Passive optical network architecture, data transmission method and master device

Abstract

The embodiment of the invention provides a passive optical network architecture, a data transmission method and a master device, the architecture comprises FTTH optical line terminals, master devices and FTTR slave devices, each FTTH optical line terminal is connected with at least one master device, each master device is connected with at least one FTTR slave device, the master devices are connected with the FTTR slave devices, and the FTTR slave devices are connected with the FTTH optical line terminals. And the forwarding module is used for establishing a forwarding channel between the FTTH optical line terminal and the FTTR slave equipment and carrying out equal-time-delay forwarding on uplink and downlink frames between the FTTH optical line terminal and the FTTR slave equipment through the forwarding channel. According to the embodiment of the invention, the FTTR network and the FTTH network can be integrated into a whole, the master device and the FTTR slave device are scheduled and managed in a unified manner through the FTTH optical line terminal, and a passive optical network in which the FTTH and the FTTR cooperate with each other is logically formed.

Description

Technical Field

[0001] The present application relates to the field of passive optical networks, and in particular to a passive optical network architecture, a data transmission method and a main device. Background Art

[0002] Fiber to the Room (FTTR) is a fiber access technology that aims to extend the fiber network into the user's room to provide users with high-speed, stable and wider network connections. With the continuous development of communication technology, FTTR has gradually entered the stage of large-scale deployment and its standardization has gradually matured.

[0003] FTTR is similar to Fiber to the Home (FTTH), and uses a point-to-multipoint network topology. FTTR is composed of a main device (Main FTTR Unit, MFU) connected to multiple slave devices (Sub FTTR Unit, SFU) through an indoor optical distribution network (Indoor Fibre Distribution Network, IFDN). FTTH is composed of an optical line terminal (Optical Line Terminal, OLT) connected to multiple optical network units (Optical Network Unit, ONU) through an optical distribution network (Optical Distribution Network, ODN).

[0004] Figure 1 The schematic diagram of the architecture of FTTH network and FTTR network is as follows: Figure 1 As shown in the figure, when the FTTH network and the FTTR network are networked together, the ONU in the FTTH network is replaced by the main device, and the main device consists of two parts: the FTTH ONU and the FTTR OLT. In the current networking application, the FTTH ONU and the FTTR OLT in the main device need to use upper layer protocols such as Ethernet protocols to achieve mutual service exchange. The FTTR network and the FTTH network are two independent networks. Each network is managed and resource allocated by its own OLT, which cannot achieve collaboration, low-latency service transmission, and is not conducive to unified management and operation of operators.

[0005] In summary, there is no good solution to the above technical problems. Summary of the invention

[0006] The embodiments of the present application provide a passive optical network architecture to at least solve the problem in the related art that FTTR and FTTH cannot be networked collaboratively.

[0007] According to one embodiment of the present application, a passive optical network architecture is provided, the architecture comprising: an FTTH optical line terminal, a master device and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein the master device is used to establish a forwarding channel based on an optical layer standard between the FTTH optical line terminal and the FTTR slave device, and to perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

[0008] According to another embodiment of the present application, a data transmission method is also provided, which is applied to a passive optical network architecture, wherein the architecture includes: an FTTH optical line terminal, a master device, and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein the method includes: forwarding a downlink frame iso-delay from the FTTH optical line terminal to the FTTR slave device through a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and forwarding an uplink frame iso-delay from the FTTR slave device to the FTTH optical line terminal through the forwarding channel, wherein the forwarding channel is established by the master device.

[0009] According to another embodiment of the present application, a master device is also provided, which is applied to a passive optical network architecture, wherein the architecture includes: an FTTH optical line terminal, a master device, and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein the master device is used to establish a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and to perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

[0010] In the embodiment of the present application, the master device realizes equal-latency forwarding channel by working in the optical layer standard, and does not need to realize forwarding through the upper layer protocol. The equal-latency forwarding channel between the FTTH optical line terminal and the FTTR slave device is established, and the FTTR network and the FTTH network can be integrated into a whole, realizing the logical integration of FTTH and FTTR. The slave device and the master device belong to the ONU under the OLT in the device logic. FTTR is an extension of FTTH. The FTTH optical line terminal uniformly dispatches resources for multiple master devices and FTTR slave devices in different FTTR networks, which can realize low-latency service transmission, and the FTTH OLT can directly manage the FTTR slave device, logically forming a passive optical network in which FTTH and FTTR cooperate with each other. The FTTR master device can independently build a home internal network with the FTTR slave device. By modifying or replacing the FTTH home gateway device as the master device and deploying the indoor optical distribution network of FTTR, the slave device can be directly accessed, and then the configuration and service of SFU can be opened on the FTTH management platform. According to business needs, the FTTR slave device can also establish an equal-delay forwarding channel, so that the downstream device of the FTTR slave device also becomes an extension of the FTTR network and FTTH network, and logically becomes a network with the FTTH network and FTTR network. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the architecture of the FTTH network and the FTTR network;

[0012] Figure 2 It is a schematic diagram of the structure of a passive optical network architecture according to an embodiment of the present application;

[0013] Figure 3 This is a schematic diagram of the BWmap structure of the XG-PON standard;

[0014] Figure 4 This is a schematic diagram of the structure of BWmap for GPON standard;

[0015] Figure 5 It is a schematic diagram of the structure of the XGEM frame of the XG-PON standard;

[0016] Figure 6 This is a schematic diagram of the structure of the GEM frame of the GPON standard;

[0017] Figure 7 It is a schematic diagram of the structure of the GPON standard uplink burst message;

[0018] Figure 8 It is a schematic diagram of the structure of the XG-PON standard uplink burst message;

[0019] Fig. 9is a flowchart of a data transmission method according to an embodiment of the present application;

[0020] Fig.10 is a schematic diagram of the structure of a passive optical network architecture according to an embodiment of the present application;

[0021] Fig.11 is a schematic structural diagram of a passive optical network architecture according to another embodiment of the present application;

[0022] Fig.12 It is a structural diagram of a passive optical network architecture in another embodiment of the present application. DETAILED DESCRIPTION

[0023] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0025] Figure 2 is a schematic diagram of a passive optical network architecture according to an embodiment of the present application. Figure 2 As shown, the architecture includes:

[0026] FTTH optical line terminal 22 , master device 24 and FTTR slave device 26 .

[0027] In this embodiment, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices.

[0028] In this embodiment, the master device is used to establish a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

[0029] In this embodiment, the master device may forward the downlink frame from the FTTH optical line terminal to the FTTR slave device through the forwarding channel, and forward the uplink frame from the FTTR slave device to the FTTH optical line terminal through the forwarding channel.

[0030] In this embodiment, the Optical Line Terminal (OLT) and the Optical Network Unit (ONU) are both common devices in the optical fiber access network. The OLT is usually responsible for managing and controlling the entire optical fiber access network, mainly managing and controlling the Optical Network Unit (ONU). The ONU is responsible for the access and communication of user terminal devices.

