WO2018119705A1

WO2018119705A1 - Detection method for transmission delay difference between uplink channels, and olt and system

Info

Publication number: WO2018119705A1
Application number: PCT/CN2016/112476
Authority: WO
Inventors: 赵殿博; 殷锦蓉
Original assignee: 华为技术有限公司
Priority date: 2016-12-27
Filing date: 2016-12-27
Publication date: 2018-07-05

Abstract

Provided are a detection method for a transmission delay difference between uplink channels, and an OLT and a system. The method comprises the following steps: an OLT determines, according to a difference between a first receiving time stamp and a second receiving time stamp, a receiving time difference, wherein the first receiving time stamp is used for indicating a receiving time when the OLT receives, on a first uplink channel, first uplink data sent by an optical network unit (ONU); and the second receiving time stamp is used for indicating the receiving time when the OLT receives, on a second uplink channel, second uplink data sent by the ONU; the OLT determines a sending time difference between the first uplink data and the second uplink data; and furthermore, the OLT, according to a difference between the receiving time difference and the sending time difference, determines a transmission delay difference between the first uplink channel and the second uplink channel. The embodiment of the present application improves the precision for measuring a transmission delay difference between different uplink channels, so as to ensure that an OLT accurately completes message reassembly.

Description

Transmission delay difference detection method, OLT and system between uplink channels

Technical field

The present application relates to communication technologies, and in particular, to a transmission delay difference detection method, an OLT, and a system between uplink channels.

Background technique

With the development of Ethernet Passive Optical Network (EPON) technology, in order to meet the greater bandwidth demand in the future, the standard requirements of 100G EPON are proposed. However, due to the limitation of optical device performance in 100G EPON (currently the physical layer can only achieve 25Gbps rate), to reach the system rate of 100Gbps, it is necessary to bind 25Gbps of 4 transmission channels to carry 100Gbps service flow. Generally, the transmitting network element distributes the packets of one service flow to the four transmission channels for transmission. The receiving network element reassembles the packets received by the four transmission channels to form a service flow. Due to the length of the fiber and the different wavelengths of the channels, the transmission delays of the transmission channels are different, so that the time-order relationship of the packets transmitted on the different transmission channels to the receiving network element changes, resulting in out-of-order. In order to ensure that the receiving network element accurately completes the message reassembly, how to measure the transmission delay difference on different transmission channels becomes an urgent problem to be solved.

In the prior art, an optical line terminal (OLT) periodically performs a combination of control packets for the same downlink channel (for example, the downlink channel L0) and different uplink channels (for example, the uplink channel L1 and the uplink channel L2). The Round Trip Time (RTT) measurement obtains the RTT1 of the downlink channel L0 and the uplink channel L1, and the RTT2 of the downlink channel L0 and the uplink channel L2, and then determines the uplink channel L1 and the uplink channel L2 according to the difference between the RTT2 and the RTT1. The delay between transmissions.

On the one hand, in the prior art, the OLT can only periodically perform RTT measurement on the same downlink channel and the combination of different uplink channels by using control packets (for example, at least four control packets), thereby obtaining transmission between different uplink channels. The delay is poor, but the transmission delay difference between channels varies dynamically with the external environment (such as temperature, humidity, etc.); on the other hand, the accuracy of the RTT measurement used in the prior art is not high (as specified in the protocol, the minimum is 16ns). Therefore, the accuracy of the transmission delay difference between different uplink channels obtained by the prior art measurement is not high, and the receiving network element cannot be accurately completed. Message reorganization.

Summary of the invention

The embodiment of the present invention provides a transmission delay difference detection method, an OLT, and a system between uplink channels, which improves the measurement accuracy of transmission delay differences between different uplink channels.

In a first aspect, the embodiment of the present application provides a method for detecting a transmission delay difference between uplink channels, including:

The optical line terminal OLT determines the receiving time difference according to the difference between the first receiving timestamp and the second receiving timestamp. The first receiving timestamp is used to indicate that the OLT receives the optical network unit ONU sent by the OLT on the first uplink channel. a receiving time of the uplink data, where the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

The OLT determines a transmission time difference between the first uplink data and the second uplink data;

The OLT determines a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the received time difference and the transmission time difference.

The OLT determines the receiving time difference according to the difference between the first receiving timestamp and the second receiving timestamp by using the difference of the transmission delay difference between the uplink channels provided by the first aspect; the OLT determines the first uplink data and the second uplink data. The transmission time difference is further; further, the OLT determines a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the reception time difference and the transmission time difference. It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can receive the time difference of the uplink data received on different uplink channels and the corresponding transmission time difference in real time. Directly measuring the transmission delay difference between different uplink channels, wherein the transmission frequency of the uplink data is 2.56 ns, thereby improving the measurement accuracy of the transmission delay difference between different uplink channels, thereby ensuring that the OLT accurately completes Message reorganization.

In a possible design, the OLT determines a transmission time difference between the first uplink data and the second uplink data, including:

The OLT determines the sending time difference according to the difference between the first sending timestamp carried in the first uplink data and the second sending timestamp carried in the second uplink data.

The first sending timestamp is used to indicate that the ONU sends the first uplink data transmission time on the first uplink channel, and the second sending timestamp is used to indicate that the ONU sends the second uplink data transmission time on the second uplink channel.

