RU2809182C1 - Service data transmission method, corresponding device and digital processing chip - Google Patents

Abstract

FIELD: optical signal transmission.

SUBSTANCE: invention is related to transmission of service data. The first device encapsulates the channel frame in a transmission frame, in which the channel frame is used to carry service data, and sends the transmission frame to the second device. The channel frame transmission method is a method without decapsulation between an optical transport network and an access network.

EFFECT: reduction of delay in transmission of service data.

24 cl, 13 dwg

Description

TECHNICAL FIELD

[0001] This application relates to the field of optical signal transmission and, in particular, to a method for transmitting service data corresponding to a device and a digital processing chip.

BACKGROUND OF THE ART

[0002] As shown in FIG. 1, as a broadband optical access technology, passive optical network (PON) 101 is characterized by a point-to-multipoint physical topology structure. The PON 101 includes an optical line terminal (OLT) 102, an optical distribution network (ODN) 103, and a plurality of optical network units (ONUs) 104. PON must be used in collaboration with an appropriate transport mechanism to complete end-to-end service transmission. Optical transport network (OTN) 105 is an ultra-reliable and interoperable high-speed optical network, includes many OTN devices and can be used as a transport network interoperating with PON 101.

[0003] PON 101 and OTN 105 are independent of each other. To implement the relationship between PON 101 and OTN 105, a switching device 106 is required. In particular, the switching device 106 may be a switch or a router.

SUMMARY OF THE INVENTION

[0004] Embodiments of this application provide a method for transmitting overhead data, a corresponding device, and a digital processing chip for reducing overhead latency and network costs.

[0005] According to a first aspect, an embodiment of the present invention provides a method for transmitting service data. In the process of transmitting overhead data in the upstream direction, the first device is an ONU, and the second device is a convergence device. In the downstream transmission process, the first device is a convergence device and the second device is an ONU.

[0006] The method shown in this embodiment of the present invention includes: firstly, the first device encapsulates a channel frame in a transmission frame, where the channel frame is used to carry overhead data, wherein the channel frame transmission method is a method without decapsulation between optical transport network and access network, and the transmission frame includes indication information used to indicate the channel frame; and then the first device sends the transmission frame to the second device.

[0007] In this implementation, a channel frame is transmitted between the optical transport network and the access network without decapsulation. This effectively reduces the latency of overhead transmission between two networks. In addition, since the channel frame does not need to be sent between the optical transport network and the access network using a switching device, the network construction cost is effectively reduced.

[0008] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, before the first device encapsulates the channel frame in a transmission frame, the first device processes the channel frame to generate an intermediate frame, where the number of bytes corresponding to the intermediate frame is less than or equal to the first number of bytes, and the first number of bytes is the number of bytes corresponding to the payload area of the XGEM frame of a 10-gigabit passive optical network encapsulation method.

[0009] In this implementation, when the number of bytes corresponding to the channel frame does not correspond to the number of bytes corresponding to the XGEM frame, the first device may convert the channel frame into an intermediate frame. In addition, the number of bytes corresponding to an intermediate frame is less than or equal to the number of bytes corresponding to an XGEM frame, thereby increasing the likelihood of successful encapsulation of an intermediate frame in the payload region of the XGEM frame and preventing packet loss in the link frame. This effectively reduces the latency of channel frame encapsulation in the payload region of the XGEM frame.

[0010] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, that the first device processes the channel frame to generate an intermediate frame includes: if the second number of bytes is greater than the first number of bytes, the first device divides the channel frame to form a plurality of intermediate frames, where the second number of bytes is the number of bytes corresponding to the channel frame.

[0011] In this implementation, when the second number of bytes is greater than the first number of bytes, the first device may encapsulate an intermediate frame in the payload region of the XGEM frame by dividing the channel frame to form a plurality of intermediate frames. This increases the likelihood of successful encapsulation of a link frame in the payload region of the XGEM frame and prevents packet loss in the link frame.

[0012] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, the first device dividing a channel frame to form a plurality of intermediate frames includes: the first device receiving a division parameter, where the division parameter is a quotient between the second number of bytes used as the dividend and the first number of bytes used as the divisor; and the first device evenly divides the channel frame based on the division parameter to generate intermediate frames, where the number of intermediate frames is equal to the division parameter.

[0013] In this implementation, the channel frame is divided by receiving a division parameter. This effectively ensures that the number of bytes corresponding to the intermediate frame obtained after splitting can be less than or equal to the first number of bytes corresponding to the XGEM frame, increases the likelihood of successful encapsulation of a link frame in the payload region of the XGEM frame, and avoids packet loss in the link frame.

[0014] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, that the first device processes the channel frame to generate an intermediate frame includes: if the second number of bytes is less than or equal to the first number of bytes, the first device combines a plurality of channel frames to form an intermediate frame, where the second number of bytes is the number of bytes corresponding to the channel frame.

[0015] In this implementation, when the second number of bytes is less than or equal to the first number of bytes, the first device may combine multiple channel frames to form an intermediate frame such that the number of bytes corresponding to the received intermediate frame is less than or equal to the first number of bytes corresponding to the frame XGEM. This effectively increases the number of channel frames encapsulated in the payload area of the XGEM frame and improves the efficiency of the payload area of the XGEM frame.

[0016] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is a positive integer greater than 1.

[0017] In this implementation, upon determining that the quotient between the first number of bytes and the second number of bytes used as a divisor is greater than 1, the first device may combine the plurality of channel frames to form an intermediate frame. This effectively improves the bandwidth utilization of the payload region of the XGEM frame.

[0018] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, the first device encapsulates a channel frame in a transmission frame includes: the first device encapsulates an intermediate frame in a payload region of the XGEM frame; and the first device encapsulates the XGEM frame in a transmission frame, where the transmission frame is a 10 gigabit passive optical network transmission convergence XGTC frame.

[0019] In this implementation, the number of bytes corresponding to the intermediate frame received by the first device corresponds to the first number of bytes corresponding to the XGEM frame, so that the first device can directly encapsulate the intermediate frame in the payload region of the XGEM frame. This effectively increases the likelihood of successfully encapsulating an intermediate frame in the payload region of an XGEM frame and avoids packet loss.

[0020] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, the first intermediate frame is used to carry the first overhead data, the second intermediate frame is used to carry the second overhead data, and that the first device encapsulates the channel frame in transmission frame, includes: a first device encapsulates a first service slice and a second service slice in the payload domain of an interleaved XGEM frame, where the XGEM frame service information carries indication information, the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, and the ratio between the number of bytes included in the first overhead slice and the number of bytes included in the second overhead slice is equal to the throughput ratio between the first overhead data and the second overhead data; and the first device encapsulates the XGEM frame in a transmission frame, where the transmission frame is an XGTC frame.

[0021] In this implementation, the first device encapsulates in an interleaved XGEM frame a first intermediate frame and a second intermediate frame that carry different overhead data. Therefore, transmission delay and jitter in the transmission of overhead data can be effectively reduced, the utilization of the bandwidth allocated to the first device is effectively improved, and the complexity of dynamic bandwidth allocation (DBA) in the process of transmitting overhead data can be effectively reduced.

[0022] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, that the first device encapsulates a channel frame in a transmission frame includes: if the second number of bytes is less than or equal to the first number of bytes, the first device encapsulates a channel frame in a payload area of the XGEM frame, where the second number of bytes is a number of bytes corresponding to the channel frame, and the first number of bytes is a number of bytes corresponding to a payload area of the XGEM frame; and the first device encapsulates the XGEM frame in a transmission frame, where the transmission frame is an XGTC frame. In this implementation, the first device may directly encapsulate the channel frame in the payload region of the XGEM frame. This effectively simplifies the process of matching the channel frame and the XGEM frame, thereby reducing transmission latency.

[0023] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is 1.

[0024] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, if the first device is an optical network unit ONU, before the first device encapsulates a channel frame in a transmission frame, the method further includes: first the device receives service data; and the first device encapsulates the overhead data in a channel frame.

[0025] Based on the first aspect of the embodiments of the present invention, in an optional implementation of the first aspect of the embodiments of the present invention, if the first device is a convergence device, and the convergence device is configured to connect an optical transport network and an access network before the first device encapsulates a channel frame in a transmission frame, the method further includes: the first device receiving a channel frame from an optical transport network.