[0031] In this embodiment, fiber to the room (FTTR) is an extension of fiber to the home (FTTH). The master device may include an FTTH optical network unit (ONU) in FTTH, and the FTTH optical line terminal and the master device may realize FTTH networking. Of course, the master device may not include the FTTH ONU, and only provide an equal-delay forwarding channel for the OLT and the slave device. The slave device is the FTTR ONU in FTTR, and the slave device and the master device may realize FTTR networking.

[0032] In this embodiment, the FTTH optical line terminal (OLT) can uniformly manage the network of FTTH and FTTR, and uniformly schedule the resources of FTTH ONU and FTTR ONU. The embodiment of the present application can also be used to extend FTTR, by establishing a forwarding channel, the FTTR OLT uniformly manages the downstream devices of the FTTR slave device.

[0033] In the embodiment of the present application, by establishing a forwarding channel between the FTTH optical line terminal and the FTTR slave device, the FTTR network and the FTTH network can be integrated into a whole, and the FTTH ONU and the FTTR OUN are uniformly scheduled and managed through the FTTH OLT, so as to logically form a passive optical network in which FTTH and FTTR cooperate with each other, thereby solving the problem that FTTR and FTTH in the related technology cannot be networked collaboratively.

[0034] In some embodiments, the master device is used to identify the target device identifier of the downlink frame, filter the downlink frame according to the target device identifier, and delay forwarding the downstream downlink frame or broadcast downlink frame belonging to the downstream device of the master device to the downstream device of the master device, wherein the downstream device of the master device is an FTTR slave device directly connected to the master device.

[0035] In some embodiments, the downlink frame includes at least one of the following: a physical layer operations, administration and maintenance (PLOAM) message; a bandwidth mapping (Bandwidth Map, BWmap) entry; and a passive optical network encapsulation frame.

[0036] In this embodiment, the BWmap may include multiple BWmap entries, and each BWmap entry corresponds to an allocation structure (8 bytes) in the BWmap.

[0037] In an exemplary embodiment, the passive optical network encapsulation frame includes a Gigabit Passive Optical Network Encapsulation Method (GPONEncapsulation Method, referred to as GEM) frame, a 10 Gigabit Passive Optical Network Encapsulation Method (XG-PONEncapsulation Method, referred to as XGEM) frame, and the like.

[0038] In some embodiments, the master device is used to identify the target device of the PLOAM message according to the slave device identifier SFU ID or the optical network unit identifier ONU ID in the PLOAM message when the downlink frame is a PLOAM message; and / or, to identify the target device of the BWmap entry according to the allocation identifier Alloc-ID in the BWmap entry when the downlink frame is a BWmap entry; and / or, to identify the target device of the passive optical network encapsulation frame according to the port identifier Port ID in the passive optical network encapsulation frame when the downlink frame is a passive optical network encapsulation frame.

[0039] In some embodiments, the master device is used to convert an original standard message into a target standard message when the original standard is different from the target standard, wherein the original standard and the target standard are respectively an optical network specification, and the optical network specification includes an optical network specification used for FTTH and FTTR, such as passive optical network specifications GPON, symmetric GPON, XG-PON, XGS-PON, 50G-PON, and passive optical network specifications to be defined in the future. Passive optical network specifications can be used for both FTTH and FTTR, such as FTTR specifications such as G.fin and CCSA FTTR. When the original standard message is a downlink frame received by the master device from the FTTH optical line terminal, the target standard message is a downlink frame sent by the master device to the FTTR slave device. When the original standard message is an uplink frame received by the master device from the FTTR slave device, the target standard message is an uplink frame sent by the master device to the FTTH optical line terminal.

[0040] In some embodiments, the master device is used to convert multiple fields in the original standard message into multiple fields in the target standard message according to a preset standard conversion rule.

[0041] In an exemplary embodiment, the system conversion rule includes at least one of the following:

[0042] In the case where the first field and the second field are the same, converting the field value of the first field into the field value of the second field, wherein the first field is any field in the original standard message, and the second field is any field in the target standard message;

[0043] If there is no field identical to the first field in the target standard message, adding the first field as a new field to the target standard message;

[0044] If there is no field identical to the second field in the original standard message, deleting the second field from the target standard message;

[0045] When the length of the target standard message is smaller than the length of the original standard message, some fields in the original standard message are deleted.

[0046] In this embodiment, the field contents in the original standard message and the target standard message need to be determined according to the types of the uplink and downlink frames, and the types of the uplink and downlink frames remain unchanged before and after the standard conversion. Exemplarily, the downlink frame may include: PLOAM message, BWmap entry, passive optical network encapsulation frame, and the uplink frame may include: PLOAM message, passive optical network encapsulation frame.

[0047] In some embodiments, the FTTH segment standard includes at least one of the following: GPON standard, symmetric GPON standard, XG-PON standard, XGS-PON standard, 50G-PON standard, and a passive optical network standard defined in the future, wherein the FTTH segment standard is an optical network specification used between the FTTH optical line terminal and the main device.

[0048] In some embodiments, the FTTR segment standard includes at least one of the following: GPON standard, symmetric GPON standard, XG-PON standard, XGS-PON standard, 50G-PON standard, a passive optical network standard defined in the future, G.fin standard, CCSA FTTR standard, wherein the FTTR segment standard is a passive optical network specification used between the master device and the FTTR slave device.

[0049] In this embodiment, the FTTH segment standard and the FTTR segment standard may be the same or different, and this application does not impose any limitation on this.

[0050] In some embodiments, the main device is also used to convert the downlink frame directly from the FTTH segment standard to the FTTR segment standard, or to convert the downlink frame to an intermediate standard, and then convert from the intermediate standard to the FTTR segment standard, wherein the intermediate standard is a network specification other than the optical network specification.

[0051] In some embodiments, the master device is further used to convert the uplink frame directly from the FTTR segment format to the FTTH segment format, or to convert the uplink frame to the intermediate format and then convert from the intermediate format to the FTTH segment format.

[0052] In an exemplary embodiment, the intermediate format may be a network specification of a communication layer, such as Ethernet, Internet Protocol (IP for short), Hypertext Transfer Protocol (HTTP for short), and the like.

[0053] In some embodiments, the master device is used to cache the downlink frame from the FTTH optical line terminal for a first time and then forward it to the FTTR slave device, so that the downlink forwarding delay consumed by the master device each time forwarding the downlink frame remains consistent (of course, in a specific implementation, there may be errors in the downlink forwarding delay in different forwarding processes, which is also allowed), and cache the uplink frame from the FTTR slave device for a second time and then forward it to the FTTH optical line terminal, so that the uplink forwarding delay consumed by the master device each time forwarding the uplink frame remains consistent (of course, in a specific implementation, there may be errors in the uplink forwarding delay in different forwarding processes, which is also allowed).

[0054] In some embodiments, the master device is used to determine the first time and the second time according to the downlink processing time and the uplink processing time when the original standard is the same as the target standard, wherein the original standard and the target standard are respectively an optical network specification.

[0055] In other embodiments, the master device is used to determine the first time and the second time according to the rate of the original standard, the rate of the target standard, the downlink processing time and the uplink processing time when the original standard is different from the target standard.

