CN101615927A - A kind of reverse method of multi-plexing light accessing system, device and system - Google Patents
A kind of reverse method of multi-plexing light accessing system, device and system Download PDFInfo
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Abstract
Embodiments of the invention disclose a kind of reverse method, device and system of multi-plexing light accessing system, the local side of described multi-plexing light accessing system comprises first interface and second interface, first interface is couple to operating path, second interface is couple to backup path, and described method comprises: obtain from first interface and send descending frame head and receive time of two time points of up frame head and/or the time difference between two time points from second interface; According to the time difference between time of described two time points and/or two time points, obtain the adjustment time that sends descending frame head from second interface; According to the time of described adjustment time adjustment, carry out from first interface switching to second interface from described second interface transmission descending frame head.Embodiments of the invention can be adjusted the descending frame head of spare interface by in the process normal, have avoided ONU to enter and have re-registered and distance measuring states, have saved a large amount of switching times, and ONU does not roll off the production line simultaneously, to almost not influence of business.
Description
Technical Field
The present invention relates to the field of communications technologies, and in particular, to a switching method, device, and system for an optical access system.
Background
A Passive Optical Network (PON) system is a system that provides an Optical access solution for subscribers. The PON system includes an Optical Line Termination (OLT) disposed at a Central Office (CO), and an Optical Network Unit (ONU) or an Optical Network Termination (ONT) connected to a Customer Premise Network (CPN) through an Optical Distribution Network (ODN), where passive means that the ODN mainly includes passive devices such as an Optical Splitter/combiner (Splitter), and does not require or requires only a small amount of expensive active electronic devices. In the PON system, the main signal processing functions are performed in the local side equipment OLT and the customer premises equipment ONU/ONT. In terms of the content of the bearer, the typical PON system now includes APON/bpon (atm Based PON), epon (ethernet Based PON), gpon (gigabit PON), and so on; from the wavelength transmission method, there are time Division multiplexing passive optical network TDM-PON, wavelength Division multiplexing passive optical network (WDM PON), and code Division multiplexing passive optical network CDMA-PON.
With the development and application of passive optical network technology, the requirements for system performance are higher and higher, and thus demands for protection of PON systems are raised, including device-level protection and/or line-level protection. The line-level protection relates to the protection of the main optical fiber and the standby optical fiber, and service is not influenced when one of the optical fibers fails; the equipment level protection relates to the protection of the main processing module and the standby processing module, and guarantees that the service is not influenced when one processing module fails.
When implementing protection switching, the influence of the main/standby transmission delay needs to be considered, and when switching between main/standby, the delay needs to be adjusted. The existing middle adjusting mode is as follows: and opening a ranging window, respectively ranging each user, and calculating delay according to ranging results so as to adjust by using the calculated delay. For example, for the PON port backup networking diagram shown in fig. 1: the local side OLT of the PON system includes two PON modules PON LT1 and PON LT2, which are respectively connected to optical fibers F1 and F2 of the ODN through a port 1 and a port 2 (or called as a channel 1 and a channel 2), where the PON LT1 is used as an active PON module below, the port 1 is an interface of a working path, the PON LT1 is used as an interface of a standby path, and the port 2 is used as a PON module below, and describes an active/standby switching process in the prior art, as shown in fig. 2, including the following steps:
step s201, when the main/standby interfaces need to be switched, stopping sending data from the port 1 (interface of the working path), and continuously taking off the line of the ONU; .
Step s202, registering and ranging each ONU through a port 2 (interface of the backup path), so as to obtain a Delay parameter related to the port 2, such as Equalization Delay (EQD), where the EQD is a waiting Delay performed inside the ONU to ensure that the ONUs do not have uplink collision, so that all ONUs are in the same physical distance;
step s203, after all the ONUs on line are on line again, the network dominated by the interface of the original backup path is established, and the master-backup switching is completed.
In the process of implementing the invention, the inventor finds that the prior art has at least the following disadvantages:
by adopting the mode, each online ONU needs to be off-line and then re-registered to be on-line, and the OLT can only perform the registration operation of one ONU each time and can only complete the ranging of all users for switching, thereby consuming a large amount of time, resulting in slow on-line time of the ONUs and overlong service interruption time in the process of main/standby switching; moreover, each ONU needs to re-measure the distance to determine the new EQD, so the whole switching process takes a long time. On the other hand, as the number of users increases, the ranging time is further prolonged, and the method cannot be tolerated by operators and users. Therefore, the protection structure cannot meet the requirement of protection switching time when the system fails.