[0026] According to a second aspect, an embodiment of the present invention provides a method for transmitting service data. The method includes: a second device receiving a transmission frame from the first device, where the transmission frame includes indication information used to indicate a channel frame; and the second device receives a channel frame carried in a transmission frame, where the channel frame is used to carry overhead data, and a method for transmitting the channel frame is a method without decapsulation between an optical transport network and an access network. The beneficial effects shown in this aspect are related to the effects shown in the first aspect. The details are not repeated.

[0027] Based on the second aspect of the embodiments of the present invention, in an optional implementation of the second aspect of the embodiments of the present invention, the second device receives a channel frame carried in a transmission frame includes: the second device receives an intermediate frame carried in a transmission frame, where a number of bytes corresponding to an intermediate frame is less than or equal to the first number of bytes, and the first number of bytes is a number of bytes corresponding to a payload area of the XGEM frame; and the second device processes the intermediate frame to obtain a channel frame.

[0028] Based on the second aspect of the embodiments of the present invention, in an optional implementation of the second aspect of the embodiments of the present invention, the second device receives an intermediate frame carried in a transmission frame includes: the second device receives an XGEM frame carried in a transmission frame, where the transmission frame is an XGTC frame, and the overhead information of the XGEM frame carries indication information; the second device receives the first service slice and the second service slice from the XGEM frame, where the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, the first intermediate frame is used to carry the first service data, the second intermediate frame is used to carry the second service data , and the ratio between the number of bytes included in the first service slice and the number of bytes included in the second service slice is equal to the ratio of the throughput between the first service data and the second service data; the second device receives a first intermediate frame based on the first service slice; and the second device obtains a second intermediate frame based on the second service slice.

[0029] According to a third aspect, an embodiment of the present invention provides a digital processing chip. The chip includes a processor and a memory, the memory and the processor are interconnected by a line, the memory stores instructions, and the processor is configured to execute a method for transmitting service data in accordance with any of the first aspect, the second aspect, or an implementation of the first aspect or the second aspect.

[0030] According to a fourth aspect, an embodiment of the present invention provides a first device including a processor, a memory, and an optical transceiver. The processor, memory and optical transceiver are interconnected by a line. The processor calls program code in memory to perform a processing function performed by the first device in accordance with any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect. The optical transceiver is configured to perform a send/receive function performed by the first device in accordance with any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect.

[0031] According to a fifth aspect, an embodiment of the present invention provides a second device including a processor, a memory, and an optical transceiver. The processor, memory and optical transceiver are interconnected by a line. The processor calls program code in memory to perform a processing function performed by the second device in accordance with any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect. The optical transceiver is configured to perform a send/receive function performed by the second device in accordance with any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect.

[0032] In accordance with a sixth aspect, an embodiment of the present invention provides a computer-readable storage medium including instructions. When the instructions are executed on a computer, the computer is capable of executing a method for communicating service data in any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect.

[0033] According to a seventh aspect, an embodiment of the present invention provides a computer program product including instructions. When the computer program product runs on a computer, the computer is capable of executing a service data communication method in any of the first aspect, the second aspect, or implementations of the first aspect or the second aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 is an exemplary network architecture diagram of an existing communication system;

[0035] FIG. 2 is an exemplary network architecture diagram of a communication system according to the present invention;

[0036] FIG. 3 is a step-by-step flowchart of an embodiment of a method for transmitting service data in accordance with the present invention;

[0037] FIG. 4 is an exemplary protocol stack diagram of a communication system according to the present invention;

[0038] FIG. 5 is an example diagram of a communication system protocol stack in accordance with an existing solution;

[0039] FIG. 6 is a step-by-step flowchart of another embodiment of a method for transmitting service data in accordance with the present invention;

[0040] FIG. 7 is an exemplary service data encapsulation diagram according to the present invention;

[0041] FIG. 8 is another exemplary service data encapsulation diagram according to the present invention;

[0042] FIG. 9 is a step-by-step flowchart of another embodiment of a method for transmitting service data in accordance with the present invention;

[0043] FIG. 10 is another exemplary service data encapsulation diagram according to the present invention;

[0044] FIG. 11 is an exemplary diagram of an XGTC frame structure according to the present invention;

[0045] FIG. 12 is a step-by-step flowchart of another embodiment of a method for transmitting service data in accordance with the present invention; And

[0046] FIG. 13 is an exemplary design diagram of a first device or a second device according to the present invention.

Description of Embodiments

[0047] Technical solutions in embodiments of the present invention are clearly described below with reference to the accompanying drawings.

[0048] To better understand the service data transmission method provided in this application, the following will be described with reference to FIG. 1, defect in the implementation of service data transmission in the existing communication system.

[0049] In the communication system shown in FIG. 1, PON 101 and OTN 105 belong to different types of networks, and therefore the two networks cannot be directly connected to realize end-to-end interconnection. For example, OTN 105 uses the OTN network type, and PON 101 uses the XG (10-gigabit-capable passive optical network, 10GPON) network type. Failure to realize end-to-end connection indicates that service data cannot be directly exchanged between OTN 105 and PON 101. This causes the service data transmission delay to increase.

[0050] The following describes a process for transmitting overhead data between communication networks that cannot implement end-to-end connectivity. The direction in which the overhead data is transmitted from the OTN 105 to the PON 101 is defined as a downstream transmission direction, and the direction in which the overhead data is transmitted from the PON 101 to the OTN 105 is defined as an upstream transmission direction.

[0051] For example, overhead data is transmitted in the uplink direction. A user-side device (such as a computer, telephone, or television) sends service data to the ONU 104. ONU 104 encapsulates the service data as a GPON encapsulation method (GEM) frame. The ONU 104 encapsulates the GEM frame in the uplink packet of the optical burst. The ONU 104 sends the uplink optical burst packet to the OLT 102.

[0052] To implement end-to-end communication, PON 101 and OTN 105 must exchange service data using switching device 106. Specifically, an example will be used for description in which OLT 102 is connected to switching device 106 using an Ethernet interface. When there are multiple OLTs 102, the switching device 106 must be separately connected to different OLTs using different Ethernet interfaces. That is, each Ethernet interface of switching device 106 corresponds to only one unique OLT 102.

[0053] Ethernet (Ethernet) is the local area network communication method and protocol currently most widely used. An Ethernet interface is a port that uses the Ethernet protocol and is used for data transfer. An Ethernet interface may be configured to receive or send a signal using the Ethernet protocol, such as an Ethernet frame.

[0054] When the OLT 102 receives an uplink optical burst packet from the ONU 104, the OLT 102 needs to complete transmission of the uplink optical burst packet. OLT 102 receives overhead data by analyzing the upstream packet of an optical burst. OLT 102 sends service data to switching device 106 using an Ethernet interface.

[0055] OTN device 107 receives an Ethernet frame from switching device 106 using an Ethernet interface. The OTN device 107 obtains the overhead by analyzing the Ethernet frame. The OTN device 107 sends service data to the network server. Alternatively, OTN device 107 sends service data to another OTN device in OTN 105. The network server may be the Internet, a public switched telephone network (PSTN), or the like.

[0056] It can be learned that since point-to-point communication is implemented between the PON 101 and the OTN 105 using the Ethernet interface, a relatively large number of transmission media are used, the cost is relatively high, and the transmission delay in the process of transmitting overhead data is high. In view of this, this application provides a service data transmission technology to effectively reduce the transmission delay in the service data transmission process when realizing an end-to-end connection between PON and OTN. In addition, in this application, there is no need to install a switching device between PON and OTN, which effectively reduces the cost of network construction.

[0057] The following first provides, with reference to FIG. 2 is an example of a description of the network architecture of a communication system to which the service data transmission method provided in this application is applied.

[0058] As shown in FIG. 2, the communication system provided in this embodiment includes a convergence device 201. The convergence device 201 has OLT and OTN device functions, which are shown in FIG. 1. Since the OTN device is a device located in the optical transport network and the OLT is a device located in the access network, it can be recognized that the convergence device is configured to connect PON 202 used as an access network and OTN 203 used as transport network.

[0059] The PON 202 shown in this embodiment includes an optical distribution network (ODN) 204. The ODN 204 is connected to a plurality of optical network units (ONUs) 205. The convergence device 201 shown in this embodiment has a PON interface. The convergence device 201 communicates with the ODN 204 based on a PON interface.

[0060] In this embodiment, for example, the network type of PON 202 is 10GPON. It should be noted that the specific type of PON 202 is not limited in this embodiment. For example, PON 202 may alternatively use a gigabit passive optical network (GPON). Alternatively, PON 202 may use the next higher speed network type, such as a 25G passive optical network (25GPON), a 50G passive optical network (50GPON), or a 100G passive optical network (100GPON). Different types of PON 202 networks may use different PON interfaces described above.