According to the method for detecting the transmission delay difference between the uplink channels provided by the embodiment, the OLT accurately calculates the difference between the first transmission timestamp carried in the first uplink data and the second transmission timestamp carried in the second uplink data. The transmission time difference is determined, so that the OLT can directly measure the transmission delay difference between different uplink channels according to the receiving time difference of the uplink data received on different uplink channels and the accurate transmission time difference, thereby improving different uplink channels. The measurement accuracy of the transmission delay difference between.

The OLT determines a transmission time difference according to the first uplink data, where the first uplink data carries a difference in transmission time between the first uplink data and the second uplink data determined by the ONU, and the sending time of the first uplink data is later than the sending of the second uplink data. time.

The OLT provides an accurate transmission time difference according to the first uplink data (carrying an accurate transmission time difference), so that the OLT receives the data in different uplink channels in real time according to the method for detecting the transmission delay difference between the uplink channels provided by the embodiment. The receiving time difference of the uplink data and the accurate transmission time difference directly measure the transmission delay difference between different uplink channels, thereby improving the measurement accuracy of the transmission delay difference between different uplink channels.

The OLT determines the sending time difference according to the third sending timestamp and the fourth sending timestamp;

The third sending timestamp is: a timestamp that the OLT sends to the ONU to send the first uplink data on the first uplink channel, and the fourth sending timestamp is: the OLT allocates the second uplink channel on the second uplink channel. The timestamp of the upstream data.

The OLT determines the transmission time difference according to the pre-assigned third transmission timestamp and the fourth transmission timestamp, so that the OLT receives the time difference according to the uplink channel according to the pre-allocated third transmission timestamp and the fourth transmission timestamp. The receiving time difference of the uplink data and the transmission time difference directly measure the transmission delay difference between different uplink channels, thereby improving the measurement accuracy of the transmission delay difference between different uplink channels.

In one possible design, the first transmit timestamp includes: a first clock cycle count; and/or,

The second sending timestamp includes: a second clock cycle count;

The first clock cycle counts as the ONU sends the first uplink data pair on the first uplink channel. The number of clock cycles to be counted, and the second clock cycle count is the number of clock cycles corresponding to the second uplink data sent by the ONU on the second uplink channel.

In a possible design, the OLT determines the transmission time difference according to the difference between the first sending timestamp carried in the first uplink data and the second sending timestamp carried in the second uplink data, including:

The OLT determines the transmission time difference according to the difference between the first clock cycle count and the second clock cycle count and the operating clock of the ONU.

In a second aspect, an embodiment of the present application provides an optical line terminal OLT, including:

a first determining module, configured to determine a receiving time difference according to a difference between the first receiving timestamp and the second receiving timestamp, where the first receiving timestamp is used to indicate that the OLT receives the optical network unit ONU on the first uplink channel The receiving time of the first uplink data that is sent, the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

a second determining module, configured to determine a sending time difference between the first uplink data and the second uplink data;

The third determining module is configured to determine a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the received time difference and the sending time difference.

In one possible design, the second determining module includes:

a first determining unit, configured to determine, according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data, a sending time difference;

In one possible design, the second determining module includes:

a second determining unit, configured to determine, according to the first uplink data, a sending time difference, where the first uplink data carries a sending time difference between the first uplink data and the second uplink data determined by the ONU, and the sending time of the first uplink data is later than The transmission time of the second uplink data.

In one possible design, the second determining module includes:

a third determining unit, configured to determine a sending time difference according to the third sending timestamp and the fourth sending timestamp;

The second sending timestamp includes: a second clock cycle count;

The first clock cycle count is the number of clock cycles corresponding to the first uplink data sent by the ONU on the first uplink channel, and the second clock cycle count is the clock cycle corresponding to the second uplink data sent by the ONU on the second uplink channel. number.

In a possible design, the first determining unit is specifically configured to: determine a transmission time difference according to a difference between the first clock cycle count and the second clock cycle count, and the ONU operating clock.

For the beneficial effects of the OLT provided by the foregoing second aspect and the foregoing possible implementation manners of the second aspect, reference may be made to the beneficial effects of the foregoing possible implementation manners of the first aspect, and details are not described herein.

In a third aspect, the embodiment of the present application provides a transmission delay difference detection system between uplink channels, including:

Optical network unit ONU and optical line terminal OLT of any of the possible aspects of the above second aspect.

For the beneficial effects of the transmission delay difference detection system between the uplink channels provided by the foregoing third aspect, reference may be made to the beneficial effects of the foregoing possible implementation manners of the second aspect, and details are not described herein.

DRAWINGS

1 is a schematic structural diagram of a 100G EPON network according to the present application;

2A is a flowchart of Embodiment 1 of a method for detecting a transmission delay difference between uplink channels provided by the present application;

2B is a schematic diagram 1 of data transmission provided by the present application;

3A is a flowchart of Embodiment 2 of a method for detecting a transmission delay difference between uplink channels provided by the present application;

FIG. 3B is a schematic diagram 2 of data transmission provided by the present application; FIG.

FIG. 3C is a schematic diagram 3 of data transmission provided by the present application; FIG.

FIG. 3D is a schematic diagram showing a frame structure of uplink data provided by the present application;

4A is a flowchart of Embodiment 3 of a method for detecting a transmission delay difference between uplink channels provided by the present application;

4B is a schematic diagram 4 of data transmission provided by the present application;

4C is a schematic diagram 5 of data transmission provided by the present application;

5A is a flowchart of Embodiment 4 of a method for detecting a transmission delay difference between uplink channels provided by the present application;

FIG. 5B is a schematic diagram 4 of data transmission provided by the present application; FIG.

