CN101944949B - Optical transmission control method in optical network, optical network device and system - Google Patents

Abstract

The embodiment of the present invention relates to the field of communication, and particularly discloses an optical transmission control method in an optical network, an optical network device and a system, the method including: generating a multipoint control protocol MPCP message, and the MPCP message includes the identifier of the ONU to be tested and the information of the time interval for sending the upstream optical signal allocated for the ONU under test; sending the MPCP message to the ONU under test; receiving the ONU under test and sending it within the allocated time interval the uplink optical signal; detecting the received uplink optical signal, and determining the optical power of the uplink optical signal. The invention avoids the waste of bandwidth caused by allocating bandwidth to the ONU under test through the DBA module in the optical power detection process in the prior art to detect the optical power.

Description

Optical transmission control method in optical network, optical network device and system

technical field

The invention relates to the communication field, in particular to an optical transmission control method in an optical network, an optical network device and a system.

Background technique

PON (Passive Optical Network) technology is a point-to-multipoint optical fiber access technology. PON is generally composed of OLT (Optical Line Terminal, Optical Line Terminal) on the office side, ONU (Optical Network Unit, Optical Network Unit) on the user side, and ODN (Optical Distribution Network). One PON port of the OLT can be connected to multiple ONUs.

EPON (Ethernet passive Optical Network, Ethernet passive optical network) is a kind of PON technology. It adopts PON technology in the physical layer, uses Ethernet protocol in the link layer, and realizes the connection of Ethernet by using the topology of PON. enter. Therefore, it combines the advantages of PON technology and Ethernet technology.

In the EPON system, in order to monitor and maintain the optical fiber link between the OLT and the ONU, it is necessary to obtain the performance parameters of the optical fiber link between the OLT and the ONU. In the prior art, RSSI (Received Signal Strength Indication) is used to measure the received optical power, that is, the OLT measures the power of the burst optical signal sent by the ONU to obtain the above parameters. The specific process is as follows:

The OLT performs current mirror sampling on the photocurrent corresponding to the burst optical signal sent by the ONU to obtain the mirror current of the photocurrent, then converts the mirror current into a voltage, and then samples and holds the voltage, and then uses an analog-to-digital converter (Analog-to -Digital Converter, ADC) performs analog-to-digital conversion on the sampled and held voltage to obtain a digital signal, and finally calculates the optical power. In the above process, the ONU must continuously send optical signals, so that the OLT can collect optical signals and calculate optical power.

In the course of realizing the present invention, the inventor finds that there are following problems in the prior art:

In the prior art, in order to ensure that the burst optical signal sent by the ONU reaches a certain duration, the normal service needs to be terminated, and the optical power of the ONU is measured by using an independent optical power detection device or restarting the registration or ranging process. In this way, the normal work of other ONUs will be affected.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide an optical transmission control method in an optical network, an optical network device, and a system. An optical line terminal allocates a time interval for sending an upstream optical signal to an ONU that performs optical power measurement, so that The ONU under test sends an upstream optical signal within the time interval, so as to determine the optical power of the upstream optical signal, so that the optical power can be measured without readjusting the bandwidth of each ONU in the DBA update period.

In order to solve the above technical problems, the embodiments provided by the present invention are achieved through the following technical solutions:

An embodiment of the present invention provides an optical transmission control method in an optical network, wherein an optical line terminal and an optical network unit in the optical network transmit data through an Ethernet passive optical network protocol, which is characterized in that it includes:

Allocating a first time interval for performance detection to a measured optical network unit among the plurality of optical network units registered on the optical line terminal, where the first time interval is adjacent to the second time interval for service transmission , the second time interval is an integer multiple of an update cycle for dynamic bandwidth allocation by the passive optical network;

Send the time information of the first time interval to the plurality of optical network units through the optical distribution network by using a multipoint control protocol message, the multipoint control protocol message includes the identification information of the measured optical network unit and the Information about the first time interval allocated by the optical network unit under test for performance testing;

Controlling the receiving process of the optical signal sent by the plurality of optical network units in response to the multipoint control protocol message, so that the optical line terminal detects the optical network unit under test and in the receiving interval corresponding to the first time interval The receiving interval corresponding to the second time interval receives the bearer service.

An embodiment of the present invention provides an optical line terminal OLT, including:

The Ethernet passive optical network MAC module is configured to allocate a first time interval for performance detection to a measured optical network unit among a plurality of optical network units registered on the optical line terminal, and the first time interval and The second time interval used for service transmission is adjacent, and the second time interval is an integer multiple of the update cycle for dynamic bandwidth allocation of the passive optical network, and a multipoint control protocol message is generated, and the multipoint control protocol message includes The identification information of the measured optical network unit, the information of the first time interval allocated to the measured optical network unit for performance detection, and the time interval for allocating the second time interval to the registered optical network unit for service transmission information;

An optical module, configured to carry the multipoint control protocol message in a downlink optical signal and send it to the multiple optical network units, and receive uplink optical signals sent by the multiple optical network units, the uplink optical signal includes The optical signal carrying the service sent by the optical network unit and the optical signal not carrying the service sent by the optical network unit under test, detecting the uplink optical signal sent in the receiving interval corresponding to the first time interval, and determining the measured optical signal The optical power sent by the network element.

