Optical network data transmission method as well as system and equipment thereof

[0058] Example 1

[0059] When the backbone fiber of the main OLT in the PON network fails (or the main OLT fails), the PON network needs to perform a main-standby switchover to switch data to the standby OLT. This embodiment is based on figure 2 The schematic diagram of the active/standby switch provided is taken as an example. During the switchover of the active and standby OLTs, due to the difference in the length of the active and standby backbone fibers, the standby OLT is the new active OLT. The ONU performs re-ranging processing. In order to reduce the ranging time required for performing ranging processing on all the connected ONUs and reduce the service interruption time, an embodiment of the present invention provides a method for transmitting data on an optical network. See image 3 In this embodiment, the main-use OLT's backbone fiber fails and needs to be switched as an example for description. The content of the method is as follows:

[0060] 101: The active OLT detects the loss of signal LOS (Lost Of Signal) alarm and triggers the switchover of the active and standby OLTs; the original active OLT is transformed into a standby OLT, and the original standby OLT is transformed into a new active OLT (the following is convenient for description, in business Before the transmission resumes, the new active OLT is still called the standby OLT). Each ONU detects a LOS alarm and enters the POPUP state.

[0061] Among them, when the main optical fiber of the main OLT fails, the main OLT and each ONU will detect the signal loss LOS alarm because the main OLT and each ONU cannot receive the signal from each other. The main OLT detects the LOS alarm and learns that the main main optical fiber is faulty. , Need to switch between the active and standby OLTs: switch the data flow of the connected ONU to the standby OLT, and use the standby backbone fiber provided by the standby OLT to communicate with each ONU; when each ONU device detects a LOS alarm, the normal working The OPERATION state switches to the suspended POPUP state. At this time, the service transmission of the standby OLT and each ONU is in an interrupted state.

[0062] 102: The active OLT sends the saved parameters of each ONU to the standby OLT through the communication link, and the standby OLT obtains the parameters of each ONU.

[0063] Wherein, in this step 102, the standby OLT obtains each ONU parameter, which may occur after step 101, or at any time before step 101 (for example, when the PON system is deployed, the parameters of the connected ONUs are respectively The configuration is pre-stored in the active and standby OLTs. This embodiment of the invention does not limit the specific way and time for the standby OLT to obtain the parameters of the connected ONUs, but it must be ensured that the standby OLT has successfully obtained the access before step 106 is executed. The parameters of each ONU.

[0064] Among them, the parameters of each ONU include: the round-trip delay Rtd value of the ONU obtained by the primary OLT, the identification of each connected ONU, and the like. Among them, Rtd = ONU processing delay value + branch fiber propagation delay value + backbone fiber propagation delay value + OLT processing delay value. In order to facilitate the description, the Rtd value of the ONU obtained by the main OLT can be called the main Rtd of the ONUi, which is expressed as Rtd (main) ONUi (among them, ONUi Indicates the i-th ONU among the connected ONUs).

[0065] 103: The standby OLT selects a ranging ONU from the connected ONUs, and performs ranging on the ranging ONU.

[0066] Among them, because the number of ONUs connected to the PON network is more than one, and with the expansion of the OPN network capacity, the number of connected ONU devices will greatly increase, and the standby OLT is performing distance measurement of ONUs. When selecting, an ONU can be arbitrarily selected as the ranging ONU, and one of the connected ONUs can also be designated as the ranging ONU according to a preset rule. The embodiments of the present invention are not limited to specific methods and rules for selecting a ranging ONU.

[0067] 104: The standby OLT sends a Range Request message to the ranging ONU.

[0068] 105: After the ranging ONU receives the Range Request message, it returns a ranging response RangeResponse message to the standby OLT.

[0069] Among them, since the ranging ONU is in the POPUP state before receiving the ranging request Range Request message sent by the standby OLT, after receiving the ranging request Range Request message, it switches from the POPUP state to the RANGING ranging state.