FIG. 5C is a schematic diagram 5 of data transmission provided by the present application; FIG.

FIG. 6 is a schematic structural diagram of Embodiment 1 of an OLT provided by the present application;

FIG. 7 is a schematic structural diagram of Embodiment 2 of an OLT provided by the present application;

FIG. 8 is a schematic structural diagram of an embodiment of a transmission delay difference detecting system between uplink channels provided by the present application.

detailed description

First, the EPON network structure involved in the embodiment of the present application is introduced in detail:

FIG. 1 is a schematic structural diagram of a 100G EPON network according to the present application. As shown in FIG. 1, in a 100 EPON network, an OLT can simultaneously communicate with multiple ONUs through a power splitter (for convenience of description, two ONUs are taken as an example in FIG. 1). In addition, data transmission can be performed between the OLT and the ONU through four transmission channels.

The method, device and system for detecting transmission delay difference between uplink channels provided by the embodiments of the present application are described in detail below with reference to the accompanying drawings.

2A is a flowchart of Embodiment 1 of a method for detecting a transmission delay difference between uplink channels provided by the present application, and FIG. 2B is a schematic diagram 1 of data transmission provided by the present application. The transmission delay difference detection method between uplink channels provided by the present application can be applied to a 100G EPON network. As shown in FIG. 2A, the method in this embodiment may include:

S201: The OLT determines the receiving time difference according to the difference between the first receiving timestamp and the second receiving timestamp.

The first receiving timestamp is used to indicate that the OLT receives the receiving time of the first uplink data sent by the optical network unit ONU on the first uplink channel, and the second receiving timestamp is used to indicate that the OLT receives the second uplink channel. The receiving time of the second uplink data sent by the ONU.

In this embodiment, the working clock of the ONU is a first preset value (such as 390.625 MHz, and 66-bit data is transmitted every 2.56 ns), and different channels of the ONU work under the same clock. For the convenience of description, In the embodiment of the present application, the first uplink channel and the second uplink channel are used as an example. The first uplink channel and the second uplink channel do not refer to a fixed uplink channel, but generally refer to two different uplink channels. Upstream channel.

In this step, the OLT receives the uplink data sent by the ONU on different uplink channels, and records the corresponding receiving timestamp (used to indicate the receiving time of the corresponding uplink data), so as to determine the receiving time difference according to the receiving timestamp corresponding to the different uplink data. As shown in FIG. 2B, in this embodiment, the OLT receives the first uplink data sent by the ONU on the first uplink channel and records the first receiving timestamp t _r1 (instructing the OLT to receive the ONU transmission on the first uplink channel). Receiving time of the first uplink data, and receiving the second uplink data sent by the ONU on the second uplink channel, and recording the second receiving timestamp t _r2 (instructing the OLT to receive the ONU transmission on the second uplink channel) And receiving, by the OLT, the receiving time difference Δt _r between the first uplink data and the second uplink data according to the difference between the first receiving timestamp t _r1 and the second receiving timestamp t _r2 , That is, Δt _r = t _{r1 -} t _r2 .

S202: The OLT determines a sending time difference between the first uplink data and the second uplink data.

In this embodiment, in order to calculate the transmission delay difference between the first uplink channel and the second uplink channel, the OLT needs to acquire the transmission time difference Δt _{t of the} first uplink data and the second uplink data. Optionally, the OLT may know the transmission time difference Δt _{t in} advance, or determine the transmission time difference Δt _t according to the time indication information sent by the ONU.

Optionally, the first implementation manner of the S202 is: the OLT determines the sending time difference Δt _r according to the difference between the first sending timestamp carried in the first uplink data and the second sending timestamp carried in the second uplink data; The first sending timestamp is used to indicate that the ONU sends the first uplink data transmission time on the first uplink channel, and the second sending timestamp is used to indicate that the ONU sends the second uplink data transmission time on the second uplink channel. In this implementation manner, the ONU carries the first sending timestamp in the first uplink data, and carries the second sending timestamp in the second uplink data, so that the OLT can use the first sending timestamp and the second sending timestamp according to the first sending timestamp. The difference is determined by the transmission time difference Δt _r .

Optionally, the second implementation manner of the S202 is: the OLT determines a transmission time difference Δt _r according to the first uplink data, where the first uplink data carries a transmission time difference Δt between the first uplink data and the second uplink data determined by the ONU. _r, the first uplink data transmission time later than the transmitting time of the second uplink data. In this implementation manner, after determining the transmission time difference Δt _r of the first uplink data and the second uplink data, the ONU carries the transmission time difference Δt _r in the first uplink data (the transmission time is later than the transmission time of the second uplink data). So that the OLT directly knows the transmission time difference Δt _r .

Optionally, a third implementation manner of the S202 is: the OLT determines a sending time difference Δt _r according to the third sending timestamp and the fourth sending timestamp; wherein, the third sending timestamp is: the OLT allocates the first time to the ONU. A timestamp of sending the first uplink data on the uplink channel, where the fourth sending timestamp is a timestamp allocated by the OLT to the ONU to send the second uplink data on the second uplink channel. In this implementation manner, the OLT allocates timestamps for transmitting uplink data on different uplink channels for the ONU, so that the ONU sends uplink data on the corresponding uplink channel according to the allocated timestamp. For example, the OLT allocates the ONU on the first uplink channel. The timestamp of sending the first uplink data is the third sending timestamp, and the timestamp of the second uplink data sent by the OLT to the ONU on the second uplink channel is the fourth sending timestamp; as shown in the implementation manner, the OLT is implemented. The transmission time difference Δt _{t is} known in advance.