The embodiment of the present invention provides a kind of optical network unit ONU, and this ONU comprises:

Analysis module, control module and optical module, wherein,

The parsing module is used to receive and parse the multipoint control protocol MPCP message from the optical line terminal OLT, and obtain the identifier of the ONU under test and the ONU assigned by the OLT to the ONU under test for sending for performance detection. The information of the first time interval of the upstream optical signal and the information that the OLT allocates the second time interval to the registered ONU for service transmission, the first time interval is adjacent to the second time interval for service transmission, The second time interval is an integer multiple of the update cycle for dynamic bandwidth allocation by the passive optical network;

The control module is used to judge whether the ONU identification in the MPCP message matches the ONU identification of itself, and if they match, control the optical module to send an upstream optical module that does not carry services within the first time interval. signal, and determine whether the OLT allocates the second time interval to the registered ONU for service transmission information including the information allocated to itself for service transmission, and if so, control the optical module according to the information allocated to The information of the time interval used for service transmission by itself sends the uplink optical signal carrying the service.

The embodiment of the present invention also provides a passive optical network, including an optical line terminal OLT and a plurality of optical network units ONU, wherein the OLT is connected to the plurality of ONUs through an optical distribution network ODN;

The OLT is used to allocate a first time interval for performance detection to a measured optical network unit among the plurality of optical network units registered on the optical line terminal, and the first time interval and the second time interval for service transmission The two time intervals are adjacent, and the second time interval is an integer multiple of the update period of the dynamic bandwidth allocation of the passive optical network, and the time information of the first time interval is sent to the allotment through the optical distribution network by using a multi-point control protocol message. For the plurality of optical network units, the multipoint control protocol message includes the identification information of the measured optical network unit and the information of the first time interval allocated for the measured optical network unit for detection, for the measured optical network unit The multiple optical network units control the receiving process of the optical signal sent in response to the multipoint control protocol message, and measure the optical power of the measured optical network unit in the first time interval;

The ONU is used to receive and parse the MPCP message from the OLT, obtain the identification information of the ONU under test and the first time interval information for performance detection assigned to the ONU under test; determine the Whether the identity of the ONU under test in the MPCP message matches its own ONU identity; if it matches, send an uplink optical signal that does not carry a service to the OLT through the ODN within the first time interval.

It can be seen that in the embodiment of the present invention, the OLT directly allocates a time interval for sending an upstream optical signal to the ONU under test, and encapsulates the information of the identifier of the ONU under test and the time interval for sending the uplink optical signal of the ONU under test into the MPCP In the message, an MPCP message is generated, and the MPCP message is sent to the ONU under test, the ONU under test sends an uplink optical signal within the above time interval, and the OLT detects the power of the uplink optical signal sent by the ONU under test within the above time interval. From this it can be found that the embodiment of the present invention does not need to readjust the bandwidth of each ONU in each frame in the DBA update cycle, but the OLT directly assigns a time interval for sending an upstream burst optical signal to the ONU under test, and the ONU under test can In the time interval allocated by the OLT, a relatively large bandwidth is occupied, and in the update period of the DBA, each ONU transmits data according to the bandwidth originally allocated by the DBA module, so the waste of bandwidth can be avoided, and the RSSI measurement will not be performed. The normal work of the ONU is affected, the implementation is simple and flexible, and the operability is significantly enhanced.

Description of drawings

Fig. 1 shows the schematic diagram that DBA module allocates bandwidth to tested ONU;

Fig. 2 shows the flowchart of the method embodiment in the embodiment of the present invention;

Fig. 3 shows a schematic diagram of the time interval allocated in the embodiment of the present invention;

FIG. 4 shows a schematic structural diagram of an optical line terminal OLT in an embodiment of the present invention;

FIG. 5 shows a schematic structural diagram of an optical network unit ONU in an embodiment of the present invention;

Fig. 6 shows a schematic structural diagram of a system embodiment in an embodiment of the present invention.

Detailed ways

In order to make it easier for those skilled in the art to understand and realize the present invention, the embodiments of the present invention are described in conjunction with the accompanying drawings. Here, the exemplary embodiments and descriptions of the present invention are used to explain the present invention, but not to limit the present invention.