[0056] In an exemplary embodiment, the FTTH segment standard may adopt the XG-PON standard, with the upstream and downstream rates being 2.5G / 10G respectively, and the FTTR segment standard may adopt the GPON standard, with the upstream and downstream rates being 1.25G / 2.5G respectively. Alternatively, the FTTH segment standard may adopt the XGS-PON standard, with the upstream and downstream rates being 10G / 10G respectively, and the FTTR segment standard may adopt the symmetrical GPON standard, with the upstream and downstream rates being 2.5G / 2.5G respectively. Alternatively, the FTTH segment standard may adopt the XG-PON standard, with the upstream and downstream rates being 2.5G / 10G respectively, and the FTTR segment standard may adopt the G.fin standard, with the upstream and downstream rates being 2.5G / 2.5G respectively.

[0057] In some embodiments, if the original standard rate is slow, the data enters the master device slowly and exits the master device quickly. At this time, the master device must actively cache the original standard data to a certain extent to prevent the target standard from failing to obtain data. This cache degree or size must take into account the size of the original standard frame to ensure that the target standard is prevented from failing to obtain data. If the original standard rate is fast, the target standard takes data slowly, and the data is passively cached in the master device. This cache degree or size must take into account the size of the original standard frame to ensure that the target standard does not have time to take away the data, resulting in a cache overflow. Therefore, in order to determine this cache degree or size, the maximum length of the original standard frame needs to be defined.

[0058] In an exemplary embodiment, the downlink processing time includes at least one of the following:

[0059] The identification time consumed for identifying the downlink frame;

[0060] The filtering time consumed for filtering the downlink frame;

[0061] The conversion time consumed for converting the format of the downlink frame;

[0062] In an exemplary embodiment, the uplink processing time includes at least one of the following:

[0063] The identification time consumed for identifying the uplink frame;

[0064] The conversion time consumed for converting the format of the uplink frame;

[0065] The time consumed for regenerating the burst overhead of the uplink frame.

[0066] In an exemplary embodiment, the identification time consumed for identifying the uplink frame may be that the master device consumes part of the preamble to lock the clock and search for the delimiter to obtain the uplink burst content when identifying the uplink burst message. The master device needs to restore the uplink burst preamble and delimiter when forwarding the uplink burst content to the FTTH optical line terminal. Therefore, when determining the uplink frame buffer time (i.e., the second time), the consumption of this period of time needs to be considered.

[0067] In some embodiments, the master device can appropriately parse the uplink burst to obtain the identity information of the FTTR slave device, or obtain the identity information of the FTTR slave device based on the correspondence between the downlink management information and the uplink burst, thereby establishing a subordinate topology relationship between the master device and the FTTR slave device.

[0068] In some embodiments, the downlink frame includes at least one of the following: a PLOAM message, a BWmap entry, and a passive optical network encapsulation frame; the uplink frame includes at least one of the following: a PLOAM message and a passive optical network encapsulation frame. Depending on the uplink and downlink frame structures, there will be certain differences in the processing time consumed by the uplink and downlink frames before forwarding, as well as the specific methods of identification, filtering, and forwarding.

[0069] In some embodiments, the architecture further includes: a downstream device of a slave device, each of the FTTR slave devices is connected to at least one downstream device of the slave device, wherein the FTTR slave device is used to establish a forwarding channel between the master device and the downstream device of the slave device, and forward the downlink frame and other delays from the master device to the downstream device of the slave device through the forwarding channel, and forward the uplink frame and other delays from the downstream device of the slave device to the master device through the forwarding channel. Through this embodiment, it is possible to further extend the FTTR network, realize integrated networking of multiple layers of networks, and perform unified resource scheduling and network control on optical network units of different levels in the network.

[0070] In the embodiment of the present application, by establishing a forwarding channel between the FTTH optical line terminal and the FTTR slave device, the FTTR network and the FTTH network can be integrated into a whole, and the FTTH optical line terminal can be used to uniformly schedule and manage multiple master devices and FTTR slave devices in different FTTR networks, logically forming a passive optical network in which FTTH and FTTR work together.

[0071] The FTTH segment standard and FTTR standard in this embodiment can be implemented based on different optical network specifications. On this basis, according to the standard differences before and after forwarding and different uplink and downlink frame structures, the master device will also have certain differences in the processing methods of identifying, filtering, and converting uplink and downlink frames. The following takes the GPON standard and the XG-PON standard as examples, and specifically describes the frame structure based on the PLOAM message, BWmap entry, and passive optical network encapsulation frame. However, the present application is not limited to this.

[0072] In implementation mode 1, the FTTH and FTTR segments use the same standard, such as GPON or XG-PON. Except for the listed standards, other standards are not described in detail. The following description is based on the example that both segments use GPON.

[0073] In this embodiment, the master device filters and forwards the management information and services in the downstream direction with equal delay, and filters out the management information and services belonging to the downstream slave devices of the master device, or the broadcast management information and services. The master device only forwards the filtered management information and services to its downstream slave devices (i.e., the downstream devices of the master device), and does not forward the others.

[0074] In an exemplary embodiment, the downlink frame is a PLOAM message, and the master device checks the SFU-ID (slave device identifier) / ONU-ID (optical network unit identifier) ​​in the PLOAM message. If the SFU-ID / ONU-ID is a broadcast SFU-ID / ONU-ID, or the SFU-ID / ONU-ID is an identifier of a slave device downstream of the master device, the master device forwards the PLOAM message to its downstream slave device.

[0075] In an exemplary embodiment, the downlink frame is a BWmap entry, and the master device checks the Alloc-ID (allocation identifier) ​​in the BWmap entry. If the Alloc-ID is a broadcast Alloc-ID, or the Alloc-ID is an identifier of a slave device downstream of the master device, the BWmap entry is forwarded to its downstream slave device. Exemplarily, the master device can also cache these BWmap entries in the downstream direction locally to receive the uplink burst sent by the slave device in the corresponding time slot. The receiving process is similar to the OLT receiving the uplink burst sent by the ONU in the passive optical network, which will not be repeated here.

[0076] In an exemplary embodiment, the downlink frame is a passive optical network encapsulation frame, and the master device checks the Port-ID (port identifier) ​​in the passive optical network encapsulation frame. If the Port-ID is a broadcast Port-ID, or the Port-ID is an identifier of a device downstream of the master device, the master device forwards the passive optical network encapsulation frame to its downstream slave device.

[0077] In this embodiment, the master device performs equal delay forwarding for the services in the upstream direction. The master device receives the upstream burst and transparently forwards it to the OLT (i.e., FTTH optical line terminal). When the master device receives the upstream burst, it needs to consume a certain amount of preamble and receive the upstream burst content by searching for delimitation. When the master device forwards the upstream burst content to the OLT, it needs to restore the upstream burst preamble and delimitation. Therefore, the master device needs to cache the upstream burst content locally, and through caching, the upstream forwarding delay of the master device is kept consistent for all slave devices and all upstream bursts.

[0078] In some embodiments, the master device can appropriately parse the uplink burst to obtain the identity information of the FTTR slave device, or obtain the identity information of the FTTR slave device based on the correspondence between the downlink management information and the uplink burst, thereby establishing a subordinate topology relationship between the master device and the FTTR slave device.

