WO2017148093A1 - Dispositif de nœud et procédé de commutation de réseau annulaire - Google Patents

Dispositif de nœud et procédé de commutation de réseau annulaire Download PDF

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Publication number
WO2017148093A1
WO2017148093A1 PCT/CN2016/092372 CN2016092372W WO2017148093A1 WO 2017148093 A1 WO2017148093 A1 WO 2017148093A1 CN 2016092372 W CN2016092372 W CN 2016092372W WO 2017148093 A1 WO2017148093 A1 WO 2017148093A1
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Prior art keywords
ring network
node
switching
unknown packet
ring
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Ceased
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PCT/CN2016/092372
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English (en)
Chinese (zh)
Inventor
游莉萍
吴克巍
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ZTE Corp
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ZTE Corp
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/42—Loop networks
    • H04L12/437—Ring fault isolation or reconfiguration
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/06—Management of faults, events, alarms or notifications
    • H04L41/0654—Management of faults, events, alarms or notifications using network fault recovery
    • H04L41/0659—Management of faults, events, alarms or notifications using network fault recovery by isolating or reconfiguring faulty entities
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/28—Routing or path finding of packets in data switching networks using route fault recovery

Definitions

  • the present application relates to, but is not limited to, the field of network communications, and in particular, to a handover scheme of a ring protection network.
  • the ring network protection protocol (the ERPS (Ethernet Ring Protection Switching) protocol described in G.8032 is used as an example.)
  • the RPL Ring Protection Link ring protection link
  • the ring network switching mainly occurs in the following scenarios (here, the ERPS ring network works in the return mode as an example): the ring network detects the link fault; the ring network link fails to recover; manually or forcibly switches the ring network node; Or force the ring node to switch.
  • the switching time of the ring network must be less than 50 milliseconds, and the switching time should be as short as possible.
  • the rate limit of unknown packets is usually enabled. This is a security measure for attack defense and a guarantee for the bandwidth of packet forwarding.
  • each network node needs to clear the Layer 2 forwarding table because of changes in the network topology. This causes the service packets originally on the ring network to become unknown packets, and the packets are unknown by the system.
  • the rate limit of the packet rate limit is severe, which causes serious packet loss. In particular, when the packet rate before the ring network is switched, the packet loss is more obvious, and the switching performance of the ring network becomes worse (the switching time becomes longer). Meet the performance requirements of 50 milliseconds.
  • the present invention provides a node device and a ring network switching method, which can solve the problem of poor handover performance caused by the unknown packet rate limiting function in the related ring network switching process.
  • the present application discloses a ring network switching method, which includes:
  • each ring network node configures the unknown packets of the system to an unlimited speed. After the ring network is switched, each ring network node recovers the unknown packet rate limit function of the system.
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet rate limit.
  • the functional process includes:
  • the faulty node When the ring network detects a link fault, the faulty node notifies other ring network nodes that the link is faulty, and the ring network switches.
  • the faulty node and all ring network nodes that receive the link failure notification configure the unknown packet of the system to an unlimited speed
  • each ring network node recovers the unknown packet rate limit function of the system.
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet rate limit.
  • the functional process includes:
  • the fault recovery node When the ring network recovers, the fault recovery node notifies the other ring network nodes that the link is faulty and the ring network switches.
  • the fault recovery node and all ring network nodes that receive the link failure recovery notification configure the unknown packet of the system to an unlimited speed
  • the ring network protection link (RPL) autonomous node receives the link failure recovery notification, and notifies all ring network nodes to restore the system's unknown packet rate limiting function after the timer event ends.
  • the process that the RPL autonomous node notifies all ring network nodes to recover the unknown packet rate limiting function after the timer event ends includes:
  • the RPL autonomous node first sends a ring protection switch to restore the R-APS (NR, RB) message when the timer expires, the timer event ends, and the R-APS (NR, RB) message is sent again to notify each ring.
  • the network node recovers the system's unknown packet rate limit function.
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet rate limit.
  • the functional process includes:
  • the R-APS Ring-Automatic Protection Switching
  • MS manual switching
  • the manually switched node and all the ring network nodes that receive the R-APS message configure the unknown packet of the system to an unlimited speed;
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet rate limit.
  • the functional process includes:
  • the node that is manually switched off sends an R-APS (NR) message to other ring network nodes, and the ring network switches.
  • R-APS NR
  • the RPL autonomous node receives the R-APS (NR) message, and sends an R-APS (NR, RB) message to all ring network nodes and blocks the PRL link when the timer expires;
  • the ring network node that receives the R-APS (NR, RB) message releases the blocking caused by the manual switching command;
  • the RPL autonomous node After the ring network node is unblocked, the RPL autonomous node notifies the node that clears the manual switch and all the ring network nodes to recover the unknown packet rate limit function of the system.
  • the process for the RPL autonomous node to notify the node that clears the manual handover and all the ring network nodes to recover the unknown packet rate limit function of the system includes:
  • the RPL autonomous node notifies the clearing of the manually switched node and all ring network nodes to recover the unknown packet rate limiting function by resending the R-APS (NR, RB) message.
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet limit.
  • the speed function process includes:
  • the node that is forcibly switched When forcibly switching the ring network node port, the node that is forcibly switched sends an R-APS message indicating the forced switching (FS) to all ring network nodes, and the ring network switches.
  • FS forced switching
  • the node that is forcibly switched and all the ring network nodes that receive the R-APS message configure the unknown packet of the system to an unlimited speed;
  • each ring network node configures the unknown packet of the system to an unlimited speed, and after the ring network is switched, each ring network node recovers the unknown packet rate limit.