As shown in Figure 1, a DBA update cycle is m frames, and the typical value of m is 8. In this example, the update cycle is 8 frames. Under normal operation, that is, when RSSI measurement is not required, the DBA is one for the OLT. Each ONU under the PON port is allocated a bandwidth required for work. In the figure, ONU1 occupies a bandwidth of 25us in one frame (125us), so ONU1 can transmit data within this 25us time. When RSSI measurement is required, the DBA module will adjust the bandwidth of OUN2...ONUn in order to allocate a larger bandwidth to the ONU under test (ONU1 in Figure 1 is the ONU under test), that is, increase the bandwidth of ONU1 While increasing the bandwidth, reduce the bandwidth allocated for OUN2...ONUn, as shown in the schematic diagram of bandwidth during RSSI measurement in Figure 1. After the RSSI measurement is completed, the DBA module will restore the bandwidth allocated by each ONU to the normal working state, but because the DBA module will update or adjust the bandwidth occupied by each ONU in each frame every m frames. As shown in Figure 1, the update period of the DBA module is 8 frames, each frame is 125us, that is, the update period of the DBA module is 1000us, and the RSSI measurement needs to allocate a bandwidth of at least 100us to ONU1, as shown in Figure 1. During RSSI measurement, ONU1 occupies at least 100us in each frame within an update period (8 frames) of DBA; in practice, it only takes 100us to measure optical power once, that is to say, within an update period of DBA The bandwidth allocated in the first frame of the cycle can meet the needs of the measurement, while the other 7 frames do not perform optical power measurement, but are only used for normal data transmission, and ONU1 only needs 25us of bandwidth for normal data transmission, then in DBA In an update cycle of ONU1, at least 75us×7=525us of bandwidth will be wasted by ONU1. In a DBA update cycle, the proportion of wasted bandwidth is 525us/(125us×8)=52.5%. At the same time, for other For the ONU that performs RSSI measurement, the originally required bandwidth cannot be guaranteed.

The optical power measurement method provided by the embodiment of the present invention is applied to an Ethernet passive optical network (EPON) of point-to-multipoint communication including an OLT and a plurality of ONUs, and an RSSI measurement time is allocated to an ONU that needs to perform RSSI measurement through the OLT , without adjusting the normal operating bandwidth of the ONU under one PON port of the OLT, to achieve the measurement of the received optical power, thereby providing a basis for analyzing the link performance between the OLT and the ONU.

A flow chart of a method for measuring optical power in an embodiment of the present invention is shown in Figure 2. The method includes:

S101: The MAC chip of the OLT allocates a first time interval T1 for performance detection to a measured optical network unit among a plurality of optical network units registered on the optical line terminal. Wherein, the first time interval T1 is adjacent to the second time interval T2 used for service transmission, and the second time interval T2 is an integer multiple of an update cycle for dynamic bandwidth allocation by the passive optical network.

When the CPU of the OLT initiates to measure the received optical power of the ONU on the ONU side (that is, the ONU under test), it sends an order to the MAC chip of the OLT to measure the received optical power. The mark of measured ONU), the MAC chip of OLT distributes the first time interval T1 that is used for RSSI measurement for measured optical network unit, the first time interval T1 in the embodiment of the present invention is the second of the integral multiple of the update cycle of DBA A time interval adjacent to the time interval T2 is specifically shown in Figure 3. In Figure 3, there are m frames in one update period of the DBA, and the allocated first time interval T1 is the RSSI measurement time in Figure 3. The first time interval T1 is independent from the second time interval T2 and adjacent to the second time interval T2. Optionally, in order to ensure that the measurement and the service are not affected, the time interval g1 between the starting point of the first time interval T1 and the end point of the second interval T2 before the first time interval T1 can be set (not shown in the figure ), and the time interval g2 (not shown in the figure) between the end point of the first time interval T1 and the start point of the second time interval T2 after the first time interval T1 is called the measurement guard interval, wherein the time interval g1 and g2 may be the same or different. Therefore, the MAC chip of the OLT does not need to readjust the bandwidth of each ONU in each frame in the DBA update cycle when allocating the above time interval for the ONU under test, reducing the impact on the bandwidth of other services. Wherein, the second time may be a DBA update period, or a multiple of the DBA update period. In EPON, the frame length of the Ethernet protocol is a variable frame length. Therefore, in the embodiment of the present invention, there is no limit to the length of the first time interval T1, as long as the accuracy requirement for measuring optical power can be met. Further, the time length of the first time interval T1 is preferably not to affect the normal service transmission of other ONUs.

Further, the above information of the time interval may include start time information of the time interval, end time information of the time interval and length information of the time interval, or any two of them.

S102: Using an MPCP (Multi-Point Control Protocol, multi-point control protocol) message to send the information of the first time interval T1 allocated to the measured optical network unit to multiple optical network units through the optical distribution network. Wherein, the MPCP message includes the identification information of the optical network unit under test and the information of the first time interval T1 allocated to the optical network unit under test for performance detection.