Disclosure of Invention
Embodiments of the present invention provide a switching method, apparatus, and system for an optical access system, so as to simplify a switching process of a main/standby interface and shorten service interruption time in the main/standby switching process.
An embodiment of the present invention provides a switching method for an optical access system, where a local side of the optical access system includes a first interface and a second interface, the first interface is coupled to a working path, and the second interface is coupled to a standby path, including:
acquiring time of two time points for sending a downlink frame header from a first interface and receiving an uplink frame header from a second interface and/or time difference between the two time points;
acquiring the adjustment time for sending the downlink frame header from the second interface according to the time of the two time points and/or the time difference between the two time points;
and adjusting the time for sending the downlink frame header from the second interface according to the adjustment time, and executing the switching from the first interface to the second interface.
The embodiment of the invention also provides an optical line terminal, which comprises a first interface function module, a second interface function module and a control module,
the first interface function module is used for providing an interface processing function of a working path;
the second interface function module is used for providing an interface processing function of a standby path;
the control module is configured to obtain time of the first interface function module sending the downlink frame header and time difference between two time points when the second interface function module receives the uplink frame header and/or time difference between two time points, obtain adjustment time of the second interface function module sending the downlink frame header according to the time of the two time points and/or the time difference between the two time points, adjust time of sending the downlink frame header from the second interface function module according to the adjustment time, and control switching from the first interface function module to the second interface function module.
The embodiment of the present invention further provides an optical access system, where the optical access system includes an optical line terminal and an optical network terminal, a connection path between the optical line terminal and the optical network terminal includes a working path and a standby path, the optical line terminal includes a first interface and a second interface, the first interface is coupled to the working path, the second interface is coupled to the standby path,
the optical line terminal is used for acquiring time of two time points and/or time difference between the two time points when the downlink frame header is sent from the first interface and the uplink frame header is received from the second interface, and acquiring adjustment time when the downlink frame header is sent from the second interface according to the time of the two time points and/or the time difference between the two time points; and adjusting the time for sending the downlink frame header from the second interface according to the adjustment time for sending the downlink frame header from the interface of the standby path, and executing the switching from the working path to the standby path.
An embodiment of the present invention further provides a switching control device, where the switching control device includes: an adjustment time obtaining unit, an adjustment unit and a switching control unit; the switching control device also comprises a first time acquisition unit and/or a second time acquisition unit; wherein,
the first time obtaining unit is used for obtaining the time of two time points of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path;
the second time obtaining unit is used for obtaining the time between two time points of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path;
the adjustment time acquiring unit is used for calculating the adjustment time between the interface of the working path and the interface of the standby path according to the time acquired by the first time acquiring unit and/or the time difference acquired by the second time acquiring unit; the adjusting unit is used for adjusting the time for sending the downlink frame header from the interface of the standby path according to the adjusting time acquired by the adjusting time acquiring unit;
and the switching control unit is used for controlling the switching from the interface of the working path to the interface of the standby path after the adjusting unit adjusts the time for sending the downlink frame header from the interface of the standby path.
The embodiment of the invention has the following advantages:
in the normal passing process, the time of two time points of sending the downlink frame header from the first interface and receiving the uplink frame header from the second interface and/or the time difference between the two time points are/is obtained, so that the downlink frame header of the standby interface is adjusted, the ONU is prevented from entering a re-registration and ranging state, a large amount of switching time is saved, and meanwhile, the ONU is not offline and has almost no influence on the service.
Drawings
Fig. 1 is a diagram of a conventional port backup networking of a passive optical network in the prior art;
fig. 2 is a flow chart of port active/standby switching of a passive optical network OLT in the prior art;
fig. 3 is a schematic structural diagram of a switching device of a main/standby interface of an OLT device in an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a network device in an embodiment of the present invention;
FIG. 5 is a schematic diagram of a network device according to another embodiment of the present invention;
fig. 6 is a flowchart of a method for switching between main and standby interfaces of an OLT device in an embodiment of the present invention.
Detailed Description
The following describes the embodiments of the present invention with reference to the drawings and examples.