[0061] The convergence device 201 shown in this embodiment further has an optical transport network (OTN) interface. The convergence device 201 communicates with the OTN device 206 at the OTN 203 based on the OTN interface.

[0062] The following describes with reference to FIG. 3 and fig. 4, an embodiment of the service data transmission method provided in this application. Fig. 3 is a step-by-step flowchart of an embodiment of a method for transmitting service data in accordance with the present invention. Fig. 4 is an exemplary protocol stack diagram of a communication system according to the present invention. In this embodiment, an example in which the overhead is transmitted in the uplink direction is used for description.

[0063] Step 301: The ONU receives service data from the user-side device.

[0064] As shown in FIG. 4, ONU 401 receives upstream service data from a user-side device using a user network interface (UNI). In this embodiment, the type of upstream service data is not limited. For example, the service type may be a packet service, a time division multiplexing (TDM) service, or the like.

[0065] Step 302: The ONU encapsulates overhead data in a channel frame.

[0066] The ONU may preset a value for the number of bytes corresponding to a channel frame, such as 8 bytes, 16 bytes, 32 bytes, 64 bytes, 128 bytes, 192 bytes, 256 bytes, or 512 bytes.

[0067] Optionally, the ONU may reduce the number of bytes value corresponding to the channel frame to reduce latency in encapsulating overhead data in the channel frame. To simplify the process of negotiating the encapsulation of service data in a channel frame, the ONU may increase the value of the number of bytes corresponding to the channel frame.

[0068] The frame structure of a channel frame shown in this embodiment may include bytes or bits the number of which is an integer multiple. In particular, the channel frame includes an overhead area and a payload area. The service information area includes, but is not limited to, service frame header indication, trail trace identifier (TTI), X bit-interleaved parity (BIP-X), reverse error indication ( backward error indication (BEI), backward defect indication (BDI), status indication (Status), timestamp, sequence identifier, display overhead, tributary port number (TPN), or the like. The payload area is used to carry overhead data.

[0069] The ONU may predetermine the channel frame rate value. For example, the channel frame rate is 2 megabits per second (Mbps), 10 Mbps, 100 Mbps, 200 Mbps, 500 Mbps, 1 gigabits per second (Gbps), etc. The specific value of the channel frame rate is not limited in this embodiment, as long as the channel frame rate is greater than or equal to the overhead data rate.

[0070] As shown in FIG. 4, an ONU side channel layer 402 can be added to the ONU. The channel layer 402 on the ONU side is configured to: determine the number of bytes corresponding to the channel frame, and asynchronously encapsulate service data in the channel frame. The specific method of arranging the channel layer 402 on the ONU side in this embodiment is not limited. For example, a circuit board or the like configured to implement a link layer function on the ONU side may be located in the ONU.

[0071] Step 303: The ONU encapsulates the channel frame in an XGEM frame.

[0072] The number of bytes corresponding to a channel frame is fixed, and the ONU can set the frame rate for the channel frame to carry overhead data with different bandwidths. The frame rate for a 10 GPON encapsulation method (XGEM) frame is fixed, and the number of bytes corresponding to the payload area of the XGEM frame is variable. Step 303 shown in this embodiment is directed to encapsulating a channel frame in the payload region of the XGEM frame. In particular, the following two methods are shown:

[0073] Method 1:

[0074] When the ONU determines that the second number of bytes corresponding to the channel frame does not correspond to the first number of bytes corresponding to the payload area of the XGEM frame, the ONU may process the channel frame to generate an intermediate frame. The number of bytes corresponding to the generated intermediate frame is the same as the first number of bytes. That the second number of bytes corresponding to the channel frame does not correspond to the first number of bytes corresponding to the payload area of the XGEM frame may specifically indicate that the second number of bytes is greater than the first number of bytes or indicate that the second number of bytes is less than the first number of bytes. That the number of bytes corresponding to the intermediate frame corresponds to the first number of bytes may specifically indicate that the number of bytes corresponding to the intermediate frame is less than or equal to the first number of bytes.

[0075] The method for generating the intermediate frame in this embodiment is not limited. For example, a channel frame may be divided to form multiple intermediate frames. In another example, multiple channel frames may be combined to form an intermediate frame. When the ONU receives an intermediate frame, the ONU may synchronously encapsulate the intermediate frame in the payload area of the XGEM frame.

[0076] Method 2:

[0077] If the ONU determines that the second number of bytes corresponding to the channel frame is less than or equal to the first number of bytes corresponding to the payload area of the XGEM frame, the ONU may directly synchronously encapsulate the channel frame in the XGEM frame.

[0078] As shown in FIG. 4, the ONU side channel layer 402 is located at the XGEM layer 403. The XGEM layer 403 may perform the above process of encapsulating a channel frame within an XGEM frame.

[0079] Step 304: The ONU encapsulates the XGEM frame in a transmit frame.

[0080] The transmission frame shown in this embodiment may be a 10 gigabit passive optical network transmission convergence (XGPON transmission convergence, XGTC) frame. In particular, the ONU may encapsulate an XGEM frame in the payload region of an XGTC frame. The indication information is set in the overhead information of the XGEM frame shown in this embodiment. It can be recognized that the indication information is specifically used to indicate that the data carried in the payload area of the XGEM frame is a channel frame.

[0081] As shown in FIG. 4, XGEM level 403 is located at XGTC level 404. The XGTC layer 404 is configured to encapsulate an XGEM frame within an XGTC frame.

[0082] Step 305: The ONU sends a transmit frame to the convergence device.

[0083] In this embodiment, the ONU may send a transmission frame to the convergence device using the PON interface.

[0084] As shown in FIG. 4, the XGTC layer 404 is located at the passive optical network physical layer 405 (PON-PHY). PON-PHY 405 is configured to send a transmission frame to a convergence device using a PON interface.

[0085] Step 306: The convergence device receives a transmission frame from the ONU.

[0086] In this embodiment, the convergence apparatus performs transmission frame decapsulation processing to obtain an XGEM frame in the payload region of the transmission frame.

[0087] As shown in FIG. 4, the PON-PHY 407 of the convergence device 406 receives a transmission frame using the PON interface.

[0088] Step 307: The convergence device receives the channel frame carried in the transmission frame.

[0089] First, when receiving a transmission frame, the convergence device may extract an XGEM frame from the payload region of the transmission frame.

[0090] As shown in FIG. 4, the XGTC layer 408 of the convergence device 406 is located on the PON-PHY 407. The XGTC layer 408 receives a transmission frame from the PON-PHY 407, so that the XGTC layer 408 can extract the XGEM frame from the transmission frame. Specifically, the XGTC layer 408 may block the XGEM frame header based on the XGTC frame bandwidth map information and then retrieve the XGEM frame.

[0091] The convergence device then retrieves the channel frame from the payload region of the XGEM frame. In particular, upon receiving an XGEM frame, the convergence device may obtain indication information carried in a header of the XGEM frame, such that the convergence device can determine, based on this information, that a channel frame is carried in the payload regions of the XGEM frame.

[0092] As shown in FIG. 4, the XGEM layer 409 of the convergence device 406 is located at the XGTC layer 408. The XGEM layer is configured to receive a channel frame carried in an XGEM frame.

[0093] Step 308: The convergence device sends a channel frame to the OTN device.

[0094] In this embodiment, the convergence apparatus determines, based on the indication information, that the data carried in the payload area of the XGEM frame is a channel frame. The convergence device determines that the method of transmitting the channel frame is a method without decapsulation between the optical transport network and the access network.

[0095] From the descriptions shown in FIGS. 2, it can be learned that the convergence device shown in this embodiment has an OLT device function and an OTN device function. For example, as shown in FIG. 4, that the convergence device 406 has an OLT function indicates that the convergence device 406 has a PON-PHY 407, an XGTC layer 408 and an XGEM layer 409, and that the convergence device 406 has an OTN device function indicates that the convergence device 406 has a 411 LO ODU level, a 412 HO ODU level and a 413 OTN-L0 level. The LO ODU layer 411 represents the lower order optical data unit (ODU) layer. The HO ODU layer 412 is a higher order ODU layer. In another example, the convergence device 406 may alternatively have only one ODU layer, and the link layer 410 on the convergence device side is configured to encapsulate the link frames in the ODU layer.