Certainly, the OLT may determine the time difference of the sending of the first uplink data and the second uplink data by using other methods, which is not limited in this embodiment.

The execution order of the step S201 and the step S202 in the embodiment is not limited (for example, the step S201 is performed first, the step S202 is performed, or the step S202 is performed first, and then the step S201 is performed), and the step S201 and the step S202 can be adjusted according to actual conditions. The order of execution.

S203. The OLT determines, according to a difference between the received time difference and the sending time difference, a transmission delay difference between the first uplink channel and the second uplink channel.

In this embodiment, if there is no transmission delay between the first uplink channel and the second uplink channel, the reception time difference Δt _r and the transmission time difference Δt _t should be equal; if the reception time difference Δt _r is not equal to the transmission time difference Δt _t , then It is indicated that there is a transmission delay between the first uplink channel and the second uplink channel, and the OLT can determine the transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the reception time difference Δt _r and the transmission time difference Δt _t . Δt, ie Δt = Δt _r - Δt _t . It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can receive the time difference of the uplink data received on different uplink channels and the corresponding transmission time difference in real time. Directly measuring the transmission delay difference between different uplink channels, wherein the uplink data transmission frequency is 2.56 ns, thereby improving the measurement accuracy of the transmission delay difference between different uplink channels (measurement accuracy is improved to 2.56 ns) .

In the embodiment of the present application, the OLT determines the receiving time difference according to the difference between the first receiving timestamp and the second receiving timestamp; the OLT determines a sending time difference between the first uplink data and the second uplink data; further, the OLT is configured according to The difference between the received time difference and the transmitted time difference determines the first uplink The difference in transmission delay between the channel and the second upstream channel. It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can receive the time difference of the uplink data received on different uplink channels and the corresponding transmission time difference in real time. Directly measuring the transmission delay difference between different uplink channels, wherein the transmission frequency of the uplink data is 2.56 ns, thereby improving the measurement accuracy of the transmission delay difference between different uplink channels, thereby ensuring that the OLT accurately completes Message reorganization.

FIG. 3A is a flowchart of Embodiment 2 of a method for detecting a transmission delay difference between uplink channels provided by the present application. FIG. 3B is a schematic diagram 2 of data transmission provided by the present application, and FIG. 3C is a schematic diagram 3 of data transmission provided by the present application. As shown in FIG. 3A, the method in this embodiment may include:

S301. The ONU sends the first uplink data to the OLT on the first uplink channel, and sends the second uplink data to the OLT on the second uplink channel.

The first uplink data carries the first sending timestamp t _t1 , where the first sending timestamp t _{t1 is} used to indicate that the ONU sends the first uplink data transmission time on the first uplink channel, and the second uplink data carries the second time. The timestamp t _{t2 is} sent, and the second sending timestamp t _{t2 is} used to indicate the sending time of the second uplink data sent by the ONU on the second uplink channel.

In this step, as shown in FIG. 3B, the first uplink data sent by the ONU on the first uplink channel may carry a first sending timestamp t _t1 (instructing the ONU to send the first uplink data on the first uplink channel). The second transmission data sent by the ONU on the second uplink channel may carry a second transmission timestamp t _t2 (indicating the transmission time of the ONU transmitting the second uplink data on the second uplink channel) . Optionally, the first sending timestamp t _t1 may be carried in a preset field in the first uplink data (for example, an idle field after the delimiter in the frame structure of the first uplink data), and the second sending timestamp t _t2 may be The preset field carried in the second uplink data.

FIG. 3D is a schematic diagram showing the frame structure of the uplink data provided by the present application. As shown in FIG. 3D, the frame structure of the uplink data includes: a Forward Error Correction (FEC) unprotected field, an FEC protection field, and an End of Burst (EOB) field; wherein, the FEC unprotected field The end of the FBR protection field includes: N FEC code words (Codewords, CW for short), N is an integer greater than or equal to 0; the payload portion of each FEC code includes: 27 66-bit code blocks; Alternatively, the sending timestamp may be located in any one of the first two 66-bit code blocks of the FEC CW ₀ corresponding to the uplink data (referred to as a target field), and may of course be located in other fields. This embodiment of the present application does not limit this. Table 1 shows the description information of the target field. For example, as shown in Table 1, the first to second bits of the target field are synchronization sequences. When the value of the current two bits is equal to "10", it represents the target field carrying control information; The 3rd to 10th bits of the field are used to indicate the type of the bearer control information (or the bearer object). When the value of the 3rd to 10th bits is equal to the first preset value, the target field carries the transmission timestamp. When the value of the 3rd to 10th bits is equal to the second preset value, the target field carries the transmission time difference; the 11th to the Xth bits of the target field are used to indicate the bearer object (such as the sending timestamp or the sending time difference). A value, where X is an integer greater than 11 and less than 49; subsequent fields are used to carry ONU identifiers, padding fields, and the like, respectively. Of course, the structure of the target field is not limited to that shown in Table 1, and may be other structures, which is not limited in the embodiment of the present application. In this embodiment, the value of the 3rd to 10th bits of the target field is equal to the first preset value, and the target field carries the transmission timestamp. Correspondingly, the 11th to Xth bits of the target field are used to indicate the sending time. Poke the corresponding value.