The OLT generates a burst optical power measurement command, which contains the identifier of the ONU under test, and according to the identifier of the ONU under test in the burst optical power measurement command, assigns the ONU under test for sending upstream optical signals the first time interval, and encapsulate the information of the ONU under test and the time interval allocated for the ONU under test into an MPCP message, thereby generating an MPCP message sent to the ONU under test.

As mentioned above, the downlink MPCP message of EPON carries the identification information of the ONU under test and the information of the first time interval T1. The OLT sends the above MPCP message to multiple ONUs, and the ONU under test receives the downlink MPCP message sent by the OLT. After the message, analyze the MPCP message from the downlink frame MPCP message, and obtain the identifier of the ONU under test and the information of the first time interval T1 for sending the upstream optical signal that the OLT distributes for the ONU under test from the MPCP message; then , the ONU under test compares the ONU identification in the MPCP message with its own ONU identification, and if it does not match, it remains silent in the first time interval T1 allocated by the OLT for sending upstream optical signals for the ONU under test; if match, then send the upstream optical signal within the time interval T1 allocated by the OLT for sending the upstream optical signal to the ONU under test. After the uplink optical signal, the start of the receiving interval can be determined and the power of the uplink optical signal can be detected.

S103: Control the receiving process of the optical signal sent by multiple ONUs in response to the MPC message, so that the optical power of the ONU under test is detected in the receiving interval corresponding to the first time interval T1.

Since multiple ONUs connected to the OLT do not interrupt the service, for the OLT, it continues to receive the upstream optical signals sent by multiple ONUs, including the optical signals sent by the normal ONUs and the optical signals sent by the ONU under test. The OLT controls the receiving process of the uplink optical signal, detects the optical power of the received optical signal in the receiving interval corresponding to the first time interval T1 to obtain the optical power sent by the ONU under test, and receives the optical power corresponding to the second time interval T2 The interval receives the carried services. The OLT receives the upstream optical signal sent by the ONU under test, and detects the ONU identifier carried in the upstream optical signal, and when it detects that the ONU identifier in the upstream optical signal matches the ONU identifier stored in the OLT, determine the start of the receiving time , and determine the length of the receiving interval according to the information of the time interval for sending the upstream optical signal assigned by the OLT to the ONU under test. That is, the receiving interval is the same as the time interval, the uplink optical signal sent by the ONU under test is detected in the receiving interval, and the optical power sent by the ONU under test is determined. Among them, the method of determining the optical power sent by the ONU under test according to the upstream optical signal sent by the ONU is: the MAC chip of the OLT sends the command RSSI-Trig for RSSI measurement, controls the optical module to sample the optical signal, and performs A/D on the sampling result. (analog signal to digital signal) conversion to obtain the value of optical power. After detecting the optical power of the upstream optical signal sent by the ONU under test, the performance of the link between the OLT and the ONU under test can be analyzed according to the detected optical power value.

Specifically, the OLT may adjust the time length of the second time interval and/or the first time interval to meet the requirements of the system performance detection. Since the second time interval in the embodiment of the present invention is an integer multiple of the DBA update cycle, the OLT can adjust the time length of the second time interval by adjusting the multiple of the DBA update cycle. If the system has high requirements for real-time detection, the DBA can be reduced. The multiple of the update cycle is used to increase the performance detection frequency to ensure real-time requirements; if the system requires high detection accuracy for each ONU new energy, the length of the second time interval can be increased to ensure the accuracy requirements. On the other hand, the OLT can also control the performance detection frequency by adjusting whether the first time interval exists, and at the same time ensure the bandwidth utilization rate. For example, the OLT judges the system performance by statistically detecting the optical power value. The first time interval is not allocated for a period of time, that is, the time length value of the first time interval is set to 0. The DBA update period here is set according to the needs of the system, usually the time length of m frames, m is a positive integer, the preferred value is 1, 2, 4, 8, 16; each frame is provided to one or more ONUs Send uplink data. In the following, the second time intervals used for service transmission are of equal length, that is, T1, T2...Tn are equal in length, and are unified as T (Tn represents the nth second time interval, not shown in the figure) as an example to illustrate, The DBA update period of the system is 4 frames, and the initial value of T is set to twice the DBA update period. The OLT allocates the first time interval for performance detection to the tested ONU among the registered multiple ONUs according to the cycle T. The time length of the first time interval assigned by a tested ONU can be set according to needs, of course, a unified time length of the first time interval can be assigned to multiple ONUs to simplify control; the OLT receives upstream optical signals from multiple ONUs The receiving process is controlled, and the optical power in the receiving interval corresponding to the first time interval is obtained from the optical module as the optical power sent by the ONU under test. The OLT analyzes the link performance between the OLT and the ONU under test based on the optical power sent by the ONU under test. The OLT can also determine the performance of the PON system by statistically detecting the optical power value of the tested ONU. If the performance is good, the value of T can be adjusted, such as increasing the DBA update cycle from 2 times to 4 times. The OLT can also not adjust the value of T. And only the sign is assigned the value of the first time interval, for example, the value of the first interval is set to 0 within a period of time. The OLT can also be configured such that the second time interval for service transmission is variable, that is, T1, T2...Tn becomes longer (Tn represents the nth second time interval, not shown in the figure), and the first time interval The setting of T1 can be variable length or equal length. That is, T1 can be set to different values according to needs.