[0096] As shown in FIG. 4, the convergence device side channel layer 410 is located in the convergence device 406 shown in this embodiment. The convergence device side channel layer 410 is located at both the XGEM layer 409 and the LO ODU layer 411. The convergence device 406 may implement the function of connecting the optical transport network and the access network based on the link layer 410 on the convergence device side.

[0097] When the convergence device-side link layer 410 receives a channel frame from the XGEM layer 409, the convergence device-side link layer 410 may directly encapsulate the link frame into a low-order ODU of the LO ODU layer 411. It can be learned that the link layer 410 on the convergence device side can send a link frame from the access network to the optical transport network without decapsulating the link frame.

[0098] To better understand the difference between the method shown in this embodiment and the existing solution, comparative descriptions are given below with reference to FIGS. 4 and fig. 5. Fig. 5 presents an exemplary protocol stack diagram of a communication system in accordance with an existing solution.

[0099] As shown in FIG. 5, when the ONU 501 receives service data from a user-side device, the ONU 501 may sequentially perform processing based on the XGEM layer 503, the XGTC layer 504, and the PON-PHY 505 to send to the OLT 506 an XGTC frame that carries the service data. In particular, as shown in FIG. 5, since the link layer is not located on the ONU 501 side, the XGEM layer 503 directly encapsulates the overhead in the XGEM frame. For specific descriptions of the XGTC layer 504 and PON-PHY 505, refer to the corresponding descriptions in FIGS. 4. Details are not repeated.

[00100] PON-PHY 507 OLT 506 shown in FIG. 5 is configured to receive a transmission frame using a PON interface. The XGTC layer 508 is configured to decapsulate the transmission frame to obtain an XGEM frame. The XGEM layer 509 is configured to obtain overhead by decapsulating the XGEM frame. The XGEM layer 509 is further configured to convert the service data into an Ethernet frame and send the Ethernet frame to switching device 510. Switching device 510 forwards the Ethernet frame to OTN device 511 so that OTN device 511 can obtain the service data by parsing the Ethernet frame. It can be learned that based on the communication system shown in FIG. 5, XGEM frame decapsulation processing needs to be performed to obtain the overhead data, and then the overhead data is transmitted from the access network to the optical transport network using the Ethernet interface.

[00101] As shown in FIG. The 4 XGEM layer 409 shown in this embodiment performs decapsulation processing on the XGEM frame to obtain a channel frame. The convergence device no longer decapsulates the channel frame. The link layer 410 on the convergence device side may directly encapsulate the link frame in the LO ODU layer 411. After the HO ODU layer 412 and the OTN-L0 layer 413 sequentially perform processing, an optical transport network (OTN) frame that carries the channel frame is sent to the OTN device 414.

[00102] The OTN side channel layer 415 is located in the OTN device 414, and the OTN side channel layer 415 is configured to obtain overhead data by decapsulating the channel frame. The OTN side channel layer 415 is further configured to send service data to the network server using a service network interface (SNI).

[00103] It can be learned that in this embodiment, a hard pipeline can be created to transmit a channel frame between the convergence device and the ONU to realize an end-to-end connection between the optical transport network and the access network. In particular, as shown in FIG. 4, a hard pipeline for channel frame transmission can be established between the access network and the optical transport network using a link layer 402 on the ONU side and a link layer 410 on the convergence device side. A hard pipeline is a pipeline that can effectively ensure that transmission is not interrupted and no packet loss occurs during the transmission of a channel frame. The frame transmission performance of a channel can be directly monitored by a rigid pipeline, which effectively reduces the complexity of monitoring. In a process in which a channel frame is transmitted between an access network and an optical transport network in a manner without decapsulation, a transmission delay in transmitting overhead data between the access network and an optical transport network is effectively reduced.

[00104] The following describes with reference to FIG. 6, another embodiment of the service data transmission method provided in this application. The embodiment shown in FIG. 6 specifically describes how to process a channel frame to form an intermediate frame and how to implement a process for transmitting overhead data in the uplink based on the intermediate frame.

[00105] Step 601: The ONU receives service data from the user-side device.

[00106] Step 602: The ONU encapsulates the overhead data in a channel frame.

[00107] For specific processes for performing step 601 and step 602, refer to the respective descriptions of step 301 and step 302 shown in FIG. 3. The details are not described here again.

[00108] Step 603: The ONU processes the channel frame to generate an intermediate frame.

[00109] In this embodiment, the ONU needs to process the channel frame to generate an intermediate frame, and then encapsulate in the payload region of the XGEM frame the intermediate frame that carries the overhead data. The specific method of processing a channel frame in this embodiment is not limited as long as the second number of bytes corresponding to the intermediate frame generated after processing is less than or equal to the first number of bytes. The first number of bytes is the number of bytes corresponding to the payload area of the XGEM frames. The following describes several optional methods for generating a tween frame.

[00110] Method 1:

[00111] Thus, if the second number of bytes corresponding to the channel frame is greater than the first number of bytes, the ONU may divide the channel frame to generate a plurality of intermediate frames. The detailed process is as follows:

[00112] The ONU receives the division parameter. The division parameter is the quotient between the second number of bytes used as the dividend and the first number of bytes used as the divisor.

[00113] The ONU evenly divides the channel frame based on the division parameter to form intermediate frames. The number of intermediate frames is equal to the division parameter. If the division parameter is N, then, for example, the specified division parameter N is a positive integer greater than 1. The ONU can evenly divide the channel frame into N parts. Each part obtained by uniformly dividing a channel frame is an intermediate frame shown in this embodiment.

[00114] In this embodiment, an example in which a channel frame is divided evenly is used for exemplary description. In another example, the channel frame may alternatively be divided unevenly, provided that the number of bytes corresponding to each intermediate frame is less than or equal to the first number of bytes.

[00115] To better understand this method, the method is described below with reference to a specific example.

[00116] FIG. 7 is an exemplary service data encapsulation diagram according to the present invention. The following first describes the prerequisites for this example:

[00117] Precondition a: The ONU sends a transmission frame in the slot specified by the convergence device, and the frame rate for the transmission frame is 8000 times per second.

[00118] Precondition b: The overhead data bandwidth is 3 megabits per second (Mbps).

[00119] Precondition c: The second number of bytes corresponding to the channel frame is 192 bytes.

[00120] First, the ONU encapsulates overhead data 701 in channel frame 702. For a specific execution process, refer to step 601 and step 602.

[00121] The ONU may then calculate the first number of bytes based on precondition a and precondition b. Specifically, 3 Mbps = 3072 kbps (kilobits per second) = 3,072,000 bits (bits per second). If the first number of bytes is set to X, X * 8000 * 8=3072000 bps. X=48 bytes can be received.

[00122] The ONU may then determine the division parameter based on the first number of bytes and the precondition c. Specifically, when the ONU determines that the second number of bytes used as the dividend is 192 and the first number of bytes used as the divisor is 48, the ONU determines that the second number of bytes/first number of bytes is 192/48=4 . In this case, the ONU determines that the division parameter = 4, so that the ONU can evenly divide the channel frame to form four intermediate frames 703. In addition, the number of bytes corresponding to each intermediate frame 703 is 192/4=48.

[00123] It can be learned that in this example, if the second number of bytes used as the dividend can be exactly divided by the first number of bytes used as the divisor, the ONU can directly evenly divide the channel frame based on the division parameter.

[00124] The following example is described using an example in which the second number of bytes used as the dividend cannot be exactly divided by the first number of bytes used as the divisor. The following first describes the prerequisites for this example:

[00125] Precondition a: The ONU sends a transmission frame in the slot specified by the convergence device, and the frame rate for the transmission frame is 8000 times per second.

[00126] Precondition b: The overhead data bandwidth is 10 Mbps.

[00127] Precondition c: The second number of bytes corresponding to the channel frame is 350 bytes.

[00128] The ONU may calculate the first number of bytes based on precondition a and precondition b. Specifically, if the first number of bytes is set to X, X*8000*8=10240000 bits. X=160 bytes can be received.

[00129] The ONU may then determine the division parameter based on the first number of bytes and the precondition c. Specifically, when the ONU determines that the second number of bytes used as the dividend is 350 and the first number of bytes used as the divisor is 160, the ONU determines the second number of bytes/first number of bytes is 350/160=2.18 . In this case, the ONU determines that the division parameter is 2, so that the ONU can evenly divide the channel frame to form two intermediate frames. In addition, the number of bytes corresponding to each intermediate frame is 350/2=175.