[0070] 106: After receiving the Range Response message returned by the ranging ONU, the standby OLT obtains the round trip delay Rtd value of the ranging ONU.

[0071]Wherein, the standby OLT obtains the round trip delay Rtd value of the ranging ONU according to the receiving of the ranging response Range Response message returned by the ranging ONU and sending the ranging request Range Request message to the ranging ONU.

[0072] 107: The standby OLT obtains the main and standby backbone optical fiber propagation according to the obtained Rtd value of the ranging ONU and the round-trip delay Rtd value of the primary OLT of the ranging ONU (that is, the Rtd (primary) value of the ranging ONU device) Delay difference Δ.

[0073] Among them, the round-trip delay Rtd value of the primary OLT of the ranging ONU is specifically sent to the backup OLT through the communication link in step 101, or deployed on the backup OLT during OPN network deployment Set.

[0074] For ease of presentation, correspondingly, the Rtd value of the ranging ONU obtained by the standby OLT is expressed as Rtd (standby). As described in step 102, the Rtd value of the ONU device is specifically the processing delay value of the ONU and the branch fiber The propagation delay value, the propagation delay value of the backbone fiber, and the OLT processing delay value are composed of the Rtd on the main and backup OLT devices when the ONU is switched from the main OLT device to the backup OLT device caused by the failure of the backbone fiber. The ONU processing delay value, branch fiber propagation delay value, and OLT processing delay value in the value remain unchanged, and the only change is the backbone fiber propagation delay value caused by the difference in the length of the main and standby backbone fibers. changes happened. Therefore, the difference between the Rtd values ​​of the ONU on the active and standby OLTs is specifically the difference Δ between the main and standby backbone fiber propagation delays, namely: Rtd (main)-Rtd (standby) = Δ.

[0075] 108: The standby OLT calculates and obtains the Rtd (standby) value of each ONU device according to the acquisition of the propagation delay difference Δ of the main and standby backbone optical fibers and the prestored Rtd (primary) value of each other ONU.

[0076] Among them, the way to obtain the Rtd (primary) value of the other ONUs pre-stored on the standby OLT is the same as the way to acquire the Rtd (primary) value of the ranging ONU obtained in step 107, specifically: the primary OLT communicates The link is sent to the standby OLT, or, when the OPN network is deployed, the settings are deployed on the standby OLT.

[0077] Since the difference between the lengths of the main and backup backbone fibers is fixed, all ONUs under the primary and backup PON LT share a backbone fiber at the same time. Therefore, the propagation delay value of all ONUs in the main and backup backbone fiber sections is limited. The difference Δ is also fixed, namely:

[0078] Δ=Rtd (main) ONU1 -Rtd (standby) ONU1 = Rtd (main) ONU2 -Rtd (standby) ONU2 =......=Rtd (Main) ONUn -Rtd (standby) ONUn

[0079] Therefore, if the standby OLT obtains the difference Δ between the main and standby backbone optical fiber propagation delays of an ONU, it can use the obtained difference Δ according to the saved Rtd (primary) values ​​of other ONUs to determine the difference Δ for other ONUs. Rtd (main) is compensated, and the Rtd (standby) of other ONUs can be obtained accordingly. which is:

[0080] Rtd (standby) ONUi = Rtd (main) ONUi -Δ.

[0081] 109: The standby OLT obtains the equalization delay time EqD (standby) of each ONU according to the acquired Rtd (standby) of each ONU.

[0082] When obtaining the equalization delay time EqD (standby) of each ONU according to the obtained Rtd (standby) of each ONU, the specific reference formula is:

[0083] EqD ONUi =Teqd(Preparation)-Rtd ONUi =Teqd-(Rtd(Main) ONUi -Δ), where Teqd (standby) is a constant value, and its value can be the same as or different from Teqd (main).

[0084] 110: The standby OLT issues the acquired EqD (standby) of each ONU through the Ranging Time PLOAM message.

