs, and thus improves the communication accuracy between the ONU 43 and the OLT 41.

[0149] In some optional implementation manners, the registration identifier can also be an ID of other types of home optical network devices, such as an ID of a single family unit (SFU) (abbreviated as: SFU ID), an ID of a home gateway unit (HGU) (abbreviated as: HGU ID), or an ID of a single business unit (SBU) (abbreviated as: SBU ID), and the like. In the text of the present application, various embodiments are described by taking the ONU ID as an example, but this should not be understood as the registration identifier provided in the present application only refers to the ONU ID.

[0150] Exemplarily, the ranging request message includes the registration identifier (such as the ONU ID 1) of the ONU 43.

[0151] In the embodiment, the OLT 41 can also start a ranging window for the ONU 43, and the size of the ranging window can also be determined according to the access distance between the ONU 43 and the optical relay device 42. The implementation manner of the ranging window is similar to that of the discovery window, which is not described herein.

[0152] S412. The optical relay device 42 sends the registration identifier and the ranging request message of the ONU 43 to the ONU 43.

[0153] Corresponding to the process of S412, the ONU 43 receives the registration identifier and the ranging request message of the ONU 43 sent by the optical relay device 42.

[0154] The ranging request message is used to instruct the ONU 43 to perform a ranging process of the ONU 43 according to the received registration identifier.

[0155] S413. The ONU 43 sends a ranging message to the optical relay device 42 according to the registration identifier of the ONU 43 in response to the ranging request message.

[0156] Corresponding to the process of S413, the optical relay device 42 receives the ranging message sent by the ONU 43.

[0157] The ranging message carries the registration identifier of the ONU 43. In some possible examples, the ranging message 1 can also be referred to as a first ranging message or other names.

[0158] S414. The optical relay device 42 sends the ranging message in S413 to the OLT 41.

[0159] Corresponding to the process of S414, the OLT 41 receives the ranging message sent by the optical relay device 42.

[0160] S415. The OLT 41 sends a response message to the optical relay device 42 in response to the ranging message.

[0161] Corresponding to the process of S414, the optical relay device 42 receives the response message sent by the OLT 41.

[0162] The response message is used to instruct the ONU 43 to adopt an equalization delay for communication in the optical communication network, and the equalization delay indicates a channel to be adopted by the ONU 43 for implementing service data communication after the ONU 43 accesses the optical communication network through the OLT 41.

[0163] It can be understood that, in a plurality of optical network devices accessing the optical communication network through the OLT 41, different optical network devices adopt different channels, that is, different equalization delays are adopted by different ONUs, which is beneficial to avoid a case that different ONUs occupy the same channel to cause errors in service data communication, and improve communication accuracy between the optical network devices in the optical communication network.

[0164] S416. The optical relay device 42 sends the response message in S415 to the ONU 43.

[0165] Corresponding to the process of S416, the ONU 43 receives the response message sent by the optical relay device 42.

[0166] In the embodiment, the discovery window opened by the OLT is determined according to the distance between the optical relay device and the next optical network device of the optical relay device, and the OLT has configured the optical relay device with the specified BWmap information, so that the OLT does not need to open a large discovery window when performing the registration process of the next optical network device of the optical relay device, but only needs to open a discovery window suitable for the aforementioned next optical network device.

[0167] Therefore, the OLT only needs to open a small discovery window in the discovery process of the SN, the time slot corresponding to the small discovery window is reduced, the service interruption time of other optical network devices in communication with the OLT is shortened, which is beneficial to reduce the uplink delay jitter of the optical communication network and improve the communication stability of the optical communication network.

[0168] In some optional implementations, the ONU to be online is also referred to as other ONUs (such as the ONU 44) or other optical relay devices, and the registration process of the ONUs and the optical relay devices can refer to the registration process of the ONU 43 provided in the embodiment, which will not be described herein.