[0079] In some embodiments, the same buffer time can also be introduced in the downlink forwarding process of the master device to keep the downlink forwarding delay of the master device consistent for all downlink frames and all slave devices. Further, for uplink and downlink symmetry, the uplink forwarding delay can be the same as the downlink forwarding delay, but this application does not limit this.

[0080] In the second implementation mode, the FTTH and FTTR sections adopt different standards, and the rate of the FTTR section is not higher than the rate of the FTTH section.

[0081] In an exemplary embodiment, the FTTH segment adopts the XG-PON standard, and the upstream and downstream rates are 2.5G / 10G respectively, and the FTTR segment adopts the GPON standard, and the upstream and downstream rates are 1.25G / 2.5G respectively. Alternatively, the FTTH segment adopts the XGS-PON standard, and the upstream and downstream rates are 10G / 10G respectively, and the FTTR segment adopts the symmetrical GPON standard, and the upstream and downstream rates are 2.5G / 2.5G respectively. Alternatively, the FTTH segment adopts the XG-PON standard, and the upstream and downstream rates are 2.5G / 10G respectively, and the FTTR segment adopts the G.fin standard, and the upstream and downstream rates are 2.5G / 2.5G respectively. In addition to the listed standards, other standards will not be repeated. The following is an example of the FTTH segment adopting the XG-PON standard and the FTTR segment adopting the GPON standard.

[0082] In this embodiment, the master device filters, converts the format, and forwards the management information and services in the downstream direction with equal delay. The master device filters out the management information and services of the downstream device of the master device, or the broadcast management information and services, and forwards the filtered management information and services to its downstream slave devices, and does not forward other information. Before forwarding these management information and services, the master device also needs to perform format conversion, converting these management information and services from the XG-PON format of the FTTH segment to the GPON format of the FTTR segment.

[0083] In an exemplary embodiment, the downlink frame is a PLOAM message, and the master device checks the SFU-ID / ONU-ID in the PLOAM message. If the SFU-ID / ONU-ID is a broadcast SFU-ID / ONU-ID, or the SFU-ID / ONU-ID belongs to a slave device downstream of the master device, the master device converts the XG-PON PLOAM message into a GPON PLOAM message, and forwards the converted PLOAM message to its downstream slave device. It should be noted that the GPON SFU-ID / ONU-ID has a smaller value range than the XG-PON SFU-ID / ONU-ID, and the OLT must comply with the GPON value range when configuring the SFU-ID / ONU-ID for the slave gateway.

[0084] In this embodiment, the original standard message is a downstream XG-PON standard PLOAM message, and the message structure can refer to the standard text G.987.3 formulated by the International Telecommunication Union Telecommunication Standardization Sector (ITU Telecommunication Standardization Sector, referred to as ITU-T), and the target standard message is a downstream GPON standard PLOAM message, and the message structure can refer to ITU-T G.984.3.

[0085] In an exemplary embodiment, the correspondence between the XG-PON downstream PLOAM message and related content and the GPON downstream PLOAM message can be shown in the following Table 1. This embodiment is only described by taking the conversion relationship from the XG-PON downstream PLOAM message to the GPON downstream PLOAM message as an example, and the technicians can also implement the conversion of PLOAM messages of other different standards according to the standard conversion rules and the message structures of different standards, and this application does not limit this.

[0086] Table 1:

[0087]

[0088]

[0089] In an exemplary embodiment, such as the first few messages in Table 1, Assign_ONU-ID PLOAM message, Ranging_Time PLOAM message, etc., for XG-PON PLOAM message content and GPON PLOAM message content that are consistent, only the format needs to be converted. For the message content that needs to be converted, as long as the target standard message can be carried, it is converted.

[0090] In an exemplary embodiment, as shown in Table 1, the XG-PON standard Sleep_Allow PLOAM message, GPON does not have a corresponding PLOAM message, and a corresponding energy-saving function and a corresponding Sleep_Allow (sleep permission) message can be added to the GPON standard. Before the corresponding function is added to GPON, the slave device may temporarily not support the corresponding energy-saving function.

[0091] In an exemplary embodiment, the Change_Power_Level message in the GPON standard in Table 1 has no corresponding message in the XG-PON standard and can be directly cancelled.

[0092] In this embodiment, the XG-PON PLOAM message format is 48 bytes, of which 36 bytes are used to send the message content, and the GPON PLOAM message format is 13 bytes, of which 10 bytes are used to send the message content. For the XG-PON PLOAM message content and the GPON PLOAM message content that are consistent, only the format is converted. For the message content that needs to be converted, as long as the GPON PLOAM message can be carried, it is converted. If the GPON PLOAM message content does not have a corresponding field, or exceeds the GPON PLOAM message content length, it is not necessary to convert.

[0093] Through the embodiments of the present application, the format conversion from XG-PON downstream PLOAM message to GPON downstream PLOAM message can be realized, and then the integrated networking of FTTH segment networks and FTTR segment networks of different formats can be realized.

[0094] In another exemplary embodiment, the downlink frame is a BWmap entry, and the master device checks the Alloc-ID (allocation identifier) ​​in the BWmap entry. If the Alloc-ID is a broadcast Alloc-ID, or the Alloc-ID belongs to a downstream device of the master device, the master device converts the BWmap entry of the XG-PON standard into a BWmap entry of the GPON standard, and forwards the converted BWmap entry to its downstream FTTR slave device. The master device can save these BWmap entries locally for receiving the upstream bursts sent by the corresponding slave device. The receiving process is similar to the OLT receiving the upstream bursts sent by the ONU in the passive optical network, and will not be repeated here. It should be pointed out that the value range of GPON Alloc-ID is smaller than that of XG-PON Alloc-ID, and the OLT must comply with the GPON value range when configuring T-CONT for the slave gateway.

[0095] Figure 3 This is a schematic diagram of the BWmap structure of the XG-PON standard. Figure 3 As shown, the BWmap (bandwidth map) of the XG-PON standard consists of multiple entries or allocation structures (Allocation Structure), each of which contains the following fields:

[0096] Allocation identifier (Alloc-ID), start time (StartTime), grant size (GrantSize), forced wake-up indication (FWI), burst profile (Burst Profile), header error control (HEC), upstream physical layer operation management and maintenance indication (PLOAMu) and upstream dynamic bandwidth reporting indication (DBRu).

[0097] Figure 4 This is a schematic diagram of the structure of the BWmap of the GPON standard. Figure 4 As shown, the BWmap of the GPON standard consists of multiple entries or allocation structures, each of which contains the following fields:

[0098] Allocation ID (Alloc-ID), Flags, Start Time (StartTime), Stop Time (StopTime), Cyclic Redundancy Check (CRC).

[0099] In an exemplary embodiment, the field correspondence between the XG-PON BWmap entry and the GPON BWmap entry may be as shown in Table 2. This embodiment is only described by taking the conversion relationship from the XG-PON standard BWmap entry to the GPON standard BWmap entry as an example, and the technicians may also implement the conversion of BWmap entries of other different standards according to the standard conversion rules and the message structures of different standards, and this application does not limit this.