An embodiment of the present invention provides a switching control device, as shown in fig. 3, including:
a first time obtaining unit 11, configured to obtain time of two time points when a downlink frame header is sent from an interface of a working path and an uplink frame header is received from an interface of a standby path;
a second time obtaining unit 12, configured to obtain a time difference by timing between two time points (time periods) when the downlink frame header is sent from the interface of the working path to the uplink frame header is received from the interface of the standby path; if a timer is used, sending a downlink frame header from an interface of the working path to start timing, receiving an uplink frame header from an interface of the standby path to finish timing so as to record the time difference between sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path;
an adjustment time obtaining unit 13, configured to calculate an adjustment time between an interface of the working path and an interface of the standby path, for example, the adjustment time between the interface of the working path and the interface of the standby path may be calculated according to the time for sending the downlink frame header from the interface of the working path and the time for receiving the uplink frame header from the interface of the standby path, which are obtained by the first time obtaining unit, or the adjustment time between the interface of the working path and the interface of the standby path may be calculated according to the time difference between sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path, which is obtained by the second time obtaining unit 12;
a storage unit 15, configured to store at least one piece of time information acquired by the first time acquisition unit 11, the second time acquisition unit 12, and the adjustment time acquisition unit 13; interface of working path and interface of backup path
And an adjusting unit 17, configured to adjust, according to the interface time information of the interface backup path of the working path stored in the storage unit 15, a time for sending the downlink frame header by the interface of the backup path. Specifically, if the time for the interface of the standby path to receive the uplink frame header of the ONU is later than the time for the interface of the working path to receive the uplink frame header from the ONU, the time is adjusted to be T, and the downlink frame header sent from the interface of the standby path is earlier than the downlink frame header sent from the interface of the working path by T time; the time for receiving the uplink frame header from the ONU from the interface of the standby path is earlier than the time for receiving the uplink frame header of the ONU by the interface of the working path, the time is adjusted to be T, and the interface of the standby path uses a clock frame header which lags behind the interface of the working path by T moment as a downlink frame header.
A switching control unit 19, configured to control switching from the interface of the working path to the interface of the standby path after the adjusting unit 17 adjusts the time for the interface of the standby path to send the downlink frame header.
The first time obtaining unit 11 and the second time obtaining unit 12 in the master-slave switching device may only need to be any one of them, or may exist in both cases. In addition, the first time obtaining unit 11 may record the time for sending the downlink frame header by the interface function module of the working path through monitoring the interface function module of the working path, and/or may obtain the time for sending the downlink frame header from the interface of the working path according to the detected synchronization signal by detecting the synchronization signal. The first time obtaining unit 11 records the time when the uplink frame header reaches the interface function module of the standby path by monitoring the interface function module of the standby path, so as to obtain the time when the uplink frame header is received from the interface of the standby path. The second time obtaining unit 12 may monitor the interface function module of the working path and the interface function module of the standby path, start timing when detecting that the interface function module of the working path sends the downlink frame header, and end timing when detecting that the interface function module of the standby path receives the uplink frame header, so as to obtain a time difference between sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path.
Fig. 4 shows a specific example based on fig. 3. The embodiment of the invention provides network equipment in a passive optical network, which is responsible for service processing distribution, ONU management, synchronous clock processing and the like. In an embodiment of the present invention, as shown in fig. 4, the network device 300 includes:
one or more network side service interface function modules PON NT380 are responsible for receiving and transmitting service data messages and/or management messages with upper network devices.
When the interface of the working path corresponding to the interface of the standby path needs to be switched, the interface of the working path can be switched to the interface of the standby path.
At least two logically independent line interface function modules PON LT340, which correspond to one interface respectively, complete line interface termination, and communicate with a network side service interface function module 380. Each line interface function module PON LT340 includes at least one optical-to-electrical conversion module 342 and at least one message processing module 344, for example, PON LT340-1 includes two optical-to-electrical conversion modules 342-11 and 342-12 and one message processing module 344-1. The message processing module 344 is responsible for service processing, synchronous clock processing, frame header processing, and other functions. The photoelectric conversion module 342 realizes photoelectric conversion and/or electro-optical conversion, and may be a module integrating transmission and reception or a module separating transmission and reception. The two photoelectric conversion modules respectively arranged on the message processing modules 344-1 and 344-M in the device described in fig. 4 are only an example, and the photoelectric conversion modules connected to each message processing module are not limited, and may be one, two, three, or four, and so on. In this context, two photoelectric conversion modules are taken as an example, and are not described again unless otherwise specified.