[0085] Among them, when the standby OLT device delivers the acquired EqD (backup) of each ONU through the Ranging Time PLOAM message, it can be delivered in the form of broadcast or unicast in the specific implementation. The embodiment of the invention does not limit the specific manner of sending the Ranging Time PLOAM message.

[0086] After each ONU receives the Ranging Time PLOAM message sent from the standby OLT, it sets the delay time according to the EqD (standby) carried therein, and triggers the entry into their respective OPERATION state to resume the transmission of the interrupted service. So far, the standby OLT has completed the ranging of all ONUs, and realized the rapid switching of the main and standby backbone fibers.

[0087] Further, in order to ensure the correctness of the transmission, the number of times the Ranging Time PLOAM message is issued by the standby OLT can also be set, such as 3 times as follows.

[0088] In particular, for the ranging ONU, the standby OLT may also obtain the Rtd value of the ranging ONU's round-trip delay in step 106, and at the same time obtain the EqD value of the ranging ONU device according to the Rtd value, and then At any time after step 106, the standby OLT can send the EqD (standby) of the ranging ONU to the ranging ONU through the Ranging Time PLOAM message, see Figure 4 The embodiment of the present invention provides a schematic diagram of information exchange of a method for sending data. As shown in the figure, the information exchange process is as follows:

[0089] 1. When the main trunk fiber fails, perform the main-standby switching operation. After detecting the LOS alarm, the standby OLT switches to the main OLT; each ONU under the main OLT switches from the normal OPEARATION state to POPUP because of the detection of the LOS alarm. Status, service transmission between OLT and ONU is interrupted.

[0090] 2. The standby OLT selects an ONU to perform the ranging process. After the ranging is completed, the ranging ONU changes from the RANGING state to the OPERATION state, and the interrupted service of the ranging ONU resumes.

[0091] 3. The standby OLT obtains the propagation delay difference Δ of the main and standby backbone optical fibers according to the ranging processing of the ranging ONU. According to the obtained Δ value and the Rtd(n) value on the primary OLT, the EqD(n) value of the remaining ONUs on the standby OLT is calculated.

[0092] 4. The standby OLT sets a new EqD(n) to other ONUs, and accordingly, the ONU changes from the POPUP state to the OPERATION state, interrupting the service to resume.

[0093] As shown in the above interaction Figure 4 As shown, the ONU can be set to be in the POPUP state, and if the Rangingrequest message of the OLT is received, the POPUP state is converted to the RANGING state, and the ranging process is started. Set the ONU in the POPUP state. If a Ranging time PLOAM message that the OLT sets the ONU EqD value is received, the ONU sets a new EqD value according to the message, that is, changes from the POPUP state to the normal OPERATION state and resumes the interrupted service transmission.

[0094] In the above embodiment of the present invention, the number of ranging ONUs acquired by the standby OLT is taken as an example for description. In particular, in specific implementation, the PON network can determine what to do on the premise of meeting service delay requirements as needed. In order to find the number of ONUs, the ranging ONUs are processed in sequence, and then the average value of the difference Δ is obtained according to the obtained main and standby Rtd difference Δ of each ranging ONU, thereby ensuring the accuracy of the calculation.

[0095] In the above embodiment of the present invention, the main-backup fiber failure triggers the main-backup switchover in the PON network as an example. Similarly, due to the main-backup switchover of the PON network triggered by the main OLT failure, the processing method is similar and will not be repeated anymore. Go into details.

[0096] In summary, in the method for transmitting data on the optical network provided by the embodiment of the present invention, when the main and standby OLTs are switched due to the failure of the backbone fiber in the PON network, the standby OLT does not need to re-range all ONUs, only ranging The Rtd value of one of the ONUs, according to the Rtd value of the ONU on the main OLT, the difference Δ between the main and standby Rtd can be obtained. For other ONUs connected, it is no longer necessary to perform ranging processing. According to the obtained difference Δ and The Rtd values ​​of other ONUs on the original active OLT can be calculated to calculate the EqD values ​​of the standby OLTs corresponding to other ONUs. Since only one ranging process is required, the service transmission can be resumed, which greatly saves the need to perform measurement on all ONUs. The time it takes to meet the time delay requirements of PON network bearer services.