[0100] Table 2:

[0101]

[0102]

[0103] In an exemplary embodiment, the StopTime in the target standard GPON BWmap entry in Table 2 can be calculated from the StartTime and GrantSize, and the original standard XG-PON BWmap entry has the StartTime and GrantSize fields. During the standard conversion process, the field contents in the original standard entry can be calculated to obtain the corresponding field contents in the target standard entry.

[0104] In an exemplary embodiment, the target standard GPON BWmap entry in Table 2 does not have message content corresponding to the FWI field in the original standard entry, and the field can be added to the GPON BWmap field or the forced wake-up indication (FWI) function can be directly cancelled.

[0105] Through the embodiments of the present application, the standard conversion from XG-PON BWmap entries to GPON BWmap entries can be achieved, and then the integrated networking of FTTH segment networks and FTTR segment networks of different standards can be realized.

[0106] In another exemplary embodiment, the downlink frame is a passive optical network encapsulation frame, and the master device checks the Port-ID (port identifier) ​​in the passive optical network encapsulation frame. If the Port-ID is a broadcast Port-ID, or the Port-ID is an identifier of a device downstream of the master device, the master device converts the XGEM frame of the XG-PON standard into a GEM frame of the GPON standard, and forwards the converted GEM frame to its downstream FTTR slave device. It should be pointed out that the GPON Port-ID has a smaller value range than the XG-PON Port-ID, and the OLT must comply with the GPON value range when configuring the GEM Port for the slave gateway.

[0107] Figure 5This is a schematic diagram of the structure of the XGEM frame of the XG-PON standard. Figure 5 As shown, the message header of the XGEM frame includes the following fields:

[0108] Payload Length Indicator (PLI), Key Index, XGEM Port-ID, Options, Loss of Frame (LF), Header Error Control (HEC).

[0109] Figure 6 This is a schematic diagram of the structure of the GEM frame of the GPON standard, such as Figure 6 As shown, the message header of the GEM frame includes the following fields:

[0110] Payload Length Indication (PLI), Port Identifier (Port-ID), Payload Type Indication (Packet Type Identifier, referred to as PTI), Header Error Control (Header Error Control, referred to as HEC).

[0111] In an exemplary embodiment, the fields and related content correspondence between the XGEM frame and the GEM frame may be shown in Table 3 below. This embodiment is only described by taking the conversion relationship from the XGEM frame of the XG-PON standard to the GEM frame of the GPON standard as an example, and the technicians may also implement the conversion of encapsulated messages of other different standards according to the standard conversion rules and the message structures of different standards, and this application does not limit this.

[0112] Table 3:

[0113]

[0114]

[0115] In an exemplary embodiment, the LF field of the XGEM frame in Table 3 can be converted to the PTI field of the GEM frame. It should be noted that the Key_Index of the XGEM frame is used to indicate the encryption state and the key index used of the XGEM frame, and is converted into the Encrypt_Port-ID PLOAM message in the GPON standard for switching the GEM frame encryption state, and the Key_Switching_Time PLOAM message is used for switching the key index.

[0116] Through the embodiments of the present application, the format conversion from XG-PON downstream XGEM frame to GPON downstream GEM frame can be achieved, and then the integrated networking of FTTH segment networks and FTTR segment networks of different formats can be realized.

[0117] In this embodiment, since the XG-PON standard rate is higher than the GPON standard rate, the master device needs to cache the downstream frames when performing downstream equal-delay forwarding. In order to reduce the cache quantity and prevent cache overflow, the FTTH optical line terminal performs certain balancing and interleaving on the downstream traffic, so that the services to the downstream devices of each master device are distributed as evenly as possible.

[0118] In this embodiment, the master device performs format conversion and equal-delay forwarding on the services in the upstream direction. The master device receives an upstream burst, converts the GPON-standard upstream burst into an XG-PON-standard upstream burst and forwards it to the FTTH optical line terminal (OLT).

[0119] In an exemplary embodiment, the correspondence between the GPON standard upstream PLOAM message and the XG-PON standard upstream PLOAM message is shown in Table 4.

[0120] Table 4:

[0121]

[0122] Through the embodiments of the present application, the standard conversion from the GPON standard uplink PLOAM message to the XG-PON standard uplink PLOAM message can be realized, and then the integrated networking of FTTH segment networks and FTTR segment networks of different standards can be realized.

[0123] In this embodiment, when the master device receives an uplink burst, it needs to consume a certain amount of preamble to lock the clock, search for delimiters, and obtain the uplink burst content to identify which FTTR slave device the uplink burst message comes from. When the master device forwards the uplink burst to the OLT, it needs to restore the uplink burst preamble and delimiter, so the master device needs to cache the uplink burst locally.

[0124] In this embodiment, the cache time of the uplink forwarding needs to be consistent for all slave devices and all uplink bursts, so that the uplink forwarding delay remains consistent. Further, in order to achieve uplink and downlink symmetry, it is possible to consider introducing the same cache time in the downlink forwarding of the master device, and of course, the delay caused by the identification, filtering and format conversion in the downlink direction must be comprehensively considered. The master device can perform a certain analysis on the uplink burst to obtain the identity information of the slave device, or obtain the identity information of the slave device based on the correspondence between the downlink management information and the uplink burst, thereby establishing a topological relationship between the master device and the FTTR slave device.

[0125] In implementation mode three, the FTTH and FTTR sections adopt different standards, and the rate of the FTTH section is not higher than the rate of the FTTR section.

[0126] In an exemplary embodiment, the FTTH segment adopts the symmetrical GPON standard, with upstream and downstream rates of 2.5G / 2.5G respectively, and the FTTR segment adopts the XG-PON standard, with upstream and downstream rates of 2.5G / 10G respectively. In addition to the listed standards, other standards are not repeated.

[0127] In this embodiment, in the downstream direction, the master device identifies, filters, and converts the downstream management information and services, and then forwards them with equal delay. The master device filters out the management information and services of the downstream FTTR slave device belonging to the master device, or the broadcast management information and services, and forwards these management information and services to the downstream FTTR slave device, and does not forward others. Before forwarding, the management information and services are converted from the GPON standard to the XG-PON standard.

[0128] In an exemplary embodiment, the downlink frame is a PLOAM message. The master device checks the SFU-ID / ONU-ID in the PLOAM message. If the SFU-ID / ONU-ID is a broadcast SFU-ID / ONU-ID, or the SFU-ID / ONU-ID belongs to a slave device downstream of the master device, the master device forwards the PLOAM message. The downlink frame is converted from a PLOAM message of the GPON standard to a PLOAM message of the XG-PON standard. The conversion relationship can refer to the conversion from right to left in Table 1.

[0129] In an exemplary embodiment, the downlink frame is a BWmap entry, and the master device checks the Alloc-ID in the BWmap entry. If the Alloc-ID is a broadcast Alloc-ID, or the Alloc-ID is a slave device downstream of the master device, the master device forwards the BWmap entry. The master device can save these BWmap entries locally for receiving upstream bursts sent by the slave device. The downlink frame is converted from the BWmap entry of the GPON standard to the BWmap entry of the XG-PON standard. The conversion relationship can refer to the conversion from right to left in Table 2.