In this embodiment of the present invention, to implement the protection switching function, the network device 300 includes a control module 360, which is capable of performing the control function of protection switching, and the structure of the control module 360 is consistent with that of the switching device shown in fig. 3, and includes a first time obtaining unit 11 and/or a second time obtaining unit 12, an adjustment time obtaining unit 13, a storage unit 15, an adjustment unit 17, and a switching control unit 19. The functions of these units of the control module 360 are shown in the specific structure and description of the switching device in fig. 3, and will not be described repeatedly here. Wherein the light receiving module 342-11 and the light emitting module 342-12 can also be a transceiver module (not shown). Taking the PON LT340-1 as an interface function module of a working path and the PON LT340-M as an interface function module of a standby path as an example, the message processing module 344-1 sends a downlink frame header to the control module 360, and the message processing module 344-M sends a received uplink frame header to the control module 360, so that the first time acquiring unit and/or the second time acquiring unit of the control module 360 can acquire a time from sending the downlink frame header from the interface of the working path to receiving the uplink frame header from the interface of the standby path according to frame headers sent by the message processing module 340-1 and the message processing module 340-M. The frame header synchronization module 390 may further provide the downlink synchronization clock signal to the control module 360, so that the control module 360 may obtain the time for sending the downlink frame header from the main port according to the downlink synchronization clock signal or use the time as a reference for sending the downlink frame header from the main port.
Fig. 5 is a schematic diagram of another network device according to an embodiment of the present invention. Network device 400 in fig. 5 includes at least two PON LTs 420 (e.g., PON LT 420-1.,. 420-M), a network-side traffic interface module 380, and a frame header synchronization module 390. Similar to the PON LT340 in fig. 4, each PON LT includes at least one message processing module, and each message processing module 344 is coupled to at least one optical-to-electrical conversion module 342, for example, the PON LT420-1 includes a message processing module 344-1 and optical-to-electrical conversion modules 342-11 and 342-12. Unlike the PON LT340 in fig. 4, each PON LT420 includes a control module 360, which is coupled to the PON LT where the PON LT is located and the message processing modules on other PON LTs, and is capable of receiving the frame headers sent by the message processing modules. Specifically, for example, the PON LT420-M is an interface function module of the standby path, and the PON LT420-1 is an interface function module of the working path, and the control module 360-M performs the switching control function, the control module 360-M receives the downlink frame header sent by the message processing module 344-1 and receives the uplink frame header sent by the message processing module 344-M, so as to obtain two times of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path, and/or obtain a time difference between a time of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path. The PON LT420-M may also obtain the time for the main port to send the downlink frame header through a clock signal provided by the frame header synchronization module 390 or use the time as a reference for sending the downlink frame header from the main port. By using the switching device provided by the above embodiment of the present invention, the time for sending the downlink frame header from the interface of the standby path is adjusted, so that the downlink frame header sent from the interface of the standby path is consistent with the interface of the working path from the time when the downlink frame header sent from the interface of the working path reaches the ONU.
In the embodiment of the invention, 1:1 protection can be realized, and 1: N protection can also be realized. Wherein, the protection of '1: 1' indicates that the interface of each working path has an interface of a standby path for backup; "1: N" protection means that the interfaces of the N working paths share the interface of one backup path. The implementation method of the "1: N" protection is similar to that of the "1: 1" protection, and the description is not repeated here.
According to the embodiment of the invention, the optical access system comprises an optical line terminal and an optical network terminal, wherein a connection path between the optical line terminal and the optical network terminal comprises a working path and a standby path, the optical line terminal comprises a first interface and a second interface, the first interface is coupled with the working path, the second interface is coupled with the standby path, the optical line terminal is used for acquiring time of two time points for sending a downlink frame header from the first interface and receiving an uplink frame header from the second interface and/or time difference between the two time points, and acquiring adjustment time for sending the downlink frame header from the second interface according to the time of the two time points and/or the time difference between the two time points; and adjusting the time for sending the downlink frame header from the second interface according to the adjustment time for sending the downlink frame header from the interface of the standby path, and executing the switching from the working path to the standby path.
The switching control method of the corresponding control function module in fig. 2, 3, and 4 is further described below. Taking the line interface function module PON LT420-M as a backup of PON LT420-1 as an example, the optical-to-electrical conversion module 342-11 is an optical transmission module, the optical-to-electrical conversion module 342-12 is an optical reception module, the optical-to-electrical conversion module 342-M1 is an optical transmission module, the optical-to-electrical conversion module 342-M2 is an optical reception module, that is, a downlink optical signal sent by the optical-to-electrical conversion module 342-11 is sent to an optical network terminal through a working path (or called as a main path), and the optical-to-electrical conversion module 342-M2 receives an uplink optical signal from a backup path.
In the normal communication process, the time for sending the downlink frame header from the interface of the working path and the time for receiving the uplink frame header from the interface of the standby path are obtained, and/or the time difference between the time for sending the downlink frame header from the main interface and the time for receiving the uplink frame header from the interface of the standby path is obtained, when the interface of the working path needs to be switched to the interface of the standby path, the time for sending the downlink frame header from the interface of the standby path is adjusted according to the obtained time and/or time difference, so that the time for the downlink frame header sent from the interface of the standby path and the time for the downlink frame header sent from the interface of the working path to reach the ONU are consistent, and the switching from the interface of the working path to the interface of the standby path is executed after the time adjustment, thereby realizing the active.
