APR protection method and device based on board card

Abstract

The invention provides an APR protection method based on a board card, and the method comprises the following steps: when any side of the board card meets an APR activation condition, i.e., a port where an OSC at the same side of the board card and a switch chip are linked detects physical interruption of a link signal, and EDFA light receiving LOS at the same side of the board card for receiving a line signal, all EDFA lasers at two sides of the board card are turned off; and when any side of the board card meets an APR deactivation condition, namely, the physical link of the OSC at the side of the board card is connected, and the double verification of the notification information in the single-disk management information is passed according to the service sensitivity level configured at the side of the board card, the APR at the side is deactivated, so that the EDFA at the side is recovered. According to the scheme, on the premise of confirming that optical fiber connection is intact on a physical level, management can be carried out on a software level, line turn-off and recovery logic are designed according to pairing information, information verification between devices is provided, and protection of human eye safety and protection of services and the devices can be taken into consideration.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technologies, and in particular, to a board-based APR protection method and apparatus. Background Art

[0002] In a data center interconnection system, an optical fiber communication network is used as a transmission network. The optical power in a long-distance optical system is relatively high. Once the optical fiber is accidentally broken due to construction or the optical fiber is pulled out of the connector during the operation and maintenance process, the leaked light will directly damage the human eye and pose a great danger. Therefore, the device needs to activate an Automatic Power Reduction (APR) mechanism to reduce the optical power in the optical fiber line to a safe range, thereby playing a role in protecting the eyes.

[0003] A patent with the patent number CN101882958B discloses an APR protection method and apparatus. By adding an optical coupler at the end of the transmission optical fiber, a part of the optical power is coupled to another board of the destination site for signal detection, and the detection result is compared with a threshold value to determine whether it is necessary to reduce the output optical power.

[0004] However, considering that a large number of optical devices are deployed in data center servers, different devices carry different service traffic, and different devices have different requirements for the input optical power. During manual maintenance, it is inevitable that the problem of incorrect optical fiber connection to devices occurs. At this time, corresponding measures should be taken to cut off the transmission of services when the system is interrupted and to check whether the connection of system devices meets the expectations before restoring the services. At the same time, different customers have different requirements for the APR protection of devices. There may be some lines that require strict verification of the devices at both ends of the line, while some lines do not. At the same time, when the APR protection function is activated, there are also different control requirements for the laser. Summary of the Invention

[0005] Based on the problems existing in the above-mentioned prior art, the present invention aims to solve the technical problem that the protection logic of the APR protection method in the prior art is single and it is impossible to determine whether the devices at both ends of the optical fiber belong to two devices with service pairing.

[0006] The present invention provides a board-based APR protection method. The APR protection includes an APR activation process and an APR deactivation process, and it includes the following steps:

[0007] When any side of the board meets the APR activation condition, turn off the lasers of all EDFAs on both sides of the board; wherein, the APR activation condition on any side of the board is that the port where the OSC on the same side of the board is linked to the switching chip detects a physical interruption of the link signal, resulting in link down; and the EDFA receiving the line signal on the same side of the board has a loss of optical signal (LOS).

[0008] When the APR deactivation conditions are met on both sides of the board, the lasers of the EDFAs on both sides are restored simultaneously. Among them, the APR deactivation condition on any one side of the board is as follows: the physical link of the OSC on this side of the board is connected, and according to the service sensitivity level configured on this side of the board, the double verification of the notification information in the single-board management information passes. The function of the single-board management information is to identify and match with other devices through identification, inform the line conditions of the receiving side at this end, and send the notification information and the line-side matching result.

[0009] According to an embodiment of the present invention, the double verification of the notification information in the single-board management information includes: the sink notification information at this end is successfully matched, and the sink notification information at the opposite end is equal to the source notification information at this end.

[0010] According to an embodiment of the present invention, the matching rule of the sink notification information at this end is that the MCU in the board compares the sink expected information at the line end at this end with the source notification information sent from the opposite end. If the sink expected information is inconsistent with the source notification information, it is considered that the matching fails; if the sink expected information is consistent with the source notification information, it is considered that the matching is successful.

[0011] According to an embodiment of the present invention, the single-board management information is transmitted using the LLDP protocol or a custom single-board management information frame structure.