[00130] In this example, if the second number of bytes used as the dividend cannot be accurately divided by the first number of bytes used as the divisor, the ONU may directly evenly divide the channel frame based on the division parameter.

[00131] Method 2:

[00132] In the previous method 1, an example in which a channel frame is divided into intermediate frames is used for description. Thus, an example is used for description in which a plurality of channel frames are combined to form an intermediate frame.

[00133] Thus, if the second number of bytes is less than or equal to the first number of bytes, the ONU combines a plurality of channel frames to form an intermediate frame. Thus, the number of channel frames included in one intermediate frame is not limited as long as the number of bytes corresponding to the intermediate frame is less than or equal to the first number of bytes. The following describes how the ONU combines multiple channel frames to form an intermediate frame.

[00134] First, the ONU may determine the number of combined frames, where the number of combined frames is the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor.

[00135] Then, if the ONU determines that the channel frame satisfies the combining condition, the ONU combines the channel frames, the number of which is the number of combining frames, to form an intermediate frame. The combination condition is that the second number of bytes is less than or equal to the first number of bytes. The combining condition may further include that the number of combined frames is a positive integer greater than 1.

[00136] For better understanding, descriptions are given below with reference to an example. Fig. 8 is another exemplary service data encapsulation diagram according to the present invention. Thus, for example, the second number of bytes corresponding to each channel frame 802 that carries overhead 801 is 24. In an example in which the ONU determines that the number of first bytes is 72, the ONU may determine that the number of combined frames is 72/ 24=3 so that the ONU can determine that the channel frame meets the combining condition, and therefore the ONU can combine three channel frames to form one intermediate frame 803. In this case, the number of bytes corresponding to the intermediate frame 803 is 24*3= 72.

[00137] Step 604: The ONU encapsulates an intermediate frame in the payload region of the XGEM frame.

[00138] After the ONU receives the intermediate frame, the ONU may encapsulate the intermediate frame in the payload region of the XGEM frame.

[00139] In this embodiment, an example is used for exemplary description in which an intermediate frame is encapsulated in a payload region of an XGEM frame. In another optional example, the ONU may directly encapsulate a channel frame in the payload region of an XGEM frame without processing the channel frame.

[00140] In particular, when determining that the channel frame meets the direct encapsulation condition, the ONU may directly encapsulate the channel frame in the payload region of the XGEM frame. The condition for direct encapsulation is that the second number of bytes is less than or equal to the first number of bytes. The direct encapsulation condition may further include that the number of combined frames is 1. For specific descriptions of the number of combined frames, refer to block 603. The details are not repeated. For example, if the second number of bytes corresponding to a channel frame is 192 and the first number of bytes is 200, the ONU may directly encapsulate the channel frame in the payload area of the XGEM frame.

[00141] Step 605: The ONU encapsulates the XGEM frame in a transmit frame.

[00142] In this embodiment, the transmission frame is an XGTC frame. In particular, the ONU may encapsulate an XGEM frame within the payload area of an XGTC frame. For better understanding, those shown in FIGS. are still used in the following. 7 as an example for description.

[00143] As shown in FIG. 7, since the frame rate for the transmission frame shown in this embodiment is 8000 times per second, the slot occupied by each transmission frame is 125 microseconds (μs). The ONU may encapsulate an XGEM frame 704 within a payload region of an XGTC frame 705.

[00144] Step 606: The ONU sends a transmit frame to the convergence device.

[00145] Step 607: The convergence device receives a transmission frame from the ONU.

[00146] For specific descriptions of step 606 and step 607, refer to the corresponding descriptions of step 305 and step 306, which are shown in FIG. 3. The details are not described here again.

[00147] Step 608: The convergence device receives the channel frame carried in the transmit frame.

[00148] First, when receiving a transmission frame, the convergence device may extract an XGEM frame from the payload region of the transmission frame.

[00149] The convergence device then extracts the intermediate frame from the payload region of the XGEM frame. In particular, after receiving an XGEM frame, the convergence device can obtain indication information carried in the XGEM frame overhead information, so that the convergence device can determine, based on the indication information, that the data carried in the payload area of the XGEM frame is an intermediate frame.

[00150] The convergence device then processes the intermediate frame to form a channel frame. The convergence device may perform the reverse process of step 603 shown in FIG. 6 to implement the process of obtaining a channel frame based on an intermediate frame. For better understanding, the following describes with reference to step 603 a specific process for obtaining a channel frame based on an intermediate frame.

[00151] Method 1:

[00152] If the ONU splits a channel frame to form multiple intermediate frames (for details, refer to method 1 shown in step 603), the convergence device may combine multiple intermediate frames carrying the same service into a channel frame in a framing manner.

[00153] The example shown in FIG. 7 is still in use today. When the convergence device receives four XGTC frames 705 shown in FIG. 7, the convergence device may decapsulate four XGTC frames 705 to obtain XGEM frames 704. The convergence apparatus determines, based on indication information included in the overhead information of XGEM frames 704, that the data carried in XGEM frames 704 are intermediate frames. The convergence apparatus determines, based on the overhead information of XGEM frames 704, intermediate frames that carry the same overhead, that is, the four intermediate frames 703 shown in FIG. 7 such that the convergence device can combine the four intermediate frames 703 into an overhead encapsulation sequence to form a channel frame.

[00154] Method 2:

[00155] If the ONU combines multiple channel frames to form an intermediate frame (for details, refer to Method 2 shown in step 603), then the intermediate frame carries multiple channel frames. The convergence device may split the intermediate frame to form multiple channel frames.

[00156] The example shown in FIG. 8 is still in use today. When the convergence device receives an XGEM frame 804 from an XGTC frame, the convergence device determines based on the overhead information of the XGEM frame 804 that the data carried in the XGEM frame 804 is an intermediate frame. The convergence apparatus determines, based on the XGEM frame overhead, a plurality of channel frames included in the intermediate frame 803, so that the convergence apparatus can divide the intermediate frame 803 to form three channel frames 802 shown in FIG. 8.

[00157] Step 609: The convergence device sends a channel frame to the OTN device.

[00158] For the specific process of step 609, refer to step 308 shown in FIG. 3. The details are not described here again.

[00159] In this embodiment, when the frame rate for the XGEM frame does not correspond to the frame rate for the channel frame, and the second number of bytes corresponding to the channel frame is fixed, the ONU can process the channel frame to generate an intermediate frame, so that the ONU can successfully encapsulate intermediate frame in the payload region of the XGEM frame, thereby increasing the likelihood of successful encapsulation of the link frame in the payload region of the XGEM frame and avoiding packet loss in the link frame. This effectively reduces the latency when encapsulating a channel frame in an XGEM frame.

[00160] In the embodiment shown in FIG. 6, a method for transmitting channel frames that carry the same service data from an access network to an optical transport network is used as an example to describe. The following describes with reference to FIG. 9, how to transmit channel frames that carry different service data from the access network to the optical transport network.

[00161] In this embodiment, the number of service data fragments transmitted by the ONU to the convergence device is not limited. For better understanding, in this embodiment, an example in which an ONU transmits two pieces of service data to a convergence device is used for an example description. If the ONU needs to transmit more than two pieces of overhead data to the convergence device, one skilled in the art can obviously obtain a method based on the method shown in this embodiment without creative efforts. This is not described in detail in this embodiment.

[00162] Step 901: The ONU receives the first overhead data and the second overhead data.

[00163] The specific service types of the first service data and the second service data are not limited in this embodiment. For example, the service type of the first service data is a live video service, and the service type of the second service data is a video on demand service.

[00164] Step 902: The ONU encapsulates the first overhead data in the first channel frame.

[00165] Step 903: The ONU encapsulates the second overhead data in a second channel frame.

[00166] The specific processes shown at step 902 and step 903 relate to the process of encapsulating overhead data in a channel frame shown in the above method embodiments. The details are not described here again. There is no execution time sequence limitation between block 902 and block 903.

[00167] Step 904: The ONU processes the first channel frame to generate a first intermediate frame.

[00168] Step 905: The ONU processes the second channel frame to generate a second intermediate frame.

[00169] The specific processes shown at step 904 and step 905 relate to the channel frame processing process for generating an intermediate frame shown in the above method embodiments. The details are not described here again. The generated first intermediate frame is used to carry the first overhead data, and the generated second intermediate frame is used to carry the second overhead data. There is no execution time sequence limitation between block 904 and block 905.

[00170] Step 906: The ONU receives the first service slice belonging to the first intermediate frame.

[00171] Step 907: The ONU receives a second service slice belonging to the second intermediate frame.