Specifically, as shown in fig. 6, the OLT device switching method in the embodiment of the present invention includes the following steps:
step s601, obtaining the time of two time points of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path, and/or obtaining the time difference between the time of sending the downlink frame header from the main interface and the time of receiving the uplink frame header from the interface of the standby path;
step s602, adjusting the time for sending the downlink frame header from the interface of the standby path according to the time of the two time points and/or the time difference between the two time points, so that the time is consistent with the time for the downlink frame header sent from the interface of the working path to reach the ONU.
And step s603, executing the switching from the interface of the working path to the interface of the standby path.
Specifically, in the embodiment of the present invention, the time of two time points when the downlink frame header is sent from the interface of the working path and the uplink frame header is received from the interface of the standby path and/or the time difference between the two time points may be obtained by monitoring the interface function module of the working path and the interface function module of the standby path; the method adopts a method of sending frame headers mutually, when an interface function module of a working path sends a downlink frame header to an ONU (optical network unit), the downlink frame header is simultaneously sent to a control module, for example, the downlink frame header is driven into two paths, one path is sent to the ONU, and the other path is sent to the control module. The control module can obtain the position of the downlink frame header of the interface of the working path after receiving the downlink frame header sent by the interface function module of the working path, the time point of the position of the downlink frame header can be recorded by an internal high-frequency clock, and the time for sending the downlink frame header by the interface of the standby path is adjusted when the interfaces are switched, so that the time for the downlink frame header sent by the interface of the standby path and the time for the downlink frame header sent by the interface of the working path to reach the ONU are consistent.
In another embodiment of the present invention, the frame header synchronization module and the interface function module of the standby path may also be monitored, and the time of two time points when the downlink frame header is sent from the interface of the working path and the uplink frame header is received from the interface of the standby path and/or the time difference between the two time points are obtained, where the frame header synchronization module provides the synchronization frame header of the interface of the working path and the synchronization frame header of the interface of the standby path. Two methods for obtaining the time for sending the downlink frame header from the interface of the working path are provided. The method adopts a method of synchronizing frame headers, and the frame header synchronizing module enables an interface function module of a working path and an interface function module of a standby path to send downlink frame headers synchronously, namely a control module directly detects a unified downlink synchronous frame header to obtain the time for sending the downlink frame header from a main interface, the position of the downlink frame header of the interface of the working path, the time point of the position of the downlink frame header can be recorded by an internal high-frequency clock, and the time for sending the downlink frame header from the interface of the standby path is adjusted when the interfaces are switched, so that the time for the downlink frame header sent from the interface of the standby path and the time for the downlink frame header sent from the interface of the working path to reach the ONU are consistent.
The control can be completed on an independent control functional entity, namely, the control module can be arranged on the independent control functional entity to perform centralized control on the interface functional modules of the plurality of working paths and the interface functional module of the protection line, and the centralized control of the plurality of line interface functional modules can be realized by adopting the mode, so that the system scheduling, the configuration maintenance and the management are more convenient, and particularly, the control complexity can be reduced by a protection system with 1: N or x: N (x represents a natural number greater than 1, and N represents a natural number greater than 1).
The above control can also be completed on the interface function module of the backup path with the control module, that is, the control module can be arranged on the interface function module of the backup path, and this way has more obvious protection advantage for 1:1 and more rapid protection switching.
In order to adjust the time for sending the downlink frame header by the interface function module of the standby path, the adjustment time needs to be obtained, and the method specifically includes:
the control module detects a position of a downlink frame header of the interface function module of the working path, and records a time T1 of the time point when receiving the downlink frame header sent by the interface function module of the working path or receiving a downlink frame header reference signal sent by the frame header synchronization module, specifically, the time point may be determined by an internal high-frequency clock. The interface function module of the backup path receives the uplink frame, records the time T2 of the time point when detecting the header of the uplink frame, and then calculates the adjustment time T by using T1 and T2, taking an uplink and downlink round-trip period as an example, the adjustment time T can be obtained by the following formula:
T＝T2-T1-2*Tf-Tr (1)
in the above formula (1), T2 indicates the time when the interface function module of the standby path receives the upstream frame header, T1 indicates the time when the interface function module of the working path sends the downstream frame header, Tf indicates the frame length period of one frame (for example, the frame length period of one frame in GPON is 125 μ s), and Tr is the response time of the ONU. Wherein Tf may be determined according to a frame length period specified by a system protocol, and Tr may include at least one of: the response time of the ONU, the waiting time delay and the equalizing time delay EQD of the ONU required by the system, and the like. In order to simplify the processing, the value of Tr can be replaced by a mean value; however, in consideration of the particularity of the ONUs and the line, an information table may be maintained, information such as the time Tr of each ONU and the times T2 and T1 of each ONU may be recorded, and the time T of each ONU may be calculated based on the information table.