Table 1 target field description information

Optionally, the first sending timestamp includes: a first clock cycle count; and/or the second sending timestamp includes: a second clock cycle count. The first clock cycle count is the number of clock cycles corresponding to the first uplink data sent by the ONU on the first uplink channel (for example, the eleventh), and the second clock cycle count is that the ONU sends the second uplink channel on the second uplink channel. The number of clock cycles corresponding to the upstream data (for example, the 10th). Optionally, a counter is set in the ONU (for counting the number of clock cycles after the ONU is powered on, that is, the counter is incremented by 1 every 2.56 ns).

Of course, the first sending timestamp may further include other means for indicating that the ONU is on the first uplink channel. The time indication information of the sending time of the first uplink data is sent, and/or the second sending timestamp may further include other time indication information for indicating the sending time of the second uplink data sent by the ONU on the second uplink channel, This is not limited in the application examples.

S302. The OLT receives the first uplink data that is sent by the ONU on the first uplink channel, and receives the second uplink data that is sent by the ONU on the second uplink channel.

In this step, as shown in FIG. 3C, the OLT receives the first uplink data that is sent by the ONU on the first uplink channel and carries the first transmission timestamp t _t1 and records the first receiving timestamp t _r1 , and receives the ONU in the first The second uplink data carried on the second uplink channel carrying the second transmission timestamp t _t2 and recording the second reception time stamp t _r2 .

S303. The OLT determines, according to a difference between the first receiving timestamp and the second receiving timestamp, a receiving time difference between the first uplink data and the second uplink data.

In this step, the OLT determines, according to the difference between the first receiving timestamp t _r1 and the second receiving timestamp t _r2 , a reception time difference Δt _r between the first uplink data and the second uplink data, that is, Δt _r =t _r1 - t _r2 .

S304. The OLT determines a sending time difference according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data.

In this step, the OLT accurately determines the transmission time difference Δt _t according to the difference between the first transmission timestamp t _t1 carried in the first uplink data and the second transmission timestamp t _t2 carried in the second uplink data, that is, Δt _t =t _t1 -t _t2 .

Optionally, if the first sending timestamp includes: a first clock cycle count c1; and/or, the second sending timestamp includes: a second clock cycle count c2, the OLT counts c1 and the second clock cycle according to the first clock cycle Counting the difference of c2, and the quotient of the operating clock clk of the ONU, determines the transmission time difference Δt _t , that is, Δt _t = (c1 - c2) / clk, where clk is equal to 390.625 MHz.

Certainly, when the first sending timestamp includes other time indication information indicating that the ONU sends the first uplink data transmission time on the first uplink channel, and/or the second sending timestamp includes other means for indicating the ONU in the first When the time indication information of the transmission time of the second uplink data is sent on the two uplink channels, the OLT may determine Δt _t according to other formal formulas of the formula (Δt _t = t _{t1 -} t _t2 ), which is not limited in this embodiment. .

S305. The OLT determines, according to a difference between the received time difference and the sending time difference, a transmission delay difference between the first uplink channel and the second uplink channel.

In this step, the OLT determines the transmission delay difference Δt between the first uplink channel and the second uplink channel according to the difference between the reception time difference Δt _r and the transmission time difference Δt _t , that is, Δt=Δt _r -Δt _t .

In this embodiment, the ONU sends the first uplink data carrying the first sending timestamp to the OLT on the first uplink channel, and sends the second uplink carrying the second sending timestamp to the OLT on the second uplink channel. Data; further, the OLT according to the first receiving timestamp (instructing the OLT to receive the receiving time of the first uplink data sent by the ONU on the first uplink channel) and the second receiving timestamp (for indicating that the OLT is in the second The difference of the receiving time of the second uplink data sent by the ONU on the uplink channel determines the receiving time difference, and the first sending timestamp carried in the first uplink data and the second sending timestamp carried in the second uplink data. The difference is accurately determined by the difference in the transmission time. Further, the OLT determines the transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the reception time difference and the transmission time difference. It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can accurately receive the time difference of the uplink data received on different uplink channels and the accurate transmission time difference in real time. The direct measurement of the transmission delay difference between different uplink channels is performed, thereby further improving the measurement accuracy of the transmission delay difference between different uplink channels.

4A is a flowchart of Embodiment 3 of a method for detecting a transmission delay difference between uplink channels provided by the present application. FIG. 4B is a schematic diagram 4 of data transmission provided by the present application, and FIG. 4C is a schematic diagram 5 of data transmission provided by the present application. As shown in FIG. 4A, the method in this embodiment may include:

S401. The ONU sends the second uplink data to the OLT on the second uplink channel, and sends the first uplink data to the OLT on the first uplink channel.

The first uplink data carries a transmission time difference Δt _r between the first uplink data and the second uplink data determined by the ONU, and the transmission time of the first uplink data is later than the transmission time of the second uplink data.

In this step, as shown in FIG. 4B, the ONU first sends the second uplink data to the OLT on the second uplink channel, and then sends the first uplink data to the OLT on the first uplink channel. Optionally, before transmitting the first uplink data, the ONU determines a transmission time difference Δt _t between the first uplink data and the second uplink data, and carries the transmission time difference Δt _t in the first uplink data, so that the OLT directly knows the transmission time difference. Δt _t . Optionally, the transmission time difference Δt _t may be carried in a preset field in the first uplink data (for example, an idle field after the delimiter in the frame structure of the first uplink data). For the carrying manner of the sending time difference Δt _t , refer to the related content about the carrying manner of the sending timestamp (the first sending timestamp and/or the second sending timestamp). In this application, the sending time difference may be carried in the target field (specifically The description of the target field is not described here. The value of the 3rd to 10th bits of the target field is equal to the second preset value, which means that the target field carries the transmission time difference, correspondingly, the 11th to the Xth of the target field. The bits are used to indicate the value corresponding to the transmission time difference.