[0012] According to an embodiment of the present invention, when the single-board management information is defined with a custom single-board management information frame structure, the single-board management information includes a frame header, a data length, a data body, a check field, and a frame tail.

[0013] According to an embodiment of the present invention, the data body includes a service sensitivity level. Setting the service sensitivity level can meet the different emphases and requirements of different optical transmission systems for human eye protection and service protection. According to the configured service sensitivity level, the board will have different EDFA operation permissions during the APR protection period and different APR recovery conditions.

[0014] According to an embodiment of the present invention, the data body further includes a Source port ID, line status information, Source notification information, Sink notification information, Sink expected information, and a notification matching result.

[0015] According to an embodiment of the present invention, the forwarding of the single-board management information is implemented by the switching chip SW in the board, and the single-board management information sent from the opposite end is received.

[0016] According to an embodiment of the present invention, when the APR deactivation conditions are met on both sides of the board, the lasers of the EDFAs on both sides are restored simultaneously, including the following steps:

[0017] Determine whether either side of the board meets the APR deactivation condition. If it does, deactivate the APR on that side and proceed to the next step.

[0018] Determine whether the other side of the board meets the APR deactivation condition. If it does, deactivate the APR on that side, and simultaneously restore the lasers of the EDFAs on both sides.

[0019] An APR protection method based on a board provided by the present invention has the following beneficial effects:

[0020] (1) This solution can complete information transmission and verification only using the board, without relying on a network manager.

[0021] (2) Use the OSC channel to transmit data. With the help of the existing network protocol format or a custom management frame format, on the premise of physically confirming that the optical fiber connection is intact, management will also be carried out at the software level.

[0022] (3) This solution designs the line shutdown and restoration logic relying on the pairing information. On the one hand, it provides information verification between devices, which can take into account the protection of human eye safety and the protection of services and devices; on the other hand, the design of the "service sensitivity level" field in the device information enables the device to perform APR protection as needed under different protection emphases, and can also effectively protect any device in a multi-level transmission network with repeaters. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] To more clearly illustrate the technical solutions in the embodiments or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is a flowchart of an APR protection method based on a board provided by an embodiment of the present invention;

[0025] Figure 2 It is a schematic structural diagram of an OTA board in an embodiment of the present invention;

[0026] Figure 3 It is a schematic structural diagram of an OLA board in an embodiment of the present invention;

[0027] Figure 4 It is a schematic diagram of the port direction of an OTA board in an embodiment of the present invention;

[0028] Figure 5 It is a schematic diagram of the port direction of an OLA board in an embodiment of the present invention;

[0029] Figure 6 It is a schematic diagram of the transmission direction of the service sensitivity level in the embodiment of the present invention;

[0030] Figure 7 It is a schematic diagram of an optical fiber communication network in Scenario 1 in the embodiment of the present invention;

[0031] Figure 8 It is a schematic diagram of an optical fiber communication network in Scenario 2 in the embodiment of the present invention;

[0032] Figure 9 It is a schematic diagram of an optical fiber communication network in Scenario 3 in the embodiment of the present invention. Specific embodiments

[0033] The following descriptions of the embodiments refer to the attached drawings to illustrate specific embodiments in which the present invention can be implemented.

[0034] The present invention provides a board-based APR protection method, and its process is as Figure 1 shown. The APR protection includes two processes: APR activation and APR deactivation. In order to record the APR activation / deactivation status on one side of the board, we introduce a flag parameter to mark the APR activation / deactivation status. When the APR activation / deactivation condition is met, set flag = 1; otherwise, set flag = 0.

[0035] For the APR activation process, when either side of the board meets the APR activation condition, that is, when the port where the OSC on the same side of the board is linked to the switching chip detects a physical interruption of the link signal, resulting in link down; and when the EDFA receiving the line signal on the same side of the board has a loss of optical signal (LOS), activate the APR on that side, that is, set the activation flag on that side to 1. Then, determine whether the APR activation status on that side meets the condition that the activation flag == 1. If it meets, turn off the lasers of all EDFAs (erbium-doped fiber amplifiers) on both sides of the board. At the same time, the side where the APR protection is activated reports the status of the activated APR protection.