According to the above description, the adjustment time T can be obtained by the following formula:
T＝ΔT-2*Tf-Tr (2)
in the above formula (2), Δ T ═ T2-T1 can be obtained by a timer, and by using this method, it is not necessary to know the specific time of each time point, but only the time between the two time points; tf and Tr are the same as in equation (1) and will not be described further.
It should be noted that the above equations (1) and (2) are not limited to the application of one uplink and downlink period, but may be extended to the application of multiple uplink and downlink periods, and in addition, simple changes in the equations, such as adding error adjustment time, are within the protection scope of the present invention.
Because the ONU has the following states: o1: the ONU is in an initial state after being powered on; (ii) a O2: the ONU waits for receiving the network parameter state; o3: the ONU waits for receiving a serial number request state; o4: a ranging state; o5: an operating state (normal state); o6: POPUP State (wait State); o7: an emergency stop state. If no traffic is received by the ONU, the ONU will enter O6 (waiting state) from O5 (normal state), or in a specific case such as data collision, the ONU will enter O7 from O5 (normal state): an emergency stop state. In order to solve the above problem, the frame header of the downlink frame may be sent by adjusting the interface function module of the standby path, so that the time for the downlink frame header sent by the interface of the standby path and the time for the downlink frame sent by the main interface to reach the ONU are consistent, and the ONU service reception is not affected, and the following specifically describes adjusting the time for the interface function module of the standby path to send the downlink frame header:
in order to adjust the time, it is also necessary to determine the adjustment direction, such as comparing the time of receiving the uplink frame header from the second interface with the time of sending the downlink frame header from the first interface; when the time for receiving the uplink frame header from the second interface is greater than the time for sending the downlink frame header from the first interface by a preset value, determining that the time needs to be advanced; and determining that delay is needed when the time for receiving the uplink frame header from the second interface and the time for sending the downlink frame header from the first interface are less than a preset value. This predetermined value may be set as the case may be, and as equations (1) and (2), the predetermined value may be set to 0; wherein the predetermined value is 2 x Tf + Tr if Δ T is directly compared.
When the interfaces need to be switched, if the switching time of the working line interface is T0, at this time, the time for sending the downlink frame header by the standby line interface is adjusted to T0-T, that is, if the adjustment time T is greater than 0, the time for sending the downlink frame header by the interface function module of the standby path is sent before T time, and if the adjustment time T is less than 0, the time for sending the downlink frame header by the interface function module of the standby path is sent after T time. Of course, the switching time T0 of the working line interface may not be known, for example, the time may be adjusted according to a reference time point of each frame sending period.
If the adjustment time T is greater than 0, that is, the sending time point is advanced, before the switching is performed, backup services such as an upper network or an upper service channel are firstly passed, and an interface function module of a backup working path manages information of the ONU, such as the equalization delay EQD. When the main and standby switch, the control module controls the interface function module of the working path to stop sending, the interface function module of the standby path is designated as the interface function module of the working path, the downlink sending is started, and the clock frame header at the adjusted sending time point is used as the downlink sending frame header.
If the adjustment time T is less than 0, namely the condition that the sending time point is delayed, because the time T is delayed after the downlink frame header sent from the interface of the standby path is compared with the time T of the downlink frame header sent from the interface of the working path, the time for the downlink frame header sent from the interface of the standby path to reach the ONU is consistent with the time for the downlink frame header sent from the interface of the working path to reach the ONU, the downlink frame header of the OLT does not change for the ONU, the ONU enters a re-registration and ranging state, a large amount of switching time is saved, meanwhile, the ONU does not go offline and has almost no influence on the service.
In addition, in order to make the time that the upstream frame header of the ONU reaches the interface of the switched working path meet the standard requirement, the EQD on the ONU needs to be updated, and many methods are used to update the EQD again, for example, according to g.984. standard, a command for updating the EQD is issued downstream, and the EQD is adjusted to the time of EQD-2T, so that the time that the upstream frame header of the ONU reaches the interface of the switched working path meets the standard requirement.