Optionally, the sending time difference Δt _t includes: a clock cycle count difference between the first clock cycle count and the second clock cycle count, wherein the first clock cycle count is the ONU corresponding to the first uplink data sent by the ONU. The number of clock cycles, the second clock cycle count is the number of clock cycles corresponding to the second uplink data sent by the ONU on the second uplink channel.

Of course, the transmission time difference Δt _t may further include other time indication information for indicating the difference of the transmission time of the first uplink data and the second uplink data, which is not limited in the embodiment of the present application.

S402. The OLT receives the second uplink data that is sent by the ONU on the second uplink channel, and receives the first uplink data that is sent by the ONU on the first uplink channel.

In this step, as shown in FIG. 4C, the OLT first receives the second uplink data sent by the ONU on the second uplink channel and records the second receiving timestamp t _r2 , and then receives the carried and sent by the ONU on the first uplink channel. The first uplink data of the time difference Δt _t and records the first reception time stamp t _r1 .

S403. The OLT determines, according to a difference between the first receiving timestamp and the second receiving timestamp, a receiving time difference between the first uplink data and the second uplink data.

S404. The OLT determines a transmission time difference according to the first uplink data.

In this step, the OLT directly determines the transmission time difference Δt _t according to the first uplink data (carrying the transmission time difference Δt _t ).

Optionally, if the transmission time difference Δt _r includes: the first clock cycle count and the clock cycle count difference Δc of the second clock cycle count, the OLT determines the transmission time difference according to the quotient of the clock cycle difference Δc and the ONU operating clock clk. Δt _t , ie Δt _t = Δc/clk, where clk is equal to 390.625 MHz.

Of course, when the transmission time difference Δt _t can also include other time indication information indicating the transmission time difference between the first uplink data and the second uplink data, the OLT can formulate according to other formulas of the formula (Δt _t =t _t1 -t _t2 ) The Δt _{t is} determined, which is not limited in the embodiment of the present application.

S405. The OLT determines, according to a difference between the received time difference and the sending time difference, a transmission delay difference between the first uplink channel and the second uplink channel.

In this embodiment, the ONU first sends the second uplink data to the OLT on the second uplink channel, and then sends the transmission time difference to the OLT on the first uplink channel (for indicating that the first uplink data and the second uplink data are accurate. The first uplink data of the transmission time difference; further, the OLT passes the second reception time according to the first reception time stamp (instructing the OLT to receive the reception time of the first uplink data sent by the ONU on the first uplink channel) a difference between the stamping (instructing the OLT to receive the receiving time of the second uplink data sent by the ONU on the second uplink channel), determining the receiving time difference, and determining the accuracy according to the first uplink data (carrying the accurate sending time difference) The transmission time difference is further; further, the OLT determines a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the reception time difference and the transmission time difference. It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can accurately receive the time difference of the uplink data received on different uplink channels and the accurate transmission time difference in real time. The direct measurement of the transmission delay difference between different uplink channels is performed, thereby further improving the measurement accuracy of the transmission delay difference between different uplink channels.

5A is a flowchart of Embodiment 4 of a method for detecting a transmission delay difference between uplink channels provided by the present application. FIG. 5B is a schematic diagram 4 of data transmission provided by the present application, and FIG. 5C is a schematic diagram 5 of data transmission provided by the present application. As shown in FIG. 5A, the method in this embodiment may include:

S501. The ONU sends the first uplink data to the OLT on the first uplink channel according to the authorization indication of the OLT, and sends the second uplink data to the OLT on the second uplink channel.

In this embodiment, the OLT allocates timestamps for transmitting uplink data on different uplink channels for the ONU, so that the ONU sends uplink data on the corresponding uplink channel according to the allocated timestamp. Optionally, the OLT sends an authorization indication to the ONU in advance, where the authorization indication includes: a third timestamp t _t3 allocated by the OLT to the ONU on the first uplink channel, and a second time allocated by the OLT to the ONU. Sending a fourth timestamp t _{t4 of the} second uplink data on the uplink channel.

In this step, as shown in FIG. 5B, the ONU sends the first uplink data on the first uplink channel according to the third timestamp t _t3 , and sends the second uplink data on the second uplink channel according to the fourth time stamp t _t4 .

S502. The OLT receives the first uplink data that is sent by the ONU on the first uplink channel, and receives the second uplink data that is sent by the ONU on the second uplink channel.

In this step, as shown in FIG. 4C, the OLT receives the first uplink data sent by the ONU on the first uplink channel, records the first receiving timestamp t _r1 , and receives the second uplink data sent by the ONU on the second uplink channel. And record the second receiving timestamp t _r2 .

S503. The OLT determines, according to a difference between the first receiving timestamp and the second receiving timestamp, a receiving time difference between the first uplink data and the second uplink data.

S504. The OLT determines a sending time difference according to the third sending timestamp and the fourth sending timestamp.

In this step, the OLT determines the transmission time difference Δt _t , that is, Δt _t =t _t3 -t _t4 according to the difference between the third transmission time stamp t _t3 and the fourth transmission time stamp t _t4 allocated in advance for the ONU.