[0130] In an exemplary embodiment, the downstream frame is a GEM frame, and the master device checks the Port-ID in the GEM frame. If the Port-ID is a broadcast Port-ID, or the Port-ID is a slave device downstream of the master device, the master device forwards the GEM frame, and the downstream frame is converted from the GEM frame of the GPON standard to the GEM frame of the XG-PON standard (i.e., the XGEM frame). The conversion relationship can refer to the conversion from right to left in Table 3. In addition, since the rate of the symmetrical GPON standard is slower than the rate of the XG-PON standard, a certain amount of buffering is required for downstream forwarding, and the buffering time needs to keep the downstream forwarding delay consistent.

[0131] In this embodiment, in the uplink direction, the master device performs system conversion and equal-delay forwarding on the uplink service. The master device receives the uplink burst, converts the uplink burst of the XG-PON system into the uplink burst of the GPON system and forwards it to the OLT. The conversion relationship can refer to the conversion from right to left of the uplink PLOAM message in Table 4.

[0132] In this embodiment, when the master device receives an uplink burst, it needs to consume a certain amount of preamble lock clock, search for delimitation, and obtain the uplink burst content. When the master device forwards the uplink burst content to the OLT, it needs to restore the uplink burst preamble and delimitation. Therefore, the master device needs to cache the uplink burst locally for a certain period of time. In addition, since the XG-PON standard rate of the FTTR section is relatively high and the GPON rate of the FTTH section is relatively low, the uplink burst also needs to be cached before forwarding. This cache time needs to be consistent for all slave devices and all uplink bursts.

[0133] In some embodiments, in order to ensure uplink and downlink symmetry, the delay caused by downlink conversion and caching can be comprehensively considered, and a certain cache time can also be introduced in the downlink forwarding of the master device to make the uplink forwarding delay and the downlink forwarding delay the same.

[0134] In some embodiments, the master device may also perform certain analysis on the uplink burst to obtain the identity information of the slave device, or obtain the identity information of the FTTR slave device based on the correspondence between the downlink management information and the uplink burst, thereby establishing a subordinate topology relationship between the master device and the FTTR slave device.

[0135] Through the embodiments of the present application, when the FTTR segment and the FTTH segment adopt different standards, the FTTR network and the FTTH network can be integrated into a whole, and low-latency service transmission can be achieved through equal-delay forwarding of upstream and downstream frames between the FTTR segment and the FTTH segment, thereby logically forming a passive optical network in which FTTH and FTTR work together.

[0136] In an exemplary embodiment, in the downstream direction, taking the Profile message in the downstream PLOAM message of the XG-PON standard as an example, the conversion process and conversion rules of converting the Profile message into the Upstream_Overhead message and Extended_Burst_Length message in the downstream PLOAM message of the GPON standard are described in detail.

[0137] In this embodiment, the composition structure of the Profile message is shown in Table 5, the composition structure of the Upstream_Overhead message is shown in Table 6, and the composition structure of the Extended_Burst_Length message is shown in Table 7. The corresponding relationship of the format conversion from the Profile message to the Upstream_Overhead message and the Extended_Burst_Length message is shown in Table 8.

[0138] Table 5:

[0139]

[0140]

[0141] Table 6:

[0142]

[0143]

[0144] Table 7:

[0145]

[0146] Table 8:

[0147]

[0148]

[0149] In this embodiment, according to the conversion relationship in Table 8, the Profile message in the XG-PON standard downstream PLOAM message can be converted to obtain the Upstream_Overhead message and Extended_Burst_Length message in the GPON standard downstream PLOAM message. However, the present application is not limited to this, and other downstream PLOAM messages, GEM frames or BWmap entries can also be converted according to their respective message contents and standard conversion rules.

[0150] In an exemplary embodiment, in the uplink direction, taking the Serial_Number_ONU (ONU serial number) message in the uplink PLOAM message as an example, the conversion process and conversion rules from the GPON standard to the XG-PON standard are described in detail.

[0151] In this embodiment, the message content of the Serial_Number_ONU message of the XG-PON standard is shown in Table 9, and the message content of the Serial_Number_ONU message of the GPON standard is shown in Table 10. The corresponding relationship of the standard conversion from the Serial_Number_ONU message of the GPON standard to the Serial_Number_ONU message of the XG-PON standard is shown in Table 11.

[0152] Table 9:

[0153]

[0154] Table 10:

[0155]

[0156] Table 11:

[0157] Serial_Number_ONU message content of XG-PON standard GPON standard Serial_Number_ONU message content 0x03FF 255 0x01 0x01 0x00 - Vendor_ID 3-6 bytes VSSN 7-10 bytes Random_delay 11 bytes of RRRRRRRR and 12 bytes of RRRR - 12-byte AGTT

[0158] In this embodiment, according to the conversion relationship in Table 9, the Serial_Number_ONU message in the GPON standard upstream PLOAM message can be converted to obtain the Serial_Number_ONU message in the XG-PON standard upstream PLOAM message. However, the present application is not limited thereto, and other upstream PLOAM messages can also be converted according to their respective message contents and standard conversion rules.

[0159] Through the embodiments of the present application, it is possible to implement the conversion of uplink and downlink frames of different standards, realize low-latency service forwarding across FTTH and FTTR networks, and improve the overall network performance. When performing FTTH and FTTR integrated networking, the restrictions of the network standards can be ignored, and the networking method is more flexible.

[0160] In some embodiments of the present application, in order to achieve equal-delay forwarding, it is necessary to cache the uplink and downlink frames for a certain period of time. The setting of the cache time needs to comprehensively consider the impact of message identification, format conversion, and the rates of different formats. In the uplink direction, when receiving an uplink burst, the master device needs to consume a certain amount of leading lock clock, search for delimiters, and obtain the uplink burst content to identify the FTTR slave device to which the uplink frame belongs. When the master device forwards the uplink burst to the OLT, it needs to restore the uplink burst leading and delimiters, so the master device needs to cache the uplink burst locally for a certain period of time.

[0161] Figure 7 This is a schematic diagram of the structure of the GPON standard uplink burst message, such as Figure 7 As shown, according to ITU-T G.984.3, the uplink burst message of GPON standard consists of the following structure:

[0162] Burst mode overhead, Burst header, G-PON Transmission Convergence (GTC) overhead, GTC payload.

[0163] The burst mode overhead includes: guard time, preamble, and delimiter.

[0164] The burst frame header includes: Bit Interleaved Parity (BIP), Optical Network Unit Identification (ONU-ID), and Indication (Ind).

[0165] GTC overhead includes: Physical Layer Operations, Administration, and Maintenance upstream (PLOAMu) and Dynamic Bandwidth Reporting upstream (DBRu).

[0166] Figure 8 This is a schematic diagram of the structure of the XG-PON standard uplink burst message, such as Figure 8 As shown, according to ITU-T G.987.3, the uplink burst message (such as physical layer burst) of the XG-PON standard consists of the following structure:

[0167] The upstream physical synchronization block (Physical Synchronization Block upstream, referred to as PSBu) and the physical layer burst payload, wherein the physical layer burst payload is represented by the upstream XG-PON transmission convergence layer (XG-PON TransmissionConvergence, referred to as XGTC).