In one embodiment of the present invention, the optical module that receives the optical signal sent by the ONU that normally conducts business provides the optical power detection of the ONU under test, and the optical module can be connected to the analysis and processing module that provides performance analysis, and the analysis and processing module can According to the detected optical power value, analyze the link between the OLT and the ONU under test.

In this embodiment, the OLT directly assigns a time interval for sending an uplink optical signal to the ONU under test, and encapsulates the information of the identifier of the ONU under test and the time interval for sending the uplink optical signal of the ONU under test into an MPCP message to generate an MPCP message, And send the MPCP message to the ONU under test, the ONU under test sends an uplink optical signal within the above time interval, and the OLT detects the power of the uplink optical signal sent by the ONU under test within the above time interval. From this it can be found that the present embodiment does not need to readjust the bandwidth of each ONU in each frame in the DBA update cycle, but the OLT directly assigns a time interval for sending an upstream burst optical signal to the ONU under test, and the ONU under test can be in The time interval allocated by the OLT occupies a relatively large bandwidth, and in the update cycle of the DBA, each ONU transmits data according to the bandwidth originally allocated by the DBA module, so that the waste of bandwidth can be avoided, and the ONU that does not perform RSSI measurement will not be affected. It is simple and flexible to implement, and the operability is significantly enhanced.

An embodiment of the present invention provides an optical line terminal 40. The structure schematic diagram of the OLT is shown in FIG. 4, including:

EMAC (EPON MAC, Ethernet passive optical network MAC) module 42, is used for generating multi-point control protocol MPCP message, carries the identification information of tested ONU and is described tested ONU in the described multi-point control protocol MPCP message Information about the allocated first time interval for sending uplink optical signals, the first time interval is adjacent to the second time interval used for service transmission, and the second time interval is the update period for dynamic bandwidth allocation of the passive optical network Integer multiples of . Wherein, the EMAC module 42 also has the function of adjusting the time length of the first time interval and/or the second time interval, and the specific implementation is referred to above.

The optical module 43 is used to send the multipoint control protocol MPCP message generated by the EMAC module 42 to the ONU under test, and receive the upstream optical signal sent by the ONU under test within the time interval, and detect the ONU under test Whether the identification information of the ONU carried in the upstream optical signal matches the identification of the ONU under test, and determine the start of the receiving interval after matching, and according to the information of the time interval for sending the upstream optical signal allocated by the OLT to the ONU under test , determining the length of the receiving interval, detecting and receiving the upstream optical signal sent by the ONU under test in the receiving interval, and determining the optical power of the upstream optical signal. Wherein, the process of determining the optical power of the uplink optical signal according to the received uplink optical signal is the same as that in the prior art.

The above optical line terminal OLT40 may further include:

An adjustment module (not shown in the figure), configured to control the existence of the first time interval and/or the length of the second time interval to adjust the frequency of performance detection. Specifically, the adjustment module may control the existence of the first time interval and/or the length of the second time interval according to the detected performance of the PON system or the requirements of the PON system or external commands to adjust the frequency of performance detection. Spend. The adjustment module may be built in the EMAC module 23 or independent of the EMAC module 23 .

The processor CPU41 is configured to initiate the measurement of the optical power of the ONU under test at the ONU side, and send the identification of the ONU to be measured (ie, the ONU under test) to the EMAC module 42 .

Wherein, the EMAC module 42 specifically includes: an optical power measurement command module 421 , a DBA module 422 , an MPCP module 423 and a control module 424 . in,

Optical power measurement command module 421, for according to the identification of described ONU under test, produces the optical power measurement order that comprises described ONU identification under test, and sends this optical power measurement order to described DBA module 422 and MPCP module 423.

The DBA module 422 is used to receive the measurement command sent by the optical power measurement command module 421, and allocate a time interval for the ONU under test according to the identification information of the ONU under test in the measurement command, and send the time interval to the MPCP module 423. In the prior art, the DBA module 422 is used for dynamic bandwidth allocation and adjustment to update the bandwidth occupied by each ONU in each frame in the DBA update cycle, so as to allocate a relatively large bandwidth to the ONU under test, so that the ONU under test The ONU can send an uplink optical signal with a longer duration within the large bandwidth for the OLT to measure the burst optical power. In this embodiment, the DBA module 422 directly assigns a time interval for sending an uplink optical signal to the ONU under test, without the need for the DBA module 422 to perform dynamic bandwidth adjustment to update the bandwidth occupied by each ONU, thereby assigning a time interval for the ONU under test. Large bandwidth, so there will be no waste of bandwidth.