[0169] The beneficial effects of the registration method provided in the application will be exemplarily described below with reference to the accompanying drawings, such as Figure 5 as shown in Figure 5 the comparison diagrams of different registration methods provided in the application.

[0170] In Figure 5 cases 1 and 2, each data frame includes a downstream physical synchronization block (PSBd) and a physical layer frame (PHY frame). The PSBd is used to provide functions such as lock synchronization and frame delimiting, and the PHY frame is used to carry the payload part in the data frame.

[0171] As Figure 5Case 1 in the table, the transmission distance between the OLT and the ONU is 20km, and the registration process of the ONU on the OLT includes: 1, the OLT sends overhead information carrying standard BWmap information to the ONU; 2, the ONU responds to the received overhead information, and sends a response message to the OLT, wherein the response time of the ONU is T11; 3, the OLT receives the response message sent by the ONU, and sends a discovery message to the ONU to start the registration process of the ONU on the OLT. Wherein, T12 is the response time after the ONU receives the discovery message, T13 is the start time of the ONU performing the SN discovery stage, and T14 is the random time between the ONU responding to the discovery message and sending SN. It is worth noting that, taking the equalization time Teqd = 236us between the OLT sending the overhead message and the ONU sending SN as an example, the OLT needs to open a silence window (discovery window) of at least 250us to meet the demand of the OLT for the SN discovery stage of the ONU. Thus, due to the opening of the discovery window by the OLT, there is an uplink delay jitter of at least 250us between the OLT and the ONU.

[0172] As Figure 5 Case 2 in the table, the transmission distance between the OLT and the ONU is 120km, and the registration process of the ONU on the OLT is the same as that of Case 1. Wherein, T21 is the response time of the ONU receiving the overhead message, T22 is the response time of the ONU receiving the discovery message, T13 is the start time of the ONU performing the SN discovery stage, and T14 is the random time between the ONU responding to the discovery message and sending SN. The difference between Case 2 and Case 1 is that the distance is farther, and the discovery window opened by the OLT is 1250us. Further, due to the opening of the discovery window by the OLT, there is an uplink delay jitter of at least 1250us between the OLT and the ONU.

[0173] In combination with Figure 5 Cases 1 and 2, in the case of increasing distance between the ONU and the OLT, the OLT opens the discovery window for all ONUs to be online without distinction, which leads to rapid increase of uplink delay jitter of other ONUs connected to the OLT, increase of interruption time of each service in the optical communication network, and decline of communication performance of the optical communication network.

[0174] Compared with the prior art, the registration method provided by the present application can reduce the uplink delay jitter, as Figure 5 Case 3 in the table, each data frame includes: a downlink physical control block (PCBd) and a payload, as Figure 5The three data frames in the figure respectively include: load N, load N+1 and load N+2. The PCBd can be used to provide lock synchronization, timing and dynamic bandwidth allocation and the like. More details about the PCBd can be referred to the general description, which will not be repeated here.

[0175] The transmission distance between the OLT and the ONU is 120km, and the registration process of the ONU at the OLT includes: 1, the OLT sends a discovery message to the ONU through the optical relay device, the content and implementation of the discovery message can be referred to the description of the discovery message 1 and the discovery message 2, the ONU feeds back the SN of the ONU to the OLT in response to the discovery message. 2, the OLT receives the SN sent by the ONU, allocates a registration identifier (ONU ID=254) for the ONU and opens a ranging window, the ONU sends a ranging message to the OLT through the optical relay device according to the received registration identifier and the ranging request message. 3, the OLT responds to the ranging message and allocates an equalization delay for the ONU, and sends the equalization delay to the ONU in the format of a Ranging message. More details about case 3 can be referred to the description of the foregoing Figure 4 , which will not be repeated here. In combination with the content of Figure 5 , T31 is the propagation delay, T11=0.1us; T32 is the ONU response time; Eqd1 is the pre-allocated equalization delay of the ONU; T33 is the random time between the ONU responding to the discovery message and sending the SN; Tstart is the start time in the standard SN (Request) window authorization information, Tstop is the end time in the standard SN (Request) window authorization information; T34 is the propagation delay between the ONU sending the SN and the OLT receiving the SN. In combination with the foregoing Figure 4 , the discovery window opened by the OLT for the ONU is associated with the distance between the ONU and the optical relay device, therefore, the discovery silence window opened by the OLT only needs to be 250us, which is much smaller than the silence window in case 2, thereby reducing the uplink delay jitter in the PON extended network.