S505. The OLT determines, according to a difference between the received time difference and the sending time difference, a transmission delay difference between the first uplink channel and the second uplink channel.

In this step, the OLT determines the transmission delay difference Δt between the first uplink channel and the second uplink channel according to the difference between the reception time difference Δt _r and the transmission time difference Δt _t , that is, Δt=Δt _r −Δt _t .

In this embodiment, the ONU sends the first uplink data to the OLT on the first uplink channel and the second uplink data to the OLT on the second uplink channel, according to the third timestamp and the fourth timestamp allocated by the OLT. Further, the OLT passes the second receiving timestamp according to the first receiving timestamp (instructing the OLT to receive the receiving time of the first uplink data sent by the ONU on the first uplink channel) (for indicating that the OLT is in the second Receiving, by the uplink channel, a difference of the receiving time of the second uplink data sent by the ONU, determining a receiving time difference, and determining a sending time difference according to the third sending timestamp and the fourth sending timestamp; further, the OLT is configured according to the receiving time difference and sending The difference of the time differences determines the transmission delay difference between the first uplink channel and the second uplink channel. It can be seen that the method for detecting the transmission delay difference between the uplink channels provided in this embodiment does not depend on the periodic control of the packet, and can directly receive the time difference of the uplink data received on different uplink channels and the transmission time difference in real time. The transmission delay difference between different uplink channels is measured, and therefore, the measurement accuracy of the transmission delay difference between different uplink channels is improved.

In the above embodiments of the present application, the size of the sequence numbers of the foregoing processes does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not be implemented in the implementation process of the embodiment of the present application. Any restrictions.

FIG. 6 is a schematic structural diagram of Embodiment 1 of an OLT provided by the present application. As shown in FIG. 6, the OLT 60 provided in this embodiment includes:

The first determining module 601 is configured to determine, according to a difference between the first receiving timestamp and the second receiving timestamp, a receiving time difference, where the first receiving timestamp is used to indicate that the OLT receives the optical network unit on the first uplink channel. The receiving time of the first uplink data sent by the ONU, where the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

The second determining module 602 is configured to determine a sending time difference between the first uplink data and the second uplink data.

The third determining module 603 is configured to determine a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the received time difference and the sending time difference.

Optionally, the second determining module 602 includes:

Optionally, the first sending timestamp includes: a first clock cycle count; and/or,

The second sending timestamp includes: a second clock cycle count;

The first clock cycle count is the number of clock cycles corresponding to the first uplink data sent by the ONU on the first uplink channel, and the second clock cycle count is the ONU sent on the second uplink channel. The number of clock cycles corresponding to the row data.

Optionally, the first determining unit is specifically configured to: determine a sending time difference according to a difference between the first clock cycle count and the second clock cycle count, and a quotient of the ONU operating clock.

The OLT provided by this embodiment may be used to implement the technical solution of any embodiment of the foregoing method for detecting the delay of the transmission delay between the uplink channels in the present application. The implementation principle and technical effects are similar, and details are not described herein again.

FIG. 7 is a schematic structural diagram of Embodiment 2 of an OLT provided by the present application. As shown in FIG. 7, the OLT 70 provided in this embodiment may include: a processor 701, a memory 702, and a transceiver 703; both the memory 702 and the transceiver 703 are connected to the processor 701. The transceiver 703 is configured to send and receive data, the memory 702 is configured to store execution instructions, and the processor 701 is configured to execute execution instructions in the memory 702 to enable the OLT 70 to perform the following operations:

Determining, according to a difference between the first receiving timestamp and the second receiving timestamp, a receiving time difference, where the first receiving timestamp is used to indicate that the OLT receives the first uplink data sent by the optical network unit ONU on the first uplink channel. Receiving time, the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

Determining a transmission time difference between the first uplink data and the second uplink data;

And determining a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the received time difference and the sending time difference.

Optionally, determining a sending time difference between the first uplink data and the second uplink data, including:

Determining a transmission time difference according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data;

Determining a transmission time difference according to the first uplink data, where the first uplink data carries a transmission time difference between the first uplink data and the second uplink data determined by the ONU, and the sending time of the first uplink data is later than the sending time of the second uplink data. .

Determining a transmission time difference according to the third sending timestamp and the fourth sending timestamp;

The second sending timestamp includes: a second clock cycle count;

Optionally, the sending time difference is determined according to a difference between the first sending timestamp carried in the first uplink data and the second sending timestamp carried in the second uplink data, including:

The transmission time difference is determined according to the difference between the first clock cycle count and the second clock cycle count and the operating clock of the ONU.

FIG. 8 is a schematic structural diagram of an embodiment of a transmission delay difference detecting system between uplink channels provided by the present application. As shown in FIG. 8, the transmission delay difference detecting system 80 between the uplink channels provided in this embodiment includes: an ONU 801 and an OLT 802. The OLT 802 can adopt the foregoing OLT embodiment 1 and the structure of the second embodiment, and correspondingly, the technical solution in the foregoing method for detecting the delay difference between the uplink channels can be executed, and the implementation principle and the technical effect are similar. , will not repeat them here.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of cells is only a logical function division. In actual implementation, there may be another division manner. For example, multiple units or components may be combined or integrated. Go to another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of hardware plus software functional units.

The above-described integrated unit implemented in the form of a software functional unit can be stored in a computer readable storage medium. The above software functional unit is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to perform part of the steps of the method of various embodiments of the present application. .