The MPCP module 423 is used to receive the identification information of the ONU under test sent by the optical power measurement command module 421, and the time interval information allocated by the DBA module 422 for the ONU under test, and the ONU under test and the ONU under test The information of the time interval is encapsulated into an MPCP message, thereby generating an MPCP message sent to the ONU under test.

The control module 424 is configured to generate a control command to the optical module 43, and the control command is used to control the optical module 43 to measure the optical power.

The optical module 44 is also used to report the determined optical power value to the CPU 41 after determining the optical power of the uplink optical signal, and the CPU 41 analyzes the link performance between the ONU under test and the OLT according to the received optical power value, For example, analyze the optical fiber link loss between the tested ONU and the OLT, the relationship between the optical fiber link loss between the tested ONU and the OLT over time, etc.

An embodiment of the present invention provides an optical network unit 50. A schematic structural diagram of the network unit 50 is shown in FIG. 5, including:

Analysis module 51, control module 52 and optical module 53;

Parsing module 51 is used for receiving and parsing the multi-point control protocol MPCP message from OLT, obtains the identification information of tested ONU and the information of the first time interval that OLT distributes to tested ONU for performance detection and OLT will Information about the second time interval allocated to the registered ONU for service transmission. The information that the OLT allocates the second time interval to the registered ONU for service transmission may be information about the time interval for service transmission allocated to the corresponding ONU, or may be the amount of data allocated to the corresponding ONU and the time interval of the ONU. Loopback delay.

Control module 52, is used for judging whether the mark of ONU in the described MPCP message matches with the ONU mark of being tested, if match, then control optical module 53 in the first time interval that OLT distributes to the ONU to be tested for performance detection If it matches, control the optical module 53 to send an uplink optical signal that does not carry a service within the first time interval for performance detection allocated by the OLT to the ONU under test, and judge that the OLT will use the second time interval Whether there is information for service transmission allocated to the registered optical network unit in the interval, and if so, control the optical module 53 to send the bearer service according to the information for service transmission allocated to itself uplink optical signal. Wherein, the upstream optical signal that does not carry services carries the identification of the ONU (that is, the ONU under test) 50, so that after the OLT receives the upstream optical signal, it can determine the upstream optical signal through the identification information in the upstream optical signal. It is the upstream optical signal sent by the ONU under test, and then the start of the receiving interval is determined, and the power of the upstream optical signal is received and detected. It is worth noting that the uplink optical signal that does not carry traffic may not carry the identity of the ONU (that is, the ONU under test) 50. In this case, the OLT schedules and determines which ONU under test the received optical signal is from .

The embodiment of the present invention provides a passive optical network. The structural diagram of the system is shown in FIG. 6, including: an optical line terminal OLT61 and an optical network unit ONU63. The structure of the optical network unit is shown in Figure 4, and the structure of the optical network unit is shown in Figure 5.

The OLT61 is connected to a plurality of ONU63 through the optical distribution network ODN62, wherein the OLT61 is connected to one end of the ODN62, and the other end of the ODN62 is connected to a plurality of optical network units. Taking ONU-1 as an example below, how the OLT realizes the measurement of the burst optical power of the ONU in this network is described in detail.

It is assumed that OLT61 initiates the measurement of the burst optical power of ONU-1 to analyze the performance of the optical fiber link between OLT61 and ONU-1.

The OLT61 sends one or more MPCP messages to the registered ONUs in a broadcast manner, wherein ONU-1 is assigned a first time interval for performance detection, and the ONU-1 identifier and the above-mentioned performance detection time interval are used The information of the first time interval is encapsulated into the MPCP message, and the information of distributing the second time interval to the registered ONU for service transmission is also encapsulated into the MPCP message, and then the OLT sends the MPCP message through the ODN to the ODN62 connected to the ODN On the ONU. Wherein, the generation process of the MPCP message is the same as the method embodiment, and will not be described in detail here. The information that the OLT allocates the second time interval to the registered ONU for service transmission may be information about the time interval for service transmission allocated to the corresponding ONU, or may be the amount of data allocated to the corresponding ONU and the time interval of the ONU. Loopback delay.