[0176] It can be understood that, in order to realize the functions in the foregoing embodiments, the ONU, the OLT and the optical relay device include corresponding hardware structures and / or software modules for performing various functions. Those skilled in the art should easily realize that, in combination with the units and method steps of the examples described in the embodiments disclosed in the present application, the present application can be realized in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the form of hardware or computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0177] The registration method provided by the embodiment is described in detail above. Figures 1 to 5 The registration device provided by the embodiment is described below. Figure 6 The registration device provided by the embodiment is described below.

[0178] Figure 6 The registration device provided by the embodiment is described below. Figure 1 The registration device 600 can be used to implement the functions of any one of the ONUs in the above method embodiments, and thus can also achieve the beneficial effects of the above method embodiments. In the embodiment, the registration device 600 can be an optical network device 121, an optical relay device 122, another optical network device or optical relay device as shown in FIG. 1, or any one of the optical relay devices or OLTs shown in subsequent figures, and can also be a module (such as a chip) applied to an optical relay device or OLT.

[0179] As shown in FIG. 6, the registration device 600 includes a transceiver module 610 and a processing module 620. The transceiver module 610 and the processing module 620 can cooperatively implement each step in the above method embodiments. For more detailed descriptions of the transceiver module 610 and the processing module 620, reference can be made to the descriptions of the optical relay devices or OLTs in the above method embodiments, which will not be repeated here. Figure 6

[0180] When the registration device implements the registration method shown in any one of the above figures by software, the registration device and each unit thereof can also be a software module. The processor can be a central processing unit (CPU), a specific application integrated circuit (ASIC) implementation, or a programmable logic device (PLD), which can be a complex programmable logic device (CPLD), a field programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0181] For more detailed descriptions of the registration device, reference can be made to the descriptions of the above embodiments, which will not be repeated here. It can be understood that the registration device shown in the above figures is only an example provided by the embodiment, and the registration device can include more or fewer units according to the ranging process or service, which is not limited in the present application.​

[0182] When the registration device is implemented by hardware, the hardware can be implemented by a processor or a chip system. The chip system includes one or more chips, and each chip includes interface circuitry and control circuitry. The interface circuitry is configured to receive data from other devices outside the chip and transmit the data to the control circuitry, or send data from the control circuitry to other devices outside the chip.

[0183] The control circuitry and the interface circuitry are configured to implement the method of any possible implementation of the above-described embodiments by logic circuitry or by executing software code instructions. The benefits can be understood with reference to the description of any of the above-described embodiments, which will not be repeated here.

[0184] It can be understood that the processor in the embodiments of the present application can be a CPU, and can also be other general-purpose processors, digital signal processors (DSP), ASICs, FPGAs or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor can be a microprocessor or any conventional processor.

[0185] In addition, Figure 6 The registration device 600 shown can also be implemented by an optical network device, such as an optical line terminal (OLT) or an optical network unit (ONU). Figure 7 As shown, Figure 7 A structure diagram of an optical network device provided by the present application is shown. The optical network device 700 includes a memory 710 and at least one processor 720. The processor 720 can implement the registration method provided by the above-described embodiments. The memory 710 is configured to store software instructions corresponding to the above-described registration method. As an optional implementation manner, in terms of hardware implementation, the optical network device 700 can be a chip or a chip system encapsulating one or more processors 720. For example, when the optical network device 700 is used to implement the method steps in the above-described embodiments, the processor 720 included in the optical network device 700 executes the steps of the above-described method and possible sub-steps thereof. In an optional case, the optical network device 700 can further include a communication interface 730, which can be configured to receive and transmit data. For example, the communication interface 730 is configured to receive a ranging message, or transmit a ranging message, etc. The communication interface 730 can be implemented by interface circuitry included in the optical network device 700.