[0036] For the APR deactivation process, when either side of the board meets the APR deactivation condition, that is, when the physical link of the OSC on that side of the board is connected, and the double verification of the notification information in the single-disk management information passes according to the service sensitivity level configured on that side of the board, deactivate the APR on that side, that is, set the deactivation flag on this side to 1. Then, determine whether the APR deactivation status on that side meets the condition that the deactivation flag == 1. If it meets, determine whether the other side meets the APR deactivation condition. If it meets, deactivate the APR on the other side, that is, set the deactivation flag on the other side to 1, and at the same time, all EDFAs in the board are restored. In addition, the APR function on either side is allowed to be configured to be turned on or off. When the APR function on one side is turned off, that side is defaulted to meet the deactivation condition.

[0037] The single board forwards the single board management information through the switching chip SW and receives the single board management information sent by the peer end. The function of the single board management information is to identify and match with other devices through identification, inform the line status of the receiving side of the local end, and send notification information and the line side matching result. The single board management information can be transmitted using the LLDP protocol or a custom single board management information frame structure.

[0038] The double verification of the notification information in the single board management information includes: the sink notification information of the local end matches successfully, and the sink notification information of the peer end is equal to the source notification information of the local end.

[0039] Among them, the matching rule of the sink notification information of the local end is that the MCU in the board card compares the sink expected information of the local end of the line with the source notification information sent by the peer end. If the sink expected information is inconsistent with the source notification information, it is considered a matching failure; if the sink expected information is consistent with the source notification information, it is considered a matching success.

[0040] The single board management information is transmitted using the LLDP protocol or a custom single board management information frame structure. When the single board management information is defined in a private frame format, the single board management information includes a frame header, data length, data body, check field, and frame tail. The data body includes Source port ID, service sensitivity level, line status information, Source notification information, Sink notification information, Sink expected information, and notification matching result.

[0041] Among them, in the Source port ID, the definition method of the ID is diverse. The purpose is to determine the device location to which the port belongs and the actual physical port used, including but not limited to using ASCII code or hexadecimal numbers. For example, it can be defined in the way of single board location + OSC number.

[0042] The service sensitivity level indicates the service sensitivity level of the port on this side. The service of level 1 is the most sensitive, and the sensitivity decreases gradually. Setting the service sensitivity level is to meet the different emphases and requirements of different optical transmission systems for human eye protection and service protection needs. According to the configured service sensitivity level, the board card will have different EDFA operation permissions during the APR protection period and different APR recovery conditions.

[0043] Specifically, a total of 4 service sensitivity levels are set in the embodiments of the present invention. The characteristics of Level 1 are as follows: (1) When in the protection state, the EDFA cannot be made to emit light by manually configuring the EDFA laser; (2) It is necessary to satisfy the successful matching of the physical recovery of the link and the port notification information before exiting the protection and restoring the laser emission. The characteristics of Level 2 are as follows: (1) When in the protection state, the EDFA cannot be made to emit light by manually configuring the EDFA laser; (2) As long as the physical recovery of the link is satisfied, without the need for the successful matching of the port notification information, the protection can be exited and the laser emission can be restored. The characteristics of Level 3 are as follows: (1) When in the protection state, the EDFA can be made to emit light by manually configuring the EDFA laser; (2) It is necessary to satisfy the successful matching of the physical recovery of the link and the port notification information before exiting the protection and restoring the laser emission. The characteristics of Level 4 are as follows: (1) When in the protection state, the EDFA can be made to emit light by manually configuring the EDFA laser; (2) As long as the physical recovery of the link is satisfied, without the need for the successful matching of the port notification information, the protection can be exited and the laser emission can be restored.

[0044] The line status information includes the EDFA LOS status, OSC link, etc. The Source notification information is the information sent from this device through this port, including but not limited to being defined using ASCII code or hexadecimal numbers. The Sink notification information is the information received by this device through this port, including but not limited to being defined using ASCII code or hexadecimal numbers. The Sink expected information is the information that this device expects to receive through this port, including but not limited to being defined using ASCII code or hexadecimal numbers. The notification matching result is the comparison result between the Sink notification information and the Sink expected information of this port, including: 0 - not verified, 1 - verified successfully, 2 - verified failed.