[00172] The ONU shown in this embodiment must separately extract at least a few bytes from the first intermediate frame to form the first service slice. In addition, the ONU needs to extract at least a few bytes from the second intermediate frame to form the second service slice. For better understanding, a specific method in which the ONU obtains the first service slice and the second service slice is described below.

[00173] First, the ONU determines the target throughput ratio. The target bandwidth ratio is the ratio between the bandwidth occupied by the first service data and the bandwidth occupied by the second service data. For example, if the bandwidth occupied by the first overhead is 5 Mbps and the bandwidth occupied by the second overhead is 4 Mbps, the ONU may determine that the target throughput ratio is 5/4.

[00174] The ONU then retrieves the first service slice and the second service slice based on the target throughput ratio. The ratio between the number of bytes included in the first service slice and the number of bytes included in the second slice is equal to the target throughput ratio.

[00175] Still referring to the previous example, that is, the example in which the target throughput ratio is 5/4, the ONU may extract 5 bytes from the first intermediate frame to form the first service slice, and the ONU may additionally extract 4 bytes from the second intermediate frame to form the second service slice. It can be learned that the ONU only needs to separately extract the first service slice from the first intermediate frame and the second service slice from the second intermediate frame based on an integer multiple of the target throughput ratio.

[00176] Step 908: The ONU encapsulates the first service slice and the second service slice in the payload region of the interleaved XGEM frame.

[00177] To better understand the method shown in this embodiment, the method will now be described with reference to FIG. 10. In this example, the overhead bandwidth occupied by the first overhead data 1010 is 4 Mbps, and the overhead bandwidth occupied by the second overhead data 1020 is 6 Mbps.

[00178] As shown in FIG. 10, the ONU generates first intermediate frames for the first channel frame 1011, for example, the first intermediate frame 1012, the first intermediate frame 1013 and the first intermediate frame 1014, which are shown in FIG. 10. The ONU generates second intermediate frames for the second channel frame 1021, for example, the second intermediate frame 1022 and the second intermediate frame 1023, which are shown in FIG. 10.

[00179] The ONU may determine based on the overhead bandwidth occupied by the first overhead data 1010 and the overhead bandwidth occupied by the second overhead data 1020 that the target bandwidth ratio is 4/6=2/3.

[00180] The ONU may extract 2 bytes from the first intermediate frame 1012 to form the first service slice 1015. The ONU may further extract 3 bytes from the second intermediate frame 1022 to form the second service slice 1024.

[00181] Therefore, the ONU may encapsulate the first service slice 1015 and the second service slice 1024 in the payload region of the XGEM frame 1030. The process is carried out by polling until the first overhead data 1010 and the second overhead data 1020 are completely encapsulated in the XGEM frame.

[00182] Step 909: The ONU encapsulates the XGEM frame in a transmit frame.

[00183] However, as shown in FIG. 10, the ONU may encapsulate an XGEM frame in a transmission frame 1031. For a specific process, refer to step 605 shown in FIG. 6. Details are not repeated.

[00184] Step 910: The ONU sends a transmit frame to the convergence device.

[00185] Step 911: The convergence device receives a transmission frame from the ONU.

[00186] For the specific processes of step 910 and step 911 that are shown in this embodiment, refer to step 606 and step 607, which are shown in FIG. 6. Specific execution processes are not described again.

[00187] Step 912: The convergence device receives the first channel frame and the second channel frame that are carried in the transmit frame.

[00188] First, when receiving a transmission frame, the convergence device may extract an XGEM frame from the payload region of the transmission frame.

[00189] The convergence device then extracts the first service slice and the second service slice from the payload area of the XGEM frame. In particular, after receiving an XGEM frame, the convergence device may obtain indication information carried in the overhead information of the XGEM frame, so that the convergence device can determine, based on the indication information, that the data carried in the payload area of the XGEM frame represents a first service slice and a second service slice.

[00190] The convergence device then combines all received first service slices to form a first intermediate frame. The convergence device may further combine all received second service slices to form a second intermediate frame.

[00191] Specifically, when the convergence device receives the first service slice and the second service slice, the convergence device may perform intermediate frame merging based on the number of bytes included in each service slice. The previous example is still used today. The convergence device may determine that the first overhead slices, each of 2 bytes, originate from the same first intermediate frame, and the second overhead slices, each of 3 bytes, originate from the same second intermediate frame.

[00192] The convergence device then processes the first intermediate frame to form the first channel frame. The convergence device may further process the second intermediate frame to form a second channel frame. For a specific process, refer to step 608 shown in FIG. 6. Details are not repeated.

[00193] Step 913: The convergence device sends channel frames to the OTN device.

[00194] For the specific process of step 913 shown in this embodiment, refer to step 609 shown in FIG. 6. Details are not repeated.

[00195] A plurality of hard pipelines may be located in the ONU shown in this embodiment. Each hard pipeline is configured to encapsulate one piece of service data in a channel frame. The channel frame transmission method is a method without decapsulation between an optical transport network and an access network. Since the ONU shown in this embodiment needs to transmit multiple overhead pieces, multiple overhead pieces can be transmitted using various hard pipelines.

[00196] In this embodiment, an example is used for description in which the ONU allocates bandwidth by treating all hard pipelines as a whole. That the ONU allocates bandwidth by treating all hard pipelines as a single entity specifically indicates that the ONU encapsulates all channel frames carrying different overheads within the payload domain of the same interleaved XGEM frame by considering all channel frames , which carry different service data as a single unit.

[00197] Optionally, in another example, the ONU may separately allocate bandwidth for hard pipelines. That is, the ONU encapsulates channel frames carrying different overheads in the payload areas of different XGEM frames.

[00198] In the method shown in this embodiment, the ONU allocates bandwidth by treating all hard pipelines as a whole, so that transmission latency and jitter in transmission overhead are reduced, the utilization of bandwidth allocated by the ONU is effectively improved, and the complexity of dynamic Dynamic bandwidth allocation (DBA) during transmission of overhead data can be effectively reduced.

[00199] The following describes with reference to FIG. 11, a frame format for a transmission frame used to transmit overhead data from an access network to an optical transport network. In this embodiment, an example in which the access network is XGPON is used for exemplary description.

[00200] As shown in FIG. 11, XGTC frame 1101 upstream overhead may include physical layer overhead upstream (PLOu), physical layer OAM upstream (PLOAMu), dynamic report about upstream bandwidth (dynamic bandwidth report upstream, DBRu) and the like.

[00201] The XGEM frame 1103 is carried in the XGTC frame payload regions 1102 of the XGTC frame 1101. The specific number of XGEM frames carried in the XGTC frame payload region 1102 is not limited in this embodiment, that is, the XGTC frame payload region 1102 may contain multiple XGEM frames.

[00202] The payload area of the XGEM frame shown in this embodiment carries channel frame 1104. In fig. 11, an example is used for exemplary description in which the payload area of the XGEM frame 1103 carries the channel frame 1104. In embodiments of the above method, the ONU may alternatively process the channel frame to generate an intermediate frame. In this example, the payload area of XGEM frame 1103 carries an intermediate frame. For specific descriptions, refer to the above method embodiments. The details are not repeated.

[00203] The XGEM frame header 1105 shown in this embodiment includes a payload length indicator (PLI) field, a port identifier field used to support multiport multiplexing, a Key Index field, a last fragment (last fragment, LF) and header error check (HEC) field.

[00204] In this embodiment, the XGEM frame header 1105 further includes a reserved Options field. The options field is used to carry indication information, and the indication information is used to indicate a channel frame. For specific descriptions of the indication information, refer to the above-mentioned method embodiments. The details are not repeated.

[00205] The previous embodiments describe the transmission of overhead data in the uplink direction, and the subsequent ones describe the transmission of overhead data in the downstream direction with reference to FIG. 12.

[00206] Step 1201: The OTN device receives service data from the network server.

[00207] As shown in FIG. 4, the OTN device receives service data from the network server using the service network interface. For specific descriptions of the network server, refer to the server shown in FIG. 1. Details are not repeated.

[00208] Step 1202: The OTN device encapsulates the overhead data in a channel frame.

[00209] For a specific process in which an OTN device encapsulates overhead in a channel frame, refer to the specific descriptions (e.g., step 302 in FIG. 3 and step 602 in FIG. 6) of ONU encapsulating overhead in a channel frame shown in the above embodiments of the method. The details are not described here again.