[0186] In the embodiments of the present application, the communication interface 730, the processor 720 and the memory 710 can be connected through a bus 740, which can be divided into an address bus, a data bus, a control bus, etc. The bus 740 can be a Peripheral Component Interconnect Express (PCIe) bus, or an extended industry standard architecture (EISA) bus, a unified bus (Ubus or UB), a compute express link (CXL), a cache coherent interconnect for accelerators (CCIX), etc.

[0187] It is worth noting that the optical network device 700 can also perform the functions of the registration apparatus 600 shown, which will not be described here. Figure 6 The functions of the registration apparatus 600 shown can also be performed by the optical network device 700, which will not be described here.

[0188] The optical network device 700 provided by the present embodiment can be any of the above OLTs, or other optical network devices with data processing functions, which are not limited by the present application. For example, the optical network device 700 can be any of the foregoing optical network devices, such as the OLT 41 or the optical network device 121, etc.

[0189] In addition, Figure 6 The registration apparatus 600 shown can also be implemented through an optical relay device. When the registration apparatus 600 is implemented through an optical relay device, the hardware implementation of the optical relay device can refer to the related description of the optical relay device 700, which will not be described here. Figure 3

[0190] ​The steps of the methods in embodiments of the application can also be implemented in software instructions executed by a processor. The software instructions can be comprised by respective software modules, which can be stored in a memory such as a random access memory (RAM), a flash memory, a read-only memory (ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically EPROM (EEPROM), a register, a hard disk, a floppy disk, a CD-ROM, or any other form of storage medium well known to the skilled in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Of course, the storage medium can be a component of the processor. Suitable processors for the execution of software instructions include, by way of example, both general and special purpose microprocessors. The software instructions can be written in any suitable programming language such as, for example, C. The software instructions can be embodied on one or more software modules, which can be executed by the processor. The software instructions can also be stored in any other volatile or non-volatile storage medium well known to the skilled in the art.

[0191] The application also provides a communication system comprising optical fibers, one master network device and at least one slave network device. The optical fibers are used to connect the network devices. The network devices can be the ONUs described above.

[0192] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer programs or instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are performed. The computer can be a general purpose computer, a special purpose computer, a computer network, a network device, a user equipment or other programmable apparatus. The computer programs or instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer programs or instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center through wired or wireless manner. The computer readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center and the like integrated with one or more available media. The available media can be a magnetic medium, for example, a floppy disk, a hard disk, a magnetic tape; or an optical medium, for example, a digital video disc (digital video disc, DVD); or a semiconductor medium, for example, a solid state disk (solid state drive, SSD).

[0193] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed in the present application, and these modifications or replacements should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for activating an Optical Network Unit (ONU), characterized in that, The method includes: If the ONU achieves downlink synchronization, the ONU enters the configuration file learning state; The ONU obtains multiple uplink wavelength options from the received data stream; the received data stream includes downlink physical frames, the downlink physical frames include an Operation Control Body (OC body), the OC body includes the multiple uplink wavelength options; or, the received data stream includes a burst profile message, the burst profile message includes the multiple uplink wavelength options. If the ONU supports at least one of the multiple uplink wavelength options, the ONU enters the serial number state from the configuration file learning state.

2. The method according to claim 1, characterized in that, After the ONU enters the serial number state, the method further includes: If the ONU receives a sequence number authorization, the ONU sends sequence number management and maintenance information, wherein the sequence number authorization is used to indicate that the ONU is allowed to join or resume entering the passive optical network, and the sequence number management and maintenance information is used to indicate the sequence number and random delay of the ONU.