From the above description of the embodiments, it is clear for those skilled in the art that the present invention can be implemented by hardware, or by software plus a necessary general hardware platform, and based on such understanding, the technical solution of the present invention can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a usb disk, a removable hard disk, etc.), and includes several instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the method described in the embodiments of the present invention.
The above disclosure is only for a few specific embodiments of the present invention, but the present invention is not limited thereto, and any variations that can be made by those skilled in the art are intended to fall within the scope of the present invention.
Claims (11)
1. A switching method of an optical access system, where a local side of the optical access system includes a first interface and a second interface, the first interface is coupled to a working path, and the second interface is coupled to a standby path, the method comprising:
acquiring time of two time points for sending a downlink frame header from a first interface and receiving an uplink frame header from a second interface and/or time difference between the two time points;
acquiring the adjustment time for sending the downlink frame header from the second interface according to the time of the two time points and/or the time difference between the two time points;
and adjusting the time for sending the downlink frame header from the second interface according to the adjustment time, and executing the switching from the first interface to the second interface.
2. The method according to claim 1, wherein the obtaining the time of the two time points and/or the time difference between the two time points for sending the downlink frame header from the first interface and receiving the uplink frame header from the second interface comprises:
monitoring an interface function module of a first interface and an interface function module of a second interface, and acquiring time of two time points of sending a downlink frame header from the first interface and receiving an uplink frame header from the second interface and/or time difference between the two time points; or
And the frame header synchronization module is used for monitoring the frame header synchronization module and an interface function module of the second interface, and acquiring time of two time points for sending the downlink frame header from the first interface and receiving the uplink frame header from the second interface and/or time difference between the two time points, wherein the frame header synchronization module is used for providing the synchronization frame headers of the first interface and the second interface.
3. The method of claim 1, wherein the method further comprises:
comparing the time of receiving the uplink frame header from the second interface with the time of sending the downlink frame header from the first interface;
when the time for receiving the uplink frame header from the second interface is greater than the time for sending the downlink frame header from the first interface by a preset value, adjusting the time for sending the downlink frame header from the second interface to the time for sending the downlink frame header from the first interface to be earlier than the adjusting time;
and when the time for receiving the uplink frame header from the second interface and the time for sending the downlink frame header from the first interface are less than a preset value, adjusting the time for sending the downlink frame header from the second interface to be delayed by the time for sending the downlink frame header from the first interface.
4. The method of claim 1, wherein the method further comprises:
and sending a control frame to an optical user terminal, and updating the equalization time delay EQD on the ONU.
5. The method of claim 1, wherein the method further comprises:
the adjusting time is determined by the time of two time points of sending the downlink frame header from the first interface and receiving the uplink frame header from the second interface, the frame length period and the response time of the optical user terminal; and/or
The adjusting time is determined by the time difference between two time points of sending the downlink frame header from the first interface and receiving the uplink frame header from the second interface, the frame length period and the response time of the optical user terminal.
6. An optical line terminal is characterized in that the optical line terminal comprises a first interface function module, a second interface function module and a control module,
the first interface function module is used for providing an interface processing function of a working path;
the second interface function module is used for providing an interface processing function of a standby path;
the control module is configured to obtain time of the first interface function module sending the downlink frame header and time difference between two time points when the second interface function module receives the uplink frame header and/or time difference between two time points, obtain adjustment time of the second interface function module sending the downlink frame header according to the time of the two time points and/or the time difference between the two time points, adjust time of sending the downlink frame header from the second interface function module according to the adjustment time, and control switching from the first interface function module to the second interface function module.
7. The olt of claim 6, wherein the control module obtains, by monitoring the first interface function module and the second interface function module, times of two time points when the first interface function module sends the downlink frame header and the second interface function module receives the uplink frame header and/or a time difference between the two time points.
8. The OLT of claim 6, further comprising a frame header synchronization module to provide synchronization frame headers for the first interface function and the second interface function,
the control module acquires the time of two time points when the first interface function module sends the downlink frame header and receives the uplink frame header from the second interface function module and/or the time difference between the two time points by monitoring the frame header synchronization module and the second interface function module.
9. The olt of claim 6, further comprising an update module configured to update the EQD on the ONU, wherein the EQD that needs to be updated is sent to the ONU via a downstream frame.
10. An optical access system, characterized in that the optical access system comprises an optical line terminal and an optical network terminal, a connection path between the optical line terminal and the optical network terminal comprises a working path and a backup path, the optical line terminal comprises a first interface and a second interface, the first interface is coupled to the working path, the second interface is coupled to the backup path,
the optical line terminal is used for acquiring time of two time points and/or time difference between the two time points when the downlink frame header is sent from the first interface and the uplink frame header is received from the second interface, and acquiring adjustment time when the downlink frame header is sent from the second interface according to the time of the two time points and/or the time difference between the two time points; and adjusting the time for sending the downlink frame header from the second interface according to the adjustment time for sending the downlink frame header from the interface of the standby path, and executing the switching from the working path to the standby path.