A person skilled in the art can clearly understand that for the convenience and brevity of the description, only the division of each functional module described above is exemplified. In practical applications, the above function assignment can be completed by different functional modules as needed, that is, the device is installed. The internal structure is divided into different functional modules to perform all or part of the functions described above. For the specific working process of the device described above, refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

It will be understood by those skilled in the art that the various numbers of the first, second, etc., which are referred to herein, are merely for convenience of description and are not intended to limit the scope of the embodiments of the present application.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to the program instructions. The foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing storage medium includes: a read-only memory (Read-Only Memory, ROM for short), a random access memory (RAM), a disk, or a disk. A variety of media such as optical discs that can store program code.

Claims

A method for detecting a transmission delay difference between uplink channels, characterized in that:

The optical line terminal OLT determines the receiving time difference according to the difference between the first receiving timestamp and the second receiving timestamp. The first receiving timestamp is used to indicate that the OLT receives the optical network unit on the first uplink channel. a receiving time of the first uplink data sent by the ONU, where the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

Determining, by the OLT, a sending time difference between the first uplink data and the second uplink data;

The OLT determines a transmission delay difference between the first uplink channel and the second uplink channel according to a difference between the receiving time difference and the sending time difference.
The method according to claim 1, wherein the OLT determines a transmission time difference between the first uplink data and the second uplink data, including:

Determining, by the OLT, the sending time difference according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data;

The first sending timestamp is used to indicate that the ONU sends the sending time of the first uplink data on the first uplink channel, and the second sending timestamp is used to indicate that the ONU is in the Sending time of the second uplink data on the second uplink channel.
The method according to claim 1, wherein the OLT determines a transmission time difference between the first uplink data and the second uplink data, including:

Determining, by the OLT, the sending time difference according to the first uplink data, where the first uplink data carries a sending time difference between the first uplink data and the second uplink data determined by the ONU, where The sending time of the first uplink data is later than the sending time of the second uplink data.
The method according to claim 1, wherein the OLT determines a transmission time difference between the first uplink data and the second uplink data, including:

Determining, by the OLT, the sending time difference according to the third sending timestamp and the fourth sending timestamp;

The third sending timestamp is: a timestamp that the OLT sends to the ONU to send the first uplink data on the first uplink channel, and the fourth sending timestamp is: The time that the OLT allocates the second uplink data on the second uplink channel allocated by the OLT to the ONU. stamp.
The method according to claim 2, wherein the first transmission time stamp comprises: a first clock cycle count; and/or,

The second sending timestamp includes: a second clock cycle count;

The first clock cycle count is the number of clock cycles corresponding to the first uplink data sent by the ONU on the first uplink channel, and the second clock cycle count is the ONU in the first The number of clock cycles corresponding to the second uplink data is sent on the two uplink channels.
The method according to claim 5, wherein the OLT is different according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data, Determining the difference in transmission time, including:

The OLT determines the transmission time difference according to a difference between the first clock cycle count and the second clock cycle count, and a quotient of the ONU operating clock.
An optical line terminal OLT, comprising:

a first determining module, configured to determine a receiving time difference according to a difference between the first receiving timestamp and the second receiving timestamp, where the first receiving timestamp is used to indicate that the OLT receives the first uplink channel a receiving time of the first uplink data sent by the ONU by the optical network unit, the second receiving timestamp is used to indicate that the OLT receives the receiving time of the second uplink data sent by the ONU on the second uplink channel;

a second determining module, configured to determine a sending time difference between the first uplink data and the second uplink data;

The third determining module is configured to determine a transmission delay difference between the first uplink channel and the second uplink channel according to the difference between the receiving time difference and the sending time difference.
The OLT according to claim 7, wherein the second determining module comprises:

a first determining unit, configured to determine, according to a difference between a first sending timestamp carried in the first uplink data and a second sending timestamp carried in the second uplink data, the sending time difference;

The first sending timestamp is used to indicate that the ONU sends the sending time of the first uplink data on the first uplink channel, and the second sending timestamp is used to indicate that the ONU is in the Sending time of the second uplink data on the second uplink channel.
The OLT according to claim 7, wherein the second determining module comprises:

a second determining unit, configured to determine, according to the first uplink data, the sending time difference; The first uplink data carries a difference in transmission time between the first uplink data and the second uplink data determined by the ONU, and the sending time of the first uplink data is later than the second uplink data. Send time.
The OLT according to claim 7, wherein the second determining module comprises:

a third determining unit, configured to determine the sending time difference according to the third sending timestamp and the fourth sending timestamp;

The third sending timestamp is: a timestamp that the OLT sends to the ONU to send the first uplink data on the first uplink channel, and the fourth sending timestamp is: a timestamp that the OLT sends to the ONU to send the second uplink data on the second uplink channel.
The OLT according to claim 8, wherein the first transmission time stamp comprises: a first clock cycle count; and/or,

The second sending timestamp includes: a second clock cycle count;

The first clock cycle count is the number of clock cycles corresponding to the first uplink data sent by the ONU on the first uplink channel, and the second clock cycle count is the ONU in the first The number of clock cycles corresponding to the second uplink data is sent on the two uplink channels.
The OLT according to claim 11, wherein the first determining unit is configured to: calculate a difference between the first clock cycle and the second clock cycle, and an operating clock of the ONU The quotient determines the difference in transmission time.
A transmission delay difference detection system between uplink channels, comprising:

An optical network unit ONU and an optical line terminal OLT according to any one of claims 7 to 12.