All the ONUs connected to ODN62 in Figure 6 can receive the MPCP message sent by the OLT. Wherein, each ONU receives and parses the above-mentioned information including the identification of ONU-1 and the first time interval allocated by the OLT to ONU-1 for performance testing, and the OLT assigns the second time interval to the registered ONU for business One or more MPCP messages of the transmitted information, obtain the identification of ONU-1 and the information of the first time interval for performance detection that OLT61 distributes to ONU-1, and compare the identification of ONU-1 with its own identification; If it does not match, for example, other ONUs except ONU-1 do not match, these ONUs will remain silent within the time interval allocated by OLT61 to ONU-1, that is, they will not send any upstream optical signals to OLT61; if they match, ONU- 1. When it is found that the identity of the ONU under test matches the identity of its own ONU, ONU-1 sends an upstream optical signal that does not carry services within the first time interval allocated by the OLT to ONU-1. Further, ONU-1 will also judge whether the information that the OLT allocates the second time interval to the registered ONU for service transmission includes the information for service transmission allocated to itself, and if so, according to the user allocated to itself Send the uplink optical signal carrying the service based on the service transmission information. For other ONUs except ONU-1, keep silent in the first time interval, if it is judged that the information that the OLT allocates the second time interval to the registered ONU for service transmission contains the information assigned to itself for service transmission, then Send the uplink optical signal bearing the service according to the information allocated to itself for service transmission.

The upstream optical signal sent by ONU-1 is sent to OLT 61 through optical distribution network 62 .

OLT61 receives the upstream optical signal sent by ONU-1, and determines the power of the upstream optical signal, and then, OLT61 analyzes the performance of the optical fiber link between ONU-1 and OLT62 according to the detected power of the upstream optical signal. Wherein, the method for the OLT61 to determine the power of the upstream optical signal according to the upstream optical signal sent by the ONU specifically includes: the OLT receives the upstream optical signal sent by the ONU under test that does not carry services, and detects the ONU identifier carried in the upstream optical signal. When it is detected that the identifier of the ONU in the upstream optical signal matches the identifier of the ONU stored in the OLT, determine the start of the receiving time, and determine the first time interval for performance detection assigned by the OLT to the ONU under test. The length of the receive interval. That is, the receiving interval is the same as the time interval, and the upstream optical signal sent by the ONU under test is detected in the receiving interval; then, the optical power of the upstream optical signal is determined according to the detected upstream optical signal. Among them, the specific method of determining the optical power of the optical signal according to the upstream optical signal reported by the ONU is: the MAC chip of the OLT sends the RSSI measurement command RSSI-Trig, controls the optical module to perform optical signal sampling, and performs A/D (simulation) on the sampling result. signal to digital signal) to obtain the value of optical power.

Through the above description of the embodiment of the present invention, it can be seen that the test process of the embodiment of the present invention can avoid the waste of bandwidth and will not affect the normal operation of each ONU. It is simple and flexible to implement and highly operable.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing related hardware through computer programs, and the programs can be stored in a computer-readable storage medium. When the program is executed, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM) or a random access memory (Random Access Memory, RAM), etc.

The method, system and device for measuring optical power provided by the embodiments of the present invention have been described above in detail. In this paper, specific examples are used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for To help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. In summary, the content of this specification It should not be construed as a limitation of the invention.

Claims (11)

1. An optical transmission control method in an optical network, in which an optical line terminal and an optical network unit transmit data through an ethernet passive optical network protocol, comprising:

allocating a first time interval for performance detection to a tested optical network unit in a plurality of optical network units registered on an optical line terminal, wherein the first time interval is adjacent to a second time interval for service transmission of the plurality of optical network units registered, and the second time interval is an integral multiple of an update cycle of dynamic bandwidth allocation of a passive optical network;

sending time information of a first time interval to the plurality of optical network units through an optical distribution network by using a multipoint control protocol message, wherein the multipoint control protocol message comprises identification information of the tested optical network unit and information of the first time interval which is distributed for the tested optical network unit and used for performance detection;

and controlling the receiving process of the optical signals sent by the plurality of optical network units in response to the multipoint control protocol message, so that the optical line terminal detects the optical power of the measured optical network unit in the receiving interval corresponding to the first time interval.

2. The method according to claim 1, wherein before allocating the first time interval for performance detection to the tested optical network unit among the plurality of optical network units registered on the optical line terminal, the method further comprises:

and receiving a command for measuring the optical power, wherein the command comprises the identification information of the measured optical network unit.

3. The method according to claim 1 or 2,

and controlling the existence of the first time interval and/or the time length of the second time interval to adjust the frequency of performance detection.