[0045] Specifically, according to the different line positions, the boards in the embodiments of the present invention are divided into end - station boards (OTA) and relay - station boards (OLA). The structure of the end - station board (OTA) is as Figure 2 shown, which includes: 1 optical power amplifier BA, 1 pre - amplifier PA, 1 optical channel detection module, 1 switching chip SW. Among them, the MCU controls BA, PA, OSC, and the switching chip SW through management signals. The data channels of the switching chip SW are respectively connected to the MCU and the OSC module to realize the forwarding of single - board management information and the reception of single - board management information sent from the end.

[0046] The structure of the relay - station board (OLA) is as Figure 3As shown in the figure, it includes: 2 relay amplifiers, 2 optical channel detection modules OSC, 1 switching chip, and 1 MCU. Among them, the MCU controls LA, OSC, and the switching chip SW through management signals. The data channels of the switching chip SW are respectively connected to the MCU and the OSC module to realize the forwarding of single-board management information and the single-board management information sent from the opposite end.

[0047] Definition of port direction: As Figure 4 shown, for the OTA board, it is divided into the Signal side and the Line side; as Figure 5 shown, for the OLA board, it is divided into the west side and the east side.

[0048] The APR protection function protects the safety of optical power transmission on the transmission line side. Based on this, for the OTA board, APR protection is required for the LINE side; for the OLA board, both its WEST side and EAST side need to have the ability of APR protection and judge independently of each other without affecting each other. Please continue to refer to Figure 4 , for OTA, when the port where OSC1 on the LINE side is linked to the switching chip has a link down due to fiber breakage and the PA receives light with LOS, the APR protection trigger condition is satisfied. Please continue to refer to Figure 5 , for OLA, when OSC1 on the WEST side has a link down and LA1 receives light with LOS, or OSC2 on the EAST side has a link down and LA2 has LOS, both belong to the situation where the APR protection trigger condition is satisfied, and the corresponding side's APR protection action will be activated.

[0049] Transmission of service sensitivity level: After the service sensitivity level in the single-board management information is transmitted to the next port through the OSC, it may affect the configuration of the service sensitivity level on the same side of the device where the next port is located. For example, Figure 6 shown, the board B sends the single-board management information carrying the service sensitivity level to board A through the OSC1 port in the WEST direction. Board A will compare the service sensitivity levels in the A-EAST direction of this device and the B-WEST direction of device B and synchronize to the higher sensitivity level.

[0050] To facilitate the understanding of the working principle of an APR protection method based on a board provided in the embodiments of the present invention, the following lists 3 scenarios for illustration:

[0051] Scenario 1

[0052] As Figure 7 shown, since the light breakage point does not belong to the line side and there is no situation where OSC link down and EDFA LOS occur simultaneously, the APR of any side is not activated.

[0053] Scenario 2

[0054] As Figure 8 shown, the APR entry logic is as follows: ① When 1 is disconnected, B does not receive the light of OSC1, OSC1 and OSC2 are link down, and LA1 has no light, activating the APR at the B end and turning off LA2 and LA1. ② When 2 is disconnected, A does not receive the light of OSC2, OSC1 and OSC2 are link down, and PA1 has no light, activating the APR at the A end and turning off BA1 and PA1.

[0055] The APR recovery logic is as follows: 2 recovers first, OSC1 and OSC2 are link down, A does not exit the APR, 1 also recovers, OSC1 and OSC2 are link up. At this time, if the service sensitivity level requirement verification notification information in the single-board management information of the A-side and B-side ports, then A and B directly exit the APR. Restore the setting status of LA2 and BA1, the LLDP fiber connection verification in the input direction of LA2 and BA1 passes, and restore the setting status of PA1 and LA1.

[0056] Scenario 3 (Scenario of fiber connection to the wrong device)

[0057] As Figure 9 shown, the APR entry logic is as follows: ① When 1 is disconnected, B does not receive the light of OSC1, OSC1 and OSC2 are link down, and LA1 has no light, activating the APR at the B end and turning off LA2 and LA1. Since LA2 is turned off, PA1 has no light and OSC1 is link down, activating the APR at the A end and turning off BA1 and PA1. ② When 2 is disconnected, C does not receive the light of OSC4, OSC3 and OSC4 are link down, and LA2 has no light, activating the APR at the C end and turning off LA2 and LA1. Since LA1 is turned off, PA2 has no light and OSC4 is link down, activating the APR at the D end and turning off PA2 and BA2.