3. The method according to claim 2, characterized in that, After the ONU sends the serial number management and maintenance information, the method further includes: After receiving the ONU-ID, the ONU enters the ranging state, wherein the ONU-ID is used to uniquely identify the ONU in the passive optical network.

4. The method according to claim 3, characterized in that, After the ONU enters the ranging state, the method further includes: The ONU receives equalization delay information and adjusts the uplink clock based on the equalization delay information to complete activation.

5. The method according to any one of claims 1-4, characterized in that, The ONU implements downlink synchronization, specifically including: The downlink synchronization state machine of the ONU enters the synchronization state from the pre-synchronization state.

6. The method according to any one of claims 1-4, characterized in that, After the ONU enters the configuration file learning state, the method further includes: If the ONU loses downlink synchronization, the ONU returns from the configuration file learning state to the synchronization off state.

7. The method according to claim 6, characterized in that, The loss of downlink synchronization of the ONU specifically includes: The downlink synchronization state machine of the ONU enters the search state from the pre-synchronization state.

8. The method according to any one of claims 1-4, characterized in that, The multiple wavelength options are three wavelength options: the first wavelength option is 1260nm~1280nm, the second wavelength option is 1290nm~1310nm, and the third wavelength option is 1284nm~1288nm.

9. The method according to claim 8, characterized in that, The method is performed on an activation wavelength that is different from the plurality of uplink wavelength options.

10. An optical network unit, characterized in that, include: Interface and processor, wherein the processor is used for: If downlink synchronization is achieved, the system will enter the configuration file learning state. Multiple uplink wavelength options are obtained from the data stream received through the interface; the received data stream includes downlink physical frames, the downlink physical frames include an Operation Control Body (OC body), the OC body includes the multiple uplink wavelength options; or, the received data stream includes a burst profile message, the burst profile message includes the multiple uplink wavelength options. If the optical network unit supports at least one of the plurality of uplink wavelength options, it transitions from the configuration file learning state to the serial number state.

11. The optical network unit according to claim 10, characterized in that, The processor is used for: After entering the sequence number state, if a sequence number authorization is received, sequence number management and maintenance information is sent. The sequence number authorization is used to indicate that the optical network unit is allowed to join or resume entering the passive optical network, and the sequence number management and maintenance information is used to indicate the sequence number and random delay of the optical network unit.

12. The optical network unit according to claim 11, characterized in that, The processor is used for: After sending the serial number management and maintenance information, if an ONU-ID is received, the system enters the ranging state, whereby the ONU-ID is used to uniquely identify the optical network unit in the passive optical network.

13. The optical network unit according to claim 12, characterized in that, The processor is used for: After entering the ranging state, the system receives equalization delay information through the interface and adjusts the uplink clock based on the equalization delay information to complete the activation.

14. The optical network unit according to any one of claims 10-13, characterized in that, The processor is specifically used for: If the downlink synchronization state machine transitions from the pre-synchronization state to the synchronization state, it enters the configuration file learning state.

15. The optical network unit according to any one of claims 10-13, characterized in that, The processor is also used for: After entering the configuration file learning state, if downlink synchronization is lost, the system will return from the configuration file learning state to the synchronization off state.

16. The optical network unit according to claim 15, characterized in that, The processor is specifically used for: After entering the configuration file learning state, if the downlink synchronization state machine enters the search state from the pre-synchronization state, it returns from the configuration file learning state to the closed synchronization state.

17. The optical network unit according to any one of claims 10-13, characterized in that, The multiple wavelength options are three wavelength options: the first wavelength option is 1260nm~1280nm, the second wavelength option is 1290nm~1310nm, and the third wavelength option is 1284nm~1288nm.

18. A communication system, characterized in that, include: An optical line terminal and at least one optical network unit as described in any one of claims 10 to 17, wherein the optical line terminal is connected to the at least one optical network unit.

Images