[0168] PSBu includes: preamble and delimiter.

[0169] XGTC includes: XGTC header, DBRu, XGTC payload, and XGTC trailer.

[0170] The XGTC header includes: ONU-ID, Ind, HEC, and PLOAMu.

[0171] The XGTC tail includes the BIP.

[0172] In this embodiment, the conversion relationship between the XG-PON upstream burst and the GPON upstream burst is shown in Table 12. In addition to the conversion of these fields, other fields such as preamble, delimiter, BIP, HEC and other fields are generated according to the methods specified in the XG-PON and GPON standards. If the upstream burst also involves FEC verification, it is also generated according to the methods specified in the XG-PON and GPON standards.

[0173] Table 12:

[0174]

[0175]

[0176] In an exemplary embodiment, in the uplink frame forwarding process of the above-mentioned embodiment 2 (the FTTH segment adopts the XG-PON standard and the FTTR segment adopts the GPON standard), the master device recovers the locked clock by consuming the preamble of the GPON uplink burst, and then searches for the delimiter, and performs standard conversion from the BIP domain (see the above table) and then forwards the converted message content to the FTTH optical line terminal. Before forwarding, the preamble and delimiter in the XG-PON standard need to be sent first.

[0177] In another exemplary embodiment, during the uplink frame forwarding process of the above-mentioned implementation mode three (the FTTH segment adopts the symmetrical GPON standard and the FTTR segment adopts the XG-PON standard), the master device recovers the locked clock by consuming the preamble code (Preamble) of the XG-PON uplink burst, and then searches for the delimiter (Delimiter), and performs standard conversion starting from the ONU-ID domain (see the above table) and then forwards the converted message content to the FTTH optical line terminal. Before forwarding, the preamble code (Preamble) and delimiter (Delimiter) in the GPON standard need to be sent first.

[0178] In this embodiment, in addition to the conversion time consumed for converting the format of the uplink frame, it is also necessary to consider the preamble consumption time of the uplink frame and the time spent on recovering the preamble, the time for searching the delimiter and the time for recovering the delimiter, so that the uplink forwarding time of all uplink frames from the device is consistent. The source of the uplink frame can be identified after consuming the preamble code to lock the clock, search the delimiter and obtain the uplink burst content, so this time can also be called the time consumed for identifying the uplink frame and regenerating the burst overhead.

[0179] Through the embodiments of the present application, the uplink and downlink frames can be cached respectively according to the uplink and downlink processing time, the rate of the FTTH segment and the rate of the FTTR segment, so as to realize equal-delay forwarding of the uplink and downlink frames, thereby realizing the unified management of different FTTR slave devices by the FTTH optical line terminal, and logically forming a passive optical network in which FTTH and FTTR cooperate with each other.

[0180] The embodiment of the present application provides a passive optical network architecture that realizes the integration of FTTH network and FTTR network, unifying the FTTH network and FTTR network into one network to realize unified resource scheduling, management and operation of FTTH and FTTR.

[0181] In an embodiment of the present application, the master device can establish a communication channel for the FTTR slave device and the FTTH OLT, and the master device can identify, store, filter, convert and forward the upstream and downstream services. During the conversion process, the master device can convert the functions in the original standard into the functions in the target standard. If the target standard does not support the functions in the original standard, the master device may not convert these functions, or add corresponding functions in the target standard, and the master device may perform the corresponding function conversion.

[0182] In the embodiment of the present application, the FTTH and FTTR segments are forwarded to each other through the master device. If the rates of the two segments are different, the master device needs to cache and then forward; if the standards of the two segments are different, they need to be cached and converted before forwarding; in addition, the master device needs to consume a certain amount of leading and delimiting to identify the uplink burst during the forwarding process of the uplink burst. The master device needs to forward the uplink burst after restoring the leading and delimiting of the uplink burst, so it also needs to cache. In order not to affect the ranging results of each slave device, after considering the above factors and other necessary factors, the uplink and downlink forwarding time of each slave device in the forwarding process in the master device should be kept consistent and stable, so that the uplink and downlink transmission time is consistent.

[0183] In the embodiment of the present application, the master device establishes equal-latency forwarding channels for the FTTH OLT and the FTTR slave device, which can realize the logical integrated networking of FTTH and FTTR. The slave device and the master device logically belong to the ONU under the OLT. FTTR is an extension of FTTH. The FTTH OLT can uniformly schedule resources for the FTTR slave device, which can realize low-latency service transmission, and the FTTH OLT can directly manage the FTTR slave device. The FTTR master device can independently build a home internal network with the FTTR slave device. By modifying or replacing the FTTH home gateway device as the master device and deploying the indoor optical distribution network of the FTTR, the slave device can be directly accessed, and then the configuration and service of the SFU can be opened on the FTTH management platform. According to business needs, the FTTR slave device can also establish an equal-latency forwarding channel, so that the downstream device of the FTTR slave device also becomes an extension of the FTTR network and the FTTH network, and logically becomes a network with the FTTH network and the FTTR network.

[0184] In the embodiment of the present application, not only can slave devices of the same standard be directly connected to the master device, but slave devices of different standards can also be directly and conveniently connected to the master device, which improves the flexibility of networking.

[0185] According to another embodiment of the present application, a data transmission method is also provided, which is applied to a passive optical network architecture, wherein the architecture includes: an FTTH optical line terminal, a master device, and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices.

[0186] Fig. 9 is a flowchart of a data transmission method according to an embodiment of the present application, such as Fig. 9 As shown, the process includes the following steps:

[0187] Step S1, forwarding the downlink frame isochronous delay from the FTTH optical line terminal to the FTTR slave device through the forwarding channel between the FTTH optical line terminal and the FTTR slave device;

[0188] Step S2, forwarding the uplink frame isochronous delay from the FTTR slave device to the FTTH optical line terminal through the forwarding channel, wherein the forwarding channel is established by the master device.

[0189] Through the embodiments of the present application, equal-delay forwarding of upstream and downstream frames can be achieved between FTTR and FTTH, and integrated networking of FTTR and FTTH can be realized, logically forming a passive optical network in which FTTH and FTTR cooperate with each other.

[0190] According to another embodiment of the present application, a master device is also provided, which is applied to a passive optical network architecture, wherein the architecture includes: an FTTH optical line terminal, a master device, and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein the master device is used to establish a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and to perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

[0191] Fig.10 is a schematic diagram of the structure of a passive optical network architecture according to an embodiment of the present application, such as Fig.10 As shown, the main device includes a forwarding channel and an FTTH ONU (Optical Network Unit).

[0192] In this embodiment, the FTTH ONU and the forwarding channel in the master device are respectively connected to the FTTH OLT to independently implement their respective functions.

[0193] In this embodiment, the forwarding channel is used to connect the FTTR optical network unit and the FTTH optical line terminal, and is responsible for the identification, filtering, format conversion and equal-delay forwarding of upstream and downstream frames between the FTTR ONU and the FTTH OLT.

[0194] Fig.11 is a schematic diagram of a passive optical network architecture according to another embodiment of the present application, such as Fig.11 As shown, the main device includes a forwarding channel and an FTTH ONU (Optical Network Unit).