[0058] The APR recovery logic (sensitivity level configured to require verification of port notification information): ① When 2 recovers but the device fiber is wrongly connected to other devices, OSC3 and OSC4 are link up, the local sink notification information on the D side matches, but when parsing the sink notification information of the peer in the single-board management information, it is found that it is not the source information of the local end, indicating that the fiber connection is incorrect. For protection purposes, C and D do not exit the APR. ② After 1 recovers, if the A and B sides can meet the double verification of the notification information, then A and B exit the APR and restore the setting states of BA1 and LA2. The APR on the B side is not activated, but the APR on the C side is still activated, so LA1 and LA2 are not restored.

[0059] In summary, the APR protection method based on a board card provided by the present invention uses the channels of the OSC to transmit data. With the help of the existing network protocol format or a custom management frame format, on the premise of confirming the integrity of the optical fiber connection at the physical level, management is also carried out at the software level. At the same time, the scope of APR protection is expanded. It not only adds the protection of services and devices on the basis of protecting the safety of the human eye, but also can play a role in a multi-level transmission network with relays without affecting the implementation of functions.

[0060] It should be noted that although the present invention is disclosed above with specific embodiments, the above embodiments are not intended to limit the present invention. Those of ordinary skill in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is subject to the scope defined by the claims.

Claims

1. A board-based APR protection method, wherein the APR protection includes an APR activation process and an APR deactivation process, characterized in that: The following steps are involved: When the APR activation conditions are met on either side of the board, the lasers of all EDFAs on both sides of the board are turned off. The APR activation conditions on either side of the board are: the port connected to the OSC on the same side of the board and the switch chip detects a physical interruption of the link signal, and a link down occurs; and the EDFA receiving the line signal on the same side of the board receives LOS. When both sides of the board meet the APR deactivation conditions, the lasers of the EDFA on both sides are restored at the same time; the APR deactivation conditions on either side of the board are: the physical link of the OSC on that side of the board is connected, and according to the service sensitivity level configured on that side of the board, the double check of the notification information in the single-disk management information is passed; the function of the single-disk management information is to identify and match through identification and other devices, inform the line status of the receiving side of this end, and send notification information and line side matching results.

2. The board-based APR protection method according to claim 1, characterized in that: The double check of the notification information in the single disk management information includes: the sink notification information of the local end matches successfully, and the sink notification information of the other end is equal to the source notification information of the local end.

3. The board-based APR protection method according to claim 2, characterized in that: The matching rule of the sink notification information of the local end is that the MCU in the board compares the sink expectation information of the local end of the line with the source notification information sent by the other end. If the sink expectation information and the source notification information are inconsistent, the match is considered to have failed; if the sink expectation information and the source notification information are consistent, the match is considered to have succeeded.

4. The board-based APR protection method according to claim 1, characterized in that: The single disk management information is transmitted using the LLDP protocol or a custom single disk management information frame structure.

5. The board-based APR protection method according to claim 4, characterized in that: When the single disk management information is defined in a custom single disk management information frame structure, the single disk management information includes a frame header, a data length, a data body, a check field, and a frame tail.

6. The board-based APR protection method according to claim 5, characterized in that: The data body includes a service sensitivity level. Setting the service sensitivity level can meet the different emphasis and requirements of different optical transmission systems for human eye protection and service protection. According to the configured service sensitivity level, the board will have different EDFA operation permissions during the APR protection period and different APR recovery conditions.

7. The board-based APR protection method according to claim 6, characterized in that: The data body also includes Source port ID, line status information, Source notification information, Sink notification information, Sink expectation information and notification matching results.

8. The board-based APR protection method according to claim 1, characterized in that: The forwarding of the single disk management information is realized by the switching chip SW in the board, and the single disk management information sent by the opposite end is received.

9. The board-based APR protection method according to claim 1, characterized in that: When both sides of the board meet the APR deactivation conditions, the lasers of the EDFAs on both sides are restored at the same time, including the following steps: Determine whether any side of the board meets the APR deactivation conditions. If so, deactivate the APR on that side and proceed to the next step. Determine whether the APR deactivation condition is met on the other side of the board. If so, the APR on that side is deactivated, and the lasers of the EDFAs on both sides are restored at the same time.

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