[0097] Example 2

[0098] In the PON network, due to the main and standby OLT switching caused by the failure of the backbone fiber, each ONU needs to obtain a new EqD value due to the difference in parameters such as the length of the main and backup backbone fibers, see Figure 5 , The embodiment of the present invention provides a system for transmitting data on an optical network, the system includes: a transmitting device, a ranging device, and a non-ranging device, where:

[0099] The sending device is used to obtain the first round-trip delay Rtd value of the ranging device and the non-ranging device; it is also used to send a ranging request to the ranging device, and obtain the second value of the ranging device according to the ranging response of the ranging device. Round trip delay Rtd value; according to the first Rtd value and second Rtd value of the ranging device, obtain the change value of the Rtd value; when the change value is obtained, obtain the change value according to the change value and the first Rtd value of the non-ranging device The second Rtd value of the non-ranging device; obtain and send the equalized delay EqD value of the ranging device and the non-ranging device according to the acquired second Rtd value of the ranging device and the second Rtd value of the non-ranging device respectively;

[0100] The ranging device is used to receive the ranging request sent by the sending device and return a ranging response to the sending device; it is also used to receive the equalization delay EqD value sent by the sending device.

[0101] Non-ranging device, used to receive the equalization delay EqD value sent by the sending device.

[0102] Wherein, the sending device is also used to obtain the second round-trip delay Rtd value of the ranging device multiple times, and obtain the second round-trip delay Rtd value of the ranging device by averaging the multiple Rtd values. The ranging device is one or more A.

[0103] Among them, there are multiple ranging devices, and correspondingly, the sending devices include:

[0104] An obtaining module, which is used to obtain the first round-trip delay Rtd value of the ranging device and the non-ranging device;

[0105] The ranging module is used to sequentially obtain the second round-trip delay Rtd values ​​of multiple ranging devices;

[0106] The difference module is used to obtain the respective first Rtd value and the second Rtd value of the ranging device according to the second Rtd value of the ranging device obtained by the ranging module and the respective first Rtd value of the ranging device obtained by the obtaining module. The difference of the Rtd value; take the average of multiple differences to obtain the change value of the Rtd value;

[0107] The processing module is configured to obtain the second Rtd value of the non-range-finding device according to the change value obtained by the difference module and the first Rtd value of the non-range-finding device obtained by the obtaining module; respectively according to the obtained second Rtd value of the ranging device Value and the second Rtd value of the non-ranging device, obtain and send the equalized delay EqD value of the ranging device and the non-ranging device.

[0108] Further, the system also includes:

[0109] A providing device is used to provide the sending device with the first round trip delay Rtd value of the ranging device and the non-ranging device.

[0110] For detailed description, when the system provided by the embodiment of the present invention is applied in an actual optical network, refer to Figure 6 , Where the sending device is specifically embodied as a standby OLT, the ranging device is specifically embodied as a ranging ONU, and the non-ranging device is embodied as a non-ranging ONU. Correspondingly, among them,

[0111] The backup OLT is used to obtain the round-trip delay Rtd value (may be called the first Rtd value) of the main trunk fiber of the ranging ONU and the non-ranging ONU; send a ranging request to the ranging ONU, and according to the ranging ONU's measurement Get the Rtd value of the round-trip delay of the ranging ONU (that is, the second Rtd value corresponding to the backup backbone fiber); according to the Rtd value of the corresponding primary backbone fiber of the ranging ONU, obtain the Rtd value The difference Δ between the Rtd value corresponding to the backup backbone fiber of the ranging ONU and the Rtd value corresponding to the main backbone fiber (that is, the change value of the first Rtd value and the second Rtd value); according to the difference Δ and the obtained non-ranging ONU Obtain the Rtd value corresponding to the standby backbone fiber of the non-ranging ONU; then, according to the obtained Rtd value corresponding to the standby backbone fiber of the ranging device and the non-ranging device, obtain and send EqD value of equalization delay corresponding to ranging equipment and non-ranging equipment;