[0195] In this embodiment, the FTTH ONU in the master device is connected to the FTTH OLT through a forwarding channel, and the FTTR slave device is also connected to the FTTH OLT through a forwarding channel.

[0196] Fig.12 is a schematic diagram of the structure of a passive optical network architecture according to another embodiment of the present application, such as Fig.12 As shown, the main device includes a forwarding channel and an FTTH ONU (Optical Network Unit).

[0197] In this embodiment, the forwarding channel and the FTTH ONU are integrated, and the function of the forwarding channel can be implemented by the FTTH ONU.

[0198] Through the embodiments of the present application, the integrated networking of FTTH and FTTR can be realized, and the FTTH ONU and FTTR ONU are uniformly configured with resources and controlled by the FTTH OLT, so as to logically form a passive optical network in which FTTH and FTTR cooperate with each other.

[0199] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail herein.

[0200] Obviously, those skilled in the art should understand that the above modules or steps of the present application can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order from that herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present application is not limited to any specific combination of hardware and software.

[0201] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.

Claims

1. A passive optical network architecture, characterized in that: The architecture includes: an FTTH optical line terminal, a master device and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein: The master device is used to establish a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and to perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

2. The architecture according to claim 1, characterized in that The master device is used to identify the target device of the downlink frame, filter the downlink frame according to the target device, and delay forwarding the downstream downlink frame or broadcast downlink frame belonging to the downstream device of the master device to the downstream device of the master device, wherein the downstream device of the master device is an FTTR slave device directly connected to the master device.

3. The architecture according to claim 2, characterized in that: The downlink frame includes at least one of the following: Physical layer operation management and maintenance PLOAM messages; Bandwidth mapping BWmap entry; Passive optical network encapsulation frame.

4. The architecture according to claim 3, characterized in that The master device is used for identifying the target device of the PLOAM message according to the slave device identifier SFU ID or the optical network unit identifier ONU ID in the PLOAM message when the downlink frame is a PLOAM message; and / or, The master device is configured to, when the downlink frame is a BWmap entry, identify a target device of the BWmap entry according to an allocation identifier Alloc-ID in the BWmap entry; and / or, The master device is used to identify the target device of the passive optical network encapsulation frame according to the port identifier Port ID in the passive optical network encapsulation frame when the downlink frame is a passive optical network encapsulation frame.

5. The architecture according to claim 1, characterized in that: The master device is used to convert an original standard message into a target standard message when the original standard is different from the target standard, wherein the original standard and the target standard are respectively an optical network specification, and when the original standard message is a downlink frame received by the master device from the FTTH optical line terminal, the target standard message is a downlink frame sent by the master device to the FTTR slave device, and when the original standard message is an uplink frame received by the master device from the FTTR slave device, the target standard message is an uplink frame sent by the master device to the FTTH optical line terminal.

6. The architecture according to claim 5, characterized in that The master device is used to convert multiple fields in the original standard message into multiple fields in the target standard message according to a preset standard conversion rule; The system conversion rule includes at least one of the following: In the case where the first field and the second field are the same, converting the field value of the first field into the field value of the second field, wherein the first field is any field in the original standard message, and the second field is any field in the target standard message; When there is no field identical to the first field in the target standard message, adding the first field as a new field to the target standard message; If there is no field identical to the second field in the original standard message, delete the second field from the target standard message; When the length of the target standard message is smaller than the length of the original standard message, some fields in the original standard message are deleted.

7. The architecture according to claim 5, characterized in that: The FTTH segment standard includes at least one of the following: GPON standard, symmetric GPON standard, XG-PON standard, XGS-PON standard, and 50G-PON standard, wherein the FTTH segment standard is an optical network specification used between the FTTH optical line terminal and the main device; The FTTR segment standard includes at least one of the following: GPON standard, symmetric GPON standard, XG-PON standard, XGS-PON standard, G.fin standard, CCSA FTTR standard, 50G-PON standard, wherein the FTTR segment standard is an optical network specification used between the master device and the FTTR slave device.

8. The architecture according to claim 7, characterized in that The master device is further used to convert the downlink frame directly from the FTTH segment standard to the FTTR segment standard, or to convert the downlink frame to an intermediate standard, and then convert from the intermediate standard to the FTTR segment standard, wherein the intermediate standard is a network standard other than an optical network standard; The master device is further configured to convert the uplink frame directly from the FTTR segment format to the FTTH segment format, or to convert the uplink frame to the intermediate format and then convert from the intermediate format to the FTTH segment format.

9. The architecture according to claim 1, characterized in that: The master device is used to cache the downlink frame from the FTTH optical line terminal for a first time and then forward it to the FTTR slave device, so that the downlink forwarding delay consumed by the master device each time forwarding the downlink frame remains consistent, and cache the uplink frame from the FTTR slave device for a second time and then forward it to the FTTH optical line terminal, so that the uplink forwarding delay consumed by the master device each time forwarding the uplink frame remains consistent.

10. The architecture according to claim 9, characterized in that: The master device is used to determine the first time and the second time according to the downlink processing time and the uplink processing time when the original standard and the target standard are the same, wherein the original standard and the target standard are respectively an optical network specification; The master device is configured to determine the first time and the second time according to a rate of the original standard, a rate of the target standard, the downlink processing time, and the uplink processing time when the original standard is different from the target standard.

11. The architecture according to claim 10, characterized in that The downlink processing time includes at least one of the following: The identification time consumed for identifying the downlink frame; The filtering time consumed for filtering the downlink frame; The conversion time consumed for converting the format of the downlink frame; The uplink processing time includes at least one of the following: The identification time consumed for identifying the uplink frame; The conversion time consumed for converting the format of the uplink frame; The time consumed for regenerating the burst overhead of the uplink frame.

12. The architecture according to claim 1, characterized in that The architecture further includes: a downstream device from the device, each of the FTTR slave devices is connected to at least one downstream device from the slave device, wherein: The FTTR slave device is used to establish a forwarding channel between the master device and the downstream device of the slave device, and forward the downlink frame and other delays from the master device to the downstream device of the slave device through the forwarding channel, and forward the uplink frame and other delays from the downstream device of the slave device to the master device through the forwarding channel.

13. A data transmission method, characterized in that: Applied to a passive optical network architecture, the architecture includes: an FTTH optical line terminal, a master device and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, and each of the master devices is connected to at least one of the FTTR slave devices, wherein the method includes: The downstream frames and delays from the FTTH optical line terminal are forwarded to the FTTR slave device through a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and the upstream frames and delays from the FTTR slave device are forwarded to the FTTH optical line terminal through the forwarding channel, wherein the forwarding channel is established by the master device.

14. A master device, characterized in that: Applied to a passive optical network architecture, the architecture includes: an FTTH optical line terminal, a master device, and an FTTR slave device, each of the FTTH optical line terminals is connected to at least one of the master devices, each of the master devices is connected to at least one of the FTTR slave devices, wherein: The master device is used to establish a forwarding channel between the FTTH optical line terminal and the FTTR slave device, and to perform equal-delay forwarding of uplink and downlink frames between the FTTH optical line terminal and the FTTR slave device through the forwarding channel.

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