[00210] As shown in FIG. 4, an OTN side channel layer 415 may be added to the OTN device. The channel layer 415 on the OTN side is configured to: determine the number of bytes corresponding to the channel frame, and encapsulate the service data in the channel frame. For a specific description of the channel layer 415 on the OTN side, refer to the description of the channel layer 402 on the ONU side in the embodiment shown in FIG. 3. Details are not repeated.

[00211] Step 1203: The OTN device encapsulates the channel frame in an XGEM frame.

[00212] For the specific process of performing step 1203 shown in this embodiment, refer to the process in which the ONU encapsulates a channel frame in an XGEM frame in embodiments of the above method, such as step 303 shown in FIG. 3, step 603 and step 604 shown in FIG. 6, and steps 904-908, which are shown in FIG. 9.

[00213] Step 1204: The OTN device encapsulates the XGEM frame in the transmit frame.

[00214] Step 1205: The OTN device sends a transmission frame to the convergence device.

[00215] Step 1206: The convergence device receives a transmission frame from the OTN device.

[00216] Step 1207: The convergence device receives the channel frame carried in the transmit frame.

[00217] Step 1208: The convergence device sends a channel frame to the ONU.

[00218] For specific processes for performing steps 1204-1208 shown in this embodiment, refer to steps 304-308 shown in FIG. 3, refer to steps 605-609, which are shown in FIG. 6, or refer to steps 909-913, which are shown in FIG. 9. Details are not repeated.

[00219] The channel layer 402 on the ONU side is configured to obtain overhead data by decapsulating the channel frame. The channel layer 402 on the ONU side is further configured to send the received service data to a corresponding device on the user side.

[00220] The difference between the downstream transmission frame shown in this embodiment and the upstream transmission frame shown in the previous method embodiments is that the upstream transmission frame is transmitted in a burst manner, while the transmission in the downstream direction transmission is transmitted in a continuous manner. For a description of the frame format for the transmission frame shown in this embodiment, refer to those shown in FIG. 11. Details are not repeated.

[00221] For specific descriptions of the beneficial effects of the method shown in this embodiment, refer to the descriptions shown in previous embodiments of the method. Details in this embodiment are again not described.

[00222] The following describes with reference to FIG. 13, the first device and the second device in this application. Specifically, when transmitting overhead data in the upstream direction, the first device is an ONU in the previous embodiments, and the second device is a convergence device. When transmitting overhead data in the downstream direction, the first device is the convergence device in the previous embodiments, and the second device is the ONU. Next, specific structures of the first device and the second device are described with reference to different directions of transmission of overhead data.

[00223] When uplinking service data:

[00224] In an exemplary implementation of FIG. 13 may be a design diagram of the first device. The first device includes a processor 1301, a memory 1302, and an optical transceiver 1303. The processor 1301, memory 1302, and the optical transceiver 1303 are connected to each other by a line. The memory 1302 is configured to store program instructions and data.

[00225] In an exemplary implementation, memory 1302 stores program instructions and data that support the steps performed by the ONU in the steps shown in FIG. 3, fig. 6 and fig. 9, and the processor 1301 and the optical transceiver 1303 are configured to perform the method steps performed by the ONU shown in any of the embodiments shown in FIG. 3, fig. 6 and fig. 9.

[00226] In FIG. 13, the optical transceiver 1303 is configured to perform steps 301 and 305, and the processor 1301 is configured to perform steps 302-304. In fig. 6, optical transceiver 1303 is configured to perform steps 601 and 606, and processor 1301 is configured to perform steps 602-605. In fig. 9, optical transceiver 1303 is configured to perform steps 901 and 910, and processor 1301 is configured to perform steps 902-909.

[00227] In another possible implementation of FIG. 13 may alternatively be an exemplary design diagram of the second device. Therefore, in this implementation, memory 1302 stores program instructions and data that support the steps performed by the convergence device in the steps shown in FIG. 3, fig. 6 and fig. 9, and the processor 1301 and the optical transceiver 1303 are configured to perform the method steps performed by the convergence device shown in any of the embodiments shown in FIG. 3, fig. 6 and fig. 9.

[00228] In FIG. 3, the optical transceiver 1303 is configured to perform step 306 and step 308, and the processor 1301 is configured to perform step 307. In FIG. 6, the optical transceiver 1303 is configured to perform step 607 and step 609, and the processor 1301 is configured to perform step 608. In FIG. 9, the optical transceiver 1303 is configured to perform step 911 and step 913, and the processor 1301 is configured to perform step 912.

[00229] When transmitting service data downstream:

[00230] In an exemplary implementation of FIG. 13 may be a design diagram of the first device. Memory 1302 shown in FIG. 13 stores program instructions and data that support the steps performed by the convergence device in the steps shown in FIG. 12, and the processor 1301 and the optical transceiver 1303 are configured to perform the method steps performed by the convergence device shown in FIG. 12. In FIG. 12, the optical transceiver 1303 is configured to perform step 1206 and step 1208, and the processor 1301 is configured to perform step 1207.

[00231] In another possible implementation of FIG. 13 may alternatively be an exemplary design diagram of the second device. Memory 1302 shown in FIG. 13 stores program instructions and data that support the steps performed by the ONU in the steps shown in FIG. 12, and the processor 1301 and the optical transceiver 1303 are configured to perform the method steps performed by the ONU shown in FIG. 12. For specific descriptions of the method steps performed by the ONU, refer to those shown in FIG. 12. Details are not repeated.

[00232] An embodiment of this application further provides a digital processing chip. Circuitry and one or more interfaces that are configured to implement the functions of the aforementioned processor 1301 are integrated into a digital processing chip. When the memory is integrated into a digital processing chip, the digital processing chip may perform the method steps of any one or more of the previous embodiments. When the memory is not integrated into the digital processing chip, the digital processing chip can be connected to external memory through an interface. The digital processing chip implements, based on program code stored in an external memory, the actions performed by the ONU or the convergence device in the above-mentioned embodiments.

[00233] One skilled in the art may appreciate that all or some of the steps of the embodiments may be implemented by a program instructing associated hardware. The program may be stored on a computer-readable storage medium. The above-mentioned storage medium may be a read-only memory, a random access memory, or the like. In particular, for example, the aforementioned processing unit or processor may be a central processing unit, a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a transistor logic device, hardware component or any combination thereof. The performance of functions by hardware or software depends on the specific applications and the state of the design constraints of the technical solutions. One skilled in the art may employ various methods to implement the described functions for each particular application, but such implementation should not be considered beyond the scope of this application.

[00234] When software is used to implement the embodiments, the method steps in the preceding embodiments may be implemented in whole or in part in the form of a computer program product. A computer program product includes one or more computer instructions. When computer program instructions are downloaded and executed on a computer, procedures or functions in accordance with embodiments of this application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer-readable storage medium or may be transmitted from a computer-readable storage medium to another computer-readable storage medium. For example, computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, fiber optic, or digital subscriber line (DSL) ) or wirelessly (such as infrared radiation, radio or microwave radiation). A computer-readable storage medium can be any usable medium accessible to a computer, or a storage device, such as a server or data center, combining one or more usable media. The media used may be magnetic media (eg, floppy disk, hard disk, or magnetic tape), optical media (eg, DVD), or semiconductor media.

[00235] Finally, it should be noted that the preceding descriptions are merely specific implementations of this application and are not intended to limit the scope of this application. Any change or substitution readily detectable by one skilled in the art within the technical scope disclosed in this application shall/shall fall within the scope of protection of this application. Therefore, the scope of protection of the present application should correspond to the scope of protection of the claims.