[0112] The ranging ONU is used to receive the ranging request sent by the backup OLT and return a ranging response to the backup OLT; and is used to receive the equalization delay EqD value sent by the backup OLT, and then use the obtained EqD value to complete its own settings.

[0113] The non-ranging ONU is used to receive the equalization delay EqD sent by the standby OLT, and then use the obtained EqD value to complete its own setting.

[0114] Among them, those skilled in the art can know that the selection of the ranging ONU can be to randomly select one or more ONUs from the multiple ONUs that are connected to be used as the ONU for ranging processing, and can also specify the access according to preset rules. One or more ONUs among the ONUs are used as ranging ONUs. The embodiments of the present invention are not limited to specific methods and rules for selecting a ranging ONU.

[0115] In particular, in the system for transmitting data on the optical network provided by the embodiment of the present invention, in specific implementation, the PON network can determine the number of ONUs as ranging ONUs on the premise that the service delay requirements are met according to the needs, and the ranging can be determined in turn. In the ranging process of the ONU, the average value of the difference Δ is obtained according to the obtained difference Δ between the main and standby Rtd values ​​of each ranging ONU, thereby ensuring the accuracy of the calculation. That is, when there are multiple ranging devices (ranging ONUs), correspondingly, the standby OLT specifically includes: an acquisition module for acquiring the first round-trip delay Rtd value of the ranging device(s) and the non-ranging device; The ranging module is used to sequentially obtain the second round-trip delay Rtd value of multiple ranging devices; the difference module is used to obtain the second Rtd value of the ranging device obtained by the ranging module and the ranging obtained by the obtaining module respectively The first Rtd value of each device, the difference between the first Rtd value and the second Rtd value of the distance measuring device is obtained; the average value of the multiple difference values ​​is taken to obtain the change value of the Rtd value; the processing module is used to obtain the change value of the Rtd value according to the difference value The change value obtained by the module and the first Rtd value of the non-ranging device obtained by the obtaining module, and the second Rtd value of the non-ranging device are obtained; respectively according to the obtained second Rtd value of the ranging device and the first Rtd value of the non-ranging device Two Rtd value, obtain and send the equalization delay EqD value of the ranging device and the non-ranging device.

[0116] Further, in the system for transmitting data on the optical network provided by the embodiment of the present invention, in specific implementation, the PON network can be used to obtain the first ranging ONU multiple times on the premise that the PON network can meet the service delay requirements as needed. Two round-trip delay Rtd values, and then take the average of multiple Rtd values ​​to obtain the second round-trip delay Rtd value of the ranging ONU. Among them, the above-mentioned ranging ONU may be one or more, thereby ensuring the accuracy of the ranging calculation accuracy.

[0117] The system for transmitting data on the optical network provided in the embodiment of the present invention may further include a providing device for providing the transmitting device with the first round-trip delay Rtd value of the ranging device and the non-ranging device.

[0118] In summary, in the system for transmitting data on the optical network provided by the embodiment of the present invention, when the main and standby OLTs are switched due to the backbone fiber failure (or the main OLT failure, etc.) in the PON network, the standby OLT does not need to retest all ONUs. It only needs to find the Rtd value of one of the ONUs. According to the Rtd value of the ONU on the active OLT, the difference Δ between the active and standby Rtd can be obtained. For other connected ONUs, it is no longer necessary to perform ranging processing. The obtained difference Δ and the Rtd value of other ONUs on the original primary OLT can be used to calculate the EqD value of the standby OLT corresponding to other ONUs. Since only one ranging process is performed, the service transmission can be resumed, greatly saving The time it takes to perform ranging on all ONUs is achieved, and the time delay requirements of PON network bearer services are met.