11. A switching control device, comprising: an adjustment time obtaining unit, an adjustment unit and a switching control unit; the switching control device also comprises a first time acquisition unit and/or a second time acquisition unit; wherein,
the first time obtaining unit is used for obtaining the time of two time points of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path;
the second time obtaining unit is used for obtaining the time between two time points of sending the downlink frame header from the interface of the working path and receiving the uplink frame header from the interface of the standby path;
the adjustment time acquiring unit is used for calculating the adjustment time between the interface of the working path and the interface of the standby path according to the time acquired by the first time acquiring unit and/or the time difference acquired by the second time acquiring unit; the adjusting unit is used for adjusting the time for sending the downlink frame header from the interface of the standby path according to the adjusting time acquired by the adjusting time acquiring unit;
and the switching control unit is used for controlling the switching from the interface of the working path to the interface of the standby path after the adjusting unit adjusts the time for sending the downlink frame header from the interface of the standby path.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
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| CN200810126402A CN101615927A (en) | 2008-06-25 | 2008-06-25 | A kind of reverse method of multi-plexing light accessing system, device and system |
| PCT/CN2009/072291 WO2009155830A1 (en) | 2008-06-25 | 2009-06-16 | Exchanging method, equipment and system for the optical access system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN200810126402A CN101615927A (en) | 2008-06-25 | 2008-06-25 | A kind of reverse method of multi-plexing light accessing system, device and system |
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| CN101615927A true CN101615927A (en) | 2009-12-30 |
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| WO (1) | WO2009155830A1 (en) |
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| CN105763381A (en) * | 2016-04-14 | 2016-07-13 | 烽火通信科技股份有限公司 | Lossless processing method and system of main-standby switching messages |
| WO2019006704A1 (en) * | 2017-07-05 | 2019-01-10 | 华为技术有限公司 | Path computation method, apparatus and system |
| CN111654297A (en) * | 2017-08-30 | 2020-09-11 | 华为技术有限公司 | Dynamic time adjustment method, device and system |
| CN111866624A (en) * | 2020-06-16 | 2020-10-30 | 烽火通信科技股份有限公司 | ONU service migration method, device, equipment and readable storage medium |
| WO2021031153A1 (en) * | 2019-08-21 | 2021-02-25 | 华为技术有限公司 | Data processing device and system |
| WO2021259216A1 (en) * | 2020-06-23 | 2021-12-30 | 中兴通讯股份有限公司 | Authentication method, apparatus and device, and storage medium |
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| US7792017B2 (en) * | 2005-06-24 | 2010-09-07 | Infinera Corporation | Virtual local area network configuration for multi-chassis network element |
| CN101150361B (en) * | 2006-09-20 | 2011-06-22 | 北京格林威尔科技发展有限公司 | A method and system for realizing fully protective switching in passive optical network |
| CN101179334A (en) * | 2006-11-09 | 2008-05-14 | 英保达股份有限公司 | Optical fiber network alternate channel switch controller |
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| CN105763381A (en) * | 2016-04-14 | 2016-07-13 | 烽火通信科技股份有限公司 | Lossless processing method and system of main-standby switching messages |
| WO2019006704A1 (en) * | 2017-07-05 | 2019-01-10 | 华为技术有限公司 | Path computation method, apparatus and system |
| CN111654297A (en) * | 2017-08-30 | 2020-09-11 | 华为技术有限公司 | Dynamic time adjustment method, device and system |
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| WO2021031153A1 (en) * | 2019-08-21 | 2021-02-25 | 华为技术有限公司 | Data processing device and system |
| CN111866624A (en) * | 2020-06-16 | 2020-10-30 | 烽火通信科技股份有限公司 | ONU service migration method, device, equipment and readable storage medium |
| CN111866624B (en) * | 2020-06-16 | 2022-09-02 | 烽火通信科技股份有限公司 | ONU (optical network Unit) service migration method, device and equipment and readable storage medium |
| WO2021259216A1 (en) * | 2020-06-23 | 2021-12-30 | 中兴通讯股份有限公司 | Authentication method, apparatus and device, and storage medium |
| CN116131932A (en) * | 2021-11-12 | 2023-05-16 | 华为技术有限公司 | Method, device and equipment for calculating protection switching time |
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