4. An optical line termination, OLT, comprising:

an ethernet passive optical network MAC module, configured to allocate a first time interval for performance detection to a tested optical network unit among a plurality of optical network units registered on an optical line terminal, where the first time interval is adjacent to a second time interval for service transmission, and the second time interval is an integer multiple of an update period of dynamic bandwidth allocation performed by a passive optical network, and generates a multipoint control protocol message, where the multipoint control protocol message includes identification information of the tested optical network unit, information of the first time interval for performance detection allocated to the tested optical network unit, and information of allocating the second time interval to the registered optical network unit for service transmission;

and the optical module is configured to bear the multipoint control protocol message in a downlink optical signal, send the multipoint control protocol message to the plurality of optical network units, receive an uplink optical signal sent by the plurality of optical network units, detect the uplink optical signal sent in a receiving interval corresponding to the first time interval, and determine optical power sent by the measured optical network unit, where the uplink optical signal includes an optical signal that is sent by an optical network unit and carries a service and an optical signal that is sent by a measured optical network unit and does not carry a service.

5. The OLT of claim 4, further comprising: and the adjusting module is used for controlling the existence of the first time interval and/or the time length of the second time interval so as to adjust the frequency of performance detection.

6. The OLT of claim 4, wherein the Ethernet passive optical network (MAC) module specifically comprises: an optical power measurement command module, a dynamic bandwidth allocation DBA module, a multi-point control protocol MPCP module and a control module, wherein

The optical power measurement command module is configured to generate an optical power measurement command including an identifier of a measured optical network unit according to the identifier of the measured optical network unit, and send the optical power measurement command to the DBA module and the MPCP module;

the DBA module is configured to receive the optical power measurement command sent by the optical power measurement command module, allocate the first time interval to the measured ONU according to the identification information of the measured optical network unit in the optical power measurement command, and send the time interval to the MPCP module;

the MPCP module is used for packaging the identification information of the ONU to be tested and the time interval information distributed to the ONU to be tested by the DBA module into MPCP information to generate MPCP information;

the control module is used for generating a control command to the optical module, and the control command is used for controlling the optical module to measure the optical power.

7. The OLT of claim 6, wherein the Ethernet passive optical network (MAC) module further comprises: and the adjusting module is used for controlling the existence of the first time interval and/or the time length of the second time interval so as to adjust the frequency of performance detection.

8. The OLT of claim 6 or claim 7, further comprising:

and the processor is used for initiating the measurement of the optical power of the measured optical network unit and sending the identifier of the measured optical network unit to the Ethernet passive optical network MAC module.

9. An optical network unit, ONU, comprising:

an analysis module, a control module and a light module, wherein,

the analysis module is configured to receive and analyze a multi-point control protocol MPCP message from an optical line terminal OLT, to obtain an identifier of a measured ONU, information of a first time interval, which is allocated to the measured ONU by the OLT and used to send an uplink optical signal for performance detection, and information, which is allocated to a registered ONU by the OLT and used for service transmission, of a second time interval, where the first time interval and the second time interval are adjacent to each other, and the second time interval is an integer multiple of an update period of dynamic bandwidth allocation performed by a passive optical network;

the control module is configured to determine whether an identifier of the ONU in the MPCP message matches an identifier of the ONU itself, and if the identifier of the ONU matches the identifier of the ONU itself, control the optical module to send an uplink optical signal that does not carry a service in the first time interval, and determine whether information that the OLT allocates the second time interval to the registered ONU for service transmission contains information that is allocated to the ONU itself for service transmission, and if the information does, control the optical module to send the uplink optical signal that carries a service according to the information that is allocated to the ONU itself for service transmission.

10. A passive optical network is characterized by comprising an Optical Line Terminal (OLT) and a plurality of Optical Network Units (ONU), wherein the OLT is connected to the ONU through an Optical Distribution Network (ODN);

the OLT is used for allocating a first time interval for performance detection to a tested optical network unit in a plurality of optical network units registered on the OLT, the first time interval and a second time interval for registered traffic transmission of the plurality of optical network units are adjacent, the second time interval is integral multiple of the update period of the passive optical network for dynamic bandwidth allocation, and transmitting time information of the first time interval to the plurality of optical network units through the optical distribution network by using a multicast control protocol message, the multipoint control protocol message comprises the identification information of the tested optical network unit and the information of the first time interval allocated for the tested optical network unit for detection, controlling the receiving process of the optical signals sent by the plurality of optical network units in response to the multipoint control protocol message, and measuring the optical power of the detected optical network unit in the first time interval;

the ONU is used for receiving and analyzing the multipoint control protocol message from the OLT to obtain the identification information of the tested ONU and the first time interval information which is distributed for the tested ONU and is used for performance detection; determining whether the identification of the detected ONU in the multipoint control protocol message is matched with the identification of the ONU per se; and if so, sending an uplink optical signal which does not carry service to the OLT through the ODN in the first time interval.

11. The pon of claim 10, wherein the controlling the receiving process of the optical signals sent by the onu in response to the mp protocol message comprises: and detecting the identification of the ONU carried in the received uplink optical signal, determining the start of a receiving interval when detecting that the identification of the ONU carried in the uplink optical signal is matched with the identification of the ONU to be detected, and taking the time length of the first time interval as the time length of the receiving interval.