[0119] Example 3

[0120] See Figure 7 An embodiment of the present invention provides a device for sending data on an optical network, and the device includes:

[0121] The acquisition module is used to acquire the first round-trip delay Rtd value of the ranging device and the non-ranging device (that is, the Rtd value on the active OLT);

[0122] The ranging module is used to send a ranging request to the ranging device, and obtain the second round-trip delay Rtd value of the ranging device (that is, the Rtd value on the standby OLT) according to the ranging response of the ranging device;

[0123] The difference module is configured to obtain the change value of the Rtd value according to the first Rtd value of the ranging device obtained by the obtaining module and the second Rtd value of the ranging device obtained by the ranging module;

[0124] The processing module is configured to obtain the second Rtd value of the non-range-finding device according to the change value obtained by the difference module and the first Rtd value of the non-range-finding device obtained by the obtaining module;

[0125] The sending module is used to obtain and send the equalized delay EqD value of the ranging device and the non-ranging device according to the second Rtd value of the ranging device obtained by the ranging module and the second Rtd value of the non-ranging device obtained by the processing module .

[0126] In particular, when there are multiple ranging devices, correspondingly, the ranging module in the device for transmitting data on the optical network provided in the embodiment of the present invention is used to sequentially obtain the second round-trip delay Rtd values ​​of the multiple ranging devices;

[0127] Correspondingly,

[0128] The difference module in the device for transmitting data in the optical network provided by the embodiment of the present invention is used to obtain the respective second Rtd values ​​of the ranging device obtained by the ranging module and the respective first Rtd values ​​of the ranging device obtained by the obtaining module , Obtain the difference between the first Rtd value and the second Rtd value of the distance measuring device; take the average value of the multiple difference values ​​to obtain the change value of the Rtd value.

[0129] Further, the device for transmitting data on the optical network provided in the embodiment of the present invention, in specific implementation, on the premise that the PON network satisfies the service delay requirement, the ranging module of the device is specifically: a ranging unit for Acquire the second round-trip delay Rtd value of the ranging device multiple times, and take the average of the multiple Rtd values ​​to obtain the second round-trip delay Rtd value of the ranging device, where the above-mentioned ranging device may specifically be one or more, So as to ensure the accuracy of the ranging calculation.

[0130] Among them, the above-mentioned ranging device is embodied as a ranging ONU in actual application, and accordingly, a non-ranging device is embodied as a non-ranging ONU in actual application.

[0131] Those skilled in the art may know that, as a functional entity, the optical network transmission device provided in the embodiment of the present invention may exist alone, or may be integrated and implemented in an OLT.

[0132] In summary, in the optical network transmission equipment provided by the embodiments of the present invention, when the main and standby OLTs are switched due to the backbone fiber failure (or the main OLT failure, etc.) in the PON network, the standby OLT as the transmission equipment does not need to be used for all The ONU re-ranging only needs to find the Rtd value of one of the ONUs. According to the Rtd value of the ONU on the active OLT, the difference Δ between the active and standby Rtd can be obtained. For other connected ONUs, it is no longer necessary to perform ranging Processing, according to the obtained difference Δ and the Rtd value of other ONUs on the original primary OLT, the EqD value on the standby OLT corresponding to other ONUs can be calculated, and then the obtained EqD value can be sent in the form of broadcast or unicast In each ONU, the service transmission can be resumed by performing ranging processing only once, which greatly saves the time spent on performing ranging for all ONUs, and meets the time delay requirements of PON network bearer services.

[0133] Part of the steps in the embodiments of the present invention may be implemented by software, and the corresponding software program may be stored in a readable storage medium, such as an optical disc or a hard disk.