Claims (69)

1. Method of transmitting service data, including: encapsulating, by the first device, a channel frame in a transmission frame, wherein the channel frame is used to carry service data, the channel frame is transmitted between the optical transport network and the access network in a transmission method without decapsulation, and the transmission frame contains indication information used to indicate the channel frame; And sending the first device a transmission frame to the second device, wherein, before the first device encapsulates the channel frame in the transmission frame, the method further includes: processing, by a first device, a channel frame to generate one or more intermediate frames, wherein a number of bytes corresponding to the one or more intermediate frames is less than or equal to a first number of bytes, and the first number of bytes is a number of bytes corresponding to a payload area of the XGEM frame of a passive optical encapsulation method networks with a capacity of 10 gigabit. 2. The transmission method of claim 1, wherein processing the channel frame by the first device to generate one or more intermediate frames includes: if the second number of bytes is greater than the first number of bytes, dividing by the first device the channel frame to form a plurality of intermediate frames, the second number of bytes being the number of bytes corresponding to the channel frame. 3. The transmission method of claim 2, wherein the first device dividing a channel frame to form a plurality of intermediate frames includes: obtaining, by the first device, a division parameter, wherein the division parameter is a quotient between a second number of bytes used as a dividend and a first number of bytes used as a divisor; And uniformly dividing the channel frame by the first device based on the division parameter to form intermediate frames, wherein the number of intermediate frames is equal to the division parameter. 4. The transmission method of claim 1, wherein the first device processing the channel frame to generate one or more intermediate frames includes: if the second number of bytes is less than or equal to the first number of bytes, combining, by the first device, a plurality of channel frames to form one or more intermediate frames, the second number of bytes being the number of bytes corresponding to the channel frame. 5. The transmission method of claim 4, wherein the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is a positive integer greater than 1. 6. Transfer method according to any one of paragraphs. 1-5, wherein the first device's encapsulation of a channel frame in a transmission frame includes: the first device encapsulating one or more intermediate frames in a payload area of the XGEM frame; And encapsulating, by the first device, an XGEM frame in a transmission frame, wherein the transmission frame is a 10 Gigabit Passive Optical Network Transmission Convergence XGTC frame. 7. Transfer method according to any one of paragraphs. 1-5, in which the first intermediate frame is used to carry the first overhead data, the second intermediate frame is used to carry the second overhead data, and the first device's encapsulation of a channel frame in a transmission frame includes: encapsulation by a first device of a first service slice and a second service slice in a payload domain of an interleaved XGEM frame, wherein the XGEM frame service information carries indication information, the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, and the relationship between the number of bytes contained in the first service slice and the number of bytes contained in the second service slice is equal to the ratio of the throughput between the first service data and the second service data; And encapsulating, by the first device, an XGEM frame in a transmission frame, wherein the transmission frame is an XGTC frame. 8. The transmission method of claim 1, wherein the first device's encapsulation of a channel frame in the transmission frame includes: if the second number of bytes is less than or equal to the first number of bytes, the first device encapsulates the channel frame in the payload area of the XGEM frame, wherein the second number of bytes represents the number of bytes corresponding to the channel frame and the first number of bytes represents the number of bytes corresponding to the payload area XGEM frame; And encapsulating, by the first device, an XGEM frame in a transmission frame, wherein the transmission frame is an XGTC frame. 9. The transmission method according to claim 8, wherein the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is 1. 10. Method of transmitting service data, including: receiving, by the second device, a transmission frame from the first device, wherein the transmission frame contains indication information used to indicate the channel frame; receiving, by a second device, one or more intermediate frames carried in a transmission frame, wherein a number of bytes corresponding to the one or more intermediate frames is less than or equal to a first number of bytes, and the first number of bytes is a number of bytes corresponding to a payload area of the XGEM frame; And processing, by a second device, one or more intermediate frames to obtain a channel frame, wherein the channel frame is used to carry overhead data, and the channel frame is transmitted between the optical transport network and the access network without decapsulation. 11. The transmission method of claim 10, wherein the second device receiving one or more intermediate frames carried in the transmission frame includes: receiving, by the second device, an XGEM frame carried in a transmission frame, wherein the transmission frame is an XGTC frame, and the XGEM frame overhead information carries indication information; receipt by the second device of the first service slice and the second service slice from the XGEM frame, wherein the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, the first intermediate frame is used to carry the first service data, the second intermediate frame is used to carry the second service data data, and the ratio between the number of bytes contained in the first service slice and the number of bytes contained in the second service slice is equal to the ratio of the throughput between the first service data and the second service data; receiving by the second device a first intermediate frame based on the first service slice; And receipt by the second device of a second intermediate frame based on the second service slice. 12. A digital processing chip for transmitting service data, wherein the chip contains a processor and memory, wherein the memory and processor are interconnected, the memory stores instructions, and the processor is configured to perform the method for transmitting service data according to any one of claims. 1-9. 13. A digital processing chip for transmitting service data, wherein the chip contains a processor and memory, wherein the memory and processor are interconnected, the memory stores instructions, and the processor is configured to perform the method for transmitting service data according to any one of claims. 10, 11. 14. The first device for transmitting service data, comprising: a processor, memory, and an optical transceiver, wherein the processor, memory, and optical transceiver are interconnected and the processor calls program code in memory to perform the following steps: encapsulating a channel frame in a transmission frame, wherein the channel frame is used to carry overhead data, the channel frame is transmitted between the optical transport network and the access network without decapsulation, and the transmission frame contains indication information used to indicate the channel frame; And sending the transmission frame to the optical transceiver; wherein the processor is particularly configured to process the channel frame to generate one or more intermediate frames, wherein a number of bytes corresponding to the one or more intermediate frames is less than or equal to a first number of bytes, and the first number of bytes is a number of bytes corresponding to a usable area XGEM frame load; And the optical transceiver is configured to send the transmission frame to the second device. 15. The first device according to claim 14, in which the processor, in particular, is configured to: if the second number of bytes is greater than the first number of bytes, divide the channel frame to form a plurality of intermediate frames, the second number of bytes being the number of bytes corresponding to the channel frame. 16. The first device according to claim 15, in which the processor, in particular, is configured to: obtain a division parameter, wherein the division parameter is the quotient between a second number of bytes used as the dividend and a first number of bytes used as the divisor; And evenly divide the channel frame based on the division parameter to form intermediate frames, with the number of intermediate frames equal to the division parameter. 17. The first device according to claim 14, in which the processor, in particular, is configured to: if the second number of bytes is less than or equal to the first number of bytes, the plurality of channel frames are combined to form one or more intermediate frames, the second number of bytes being the number of bytes corresponding to the channel frame. 18. The first device of claim 17, wherein the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is a positive integer greater than 1. 19. The first device according to any one of paragraphs. 14-18, in which the processor is, in particular, configured to: encapsulate one or more intermediate frames in the payload region of the XGEM frame; And encapsulate the XGEM frame in a transmission frame, where the transmission frame is an XGTC frame. 20. The first device according to any one of paragraphs. 14-18, wherein a first intermediate frame is used to carry first overhead data, a second intermediate frame is used to carry second overhead data, and the processor is specifically configured to: encapsulate a first service slice and a second service slice in a payload region of an interleaved XGEM frame, wherein the XGEM frame overhead carries indication information, the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, and the relationship between the number of bytes contained in the first service slice, and the number of bytes contained in the second service slice is equal to the throughput ratio between the first service data and the second service data; And encapsulate the XGEM frame in a transmission frame, where the transmission frame is an XGTC frame. 21. The first device according to claim 14, in which the processor, in particular, is configured to: if the second number of bytes is less than or equal to the first number of bytes, encapsulate the channel frame in a payload area of the XGEM frame, the second number of bytes being the number of bytes corresponding to the channel frame, and the first number of bytes being the number of bytes corresponding to the payload area of the XGEM frame; And encapsulate the XGEM frame in a transmission frame, where the transmission frame is an XGTC frame. 22. The first device of claim 21, wherein the quotient between the first number of bytes used as the dividend and the second number of bytes used as the divisor is 1. 23. A second device for transmitting service data, comprising: a processor, memory and an optical transceiver, wherein the processor, memory and optical transceiver are connected to each other; the optical transceiver is configured to receive a transmission frame from the first device, wherein the transmission frame contains indication information used to indicate the channel frame; And The processor calls program code in memory to perform the following steps: receiving one or more intermediate frames carried in a transmission frame, wherein a number of bytes corresponding to the one or more intermediate frames is less than or equal to a first number of bytes, and the first number of bytes is a number of bytes corresponding to a payload area of the XGEM frame; And processing by a second device one or more intermediate frames to obtain a channel frame, wherein the channel frame is used to carry overhead data, and the channel frame is transmitted between the optical transport network and the access network without decapsulation. 24. The second device according to claim 23, in which the processor, in particular, is configured to: obtain an XGEM frame carried in a transmission frame, wherein the transmission frame is an XGTC frame, and the XGEM frame overhead information carries indication information; obtain the first service slice and the second service slice from the XGEM frame, wherein the first service slice belongs to the first intermediate frame, the second service slice belongs to the second intermediate frame, the first intermediate frame is used to carry the first service data, the second intermediate frame is used to carry the second service data, and the ratio between the number of bytes contained in the first service slice and the number of bytes contained in the second service slice is equal to the ratio of the throughput between the first service data and the second service data; get the first intermediate frame based on the first service slice; And get the second intermediate frame based on the second service slice.