  • the functional process includes:
  • the node that is cleared forcibly switches sends an R-APS (NR) message to all ring network nodes, and the ring network switches.
  • R-APS NR
  • the ring network node that receives the R-APS (NR, RB) message releases the blocking caused by the forced switching command;
  • the RPL autonomous node After the congestion is released, the RPL autonomous node notifies the node that clears the forced handover and all the ring network nodes to recover the unknown packet rate limiting function of the system.
  • the process for the RPL autonomous node to notify the node that clears the forced handover and all the ring network nodes to recover the unknown packet rate limiting function of the system includes:
  • the RPL autonomous node notifies the node that has forcibly switched and all the ring network nodes to recover the unknown packet rate limiting function by resending the R-APS (NR, RB) message.
  • the application also discloses a node device, which includes:
  • the first unit is configured to configure the unknown packet of the system to be an unlimited speed during the switching of the ring network
  • the second unit is configured to restore the system's unknown packet rate limiting function after the ring network is switched.
  • the process of switching the ring network includes one or more of the following:
  • the present application also provides a computer readable storage medium storing computer executable instructions that, when executed, implement the ring switching method described above.
  • the system unknown packet is automatically set to an unlimited speed, and the speed limit function of the system is restored after the handover is completed.
  • the switching performance of the ring network can be improved without affecting the security of the system, and the implementation of the solution is extremely simple, and does not bring additional overhead to the system, and is easily implemented in related network devices.
  • FIG. 1 is a flowchart of a ring network switching method according to an embodiment of the present invention
  • FIG. 2 is a schematic diagram of networking in a normal working state according to an embodiment of the present invention
  • FIG. 3 is a schematic diagram of networking of a link failure in a ring network according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of a format of a R-APS PDU (Protocol Data Unit) packet according to an embodiment of the present disclosure
  • FIG. 5 is a schematic diagram of a format of R-APS specific information in the R-APS PDU packet shown in FIG. 4;
  • FIG. 6 is a schematic diagram of a node device according to an embodiment of the present invention.
  • this embodiment provides a ring network switching method, including the following operations:
  • each ring network node configures the unknown packets of the system to an unlimited speed. After the ring network is switched, each ring network node recovers the unknown packet rate limit function of the system.
  • the ring network switching involved in this embodiment includes ring network switching triggered by various conditions, for example, the following types:
  • the ring network is switched when the ring network detects a link fault.
  • the faulty node When the ring network detects a link failure, the faulty node sends an R-APS (SF) message to notify other ring network nodes of the link failure (that is, the ring network switch is considered to start), the failed node and all the messages received.
  • R-APS R-APS
  • the unknown packet speed limit value of the system is restored (that is, the speed limit function of the unknown packet of the recovery system is restored, and the unknown packet speed limit value of the recovery system in the following is Restore the system's unknown packet speed limit function).
  • the fault recovery node When the ring network recovers, the fault recovery node sends an R-APS (NR) message to notify other ring network nodes of link failure recovery (ie, it can be considered to start ring network switching), the fault recovery node and all rings that receive the message.
  • NR R-APS
  • the node sets the system's unknown packet rate limit value to an unlimited speed
  • the RPL owner node receives the R-APS (NR) message and notifies all ring nodes to recover the system's unknown packet rate limit value after a timer event ends.
  • the timer of the RPL owner node is a periodic timer, for example, a WTR (Wait to Restore) timer, that is, the WTR timer expires, and the RPL owner node starts to periodically send the R-APS (NR, RB).
  • the message after receiving the R-APS (NR, RB) message, each node starts to process the forwarding table clearing.
  • the RPL owner node can periodically send an R-APS (NR, RB) message to notify.
  • Each ring network node recovers the system's unknown packet rate limit value.
  • the RPL owner node receives the R-APS again (NR, All ring nodes of the RB) message recover the unknown packet rate limit value of the system.
  • the node that is manually switched When manually switching the ring node port, the node that is manually switched will send an R-APS message indicating the manual handover (MS) (ie, it can be considered to start the ring network handover), the manually switched node and all the rings that receive the message.
  • MS manual handover
  • the node sets the system's unknown packet rate limit value to an unlimited speed;
  • the node that is manually cleared will send an R-APS (NR) message (that is, start ring network switch), and the node that is manually switched or all ring nodes that receive the message will be unknown.
  • NR R-APS
  • the packet speed limit value is set to an unlimited speed
  • the RPL owner node receives the R-APS (NR) message, and after a timer event expires, it sends an R-APS (NR, RB) message and blocks the PRL link, thus receiving the R-APS (NR, RB).
  • the ring node of the message will cancel the blocking caused by the manual switching command, and then the RPL owner node notifies all ring nodes to restore the system's unknown packet rate limit value.
  • the RPL owner node may notify each ring network node to recover the unknown packet rate limit value by sending an R-APS (NR, RB) message again, and each ring network node receives the R-APS for the second time. (NR, RB) message can restore the system's unknown packet speed limit value.
  • the node that is forcibly switched will send an R-APS message indicating forced switching (FS) (that is, it can be considered to start ring network switching), the node that is forced to switch, and all rings that receive the message.
  • FS forced switching
  • the node sets the system's unknown packet rate limit value to an unlimited speed;
  • the node that is cleared for forced handover will send an R-APS (NR) message (that is, it can be considered to start the ring network handover), and the node that is forcibly switched or all ring nodes that receive the message will be unknown.
  • the packet speed limit value is set to an unlimited speed
  • the RPL owner node receives the R-APS (NR) message, sends an R-APS (NR, RB) message and blocks the PRL link after a timer event times out; receives the R-APS (NR, RB) message.
  • the ring network node cancels the blocking caused by the forced switching command.
  • the clearing of the forced switching is completed, and the RPL owner node notifies each ring network node to restore the system's unknown packet rate limit value.
  • RPL The owner node can notify each ring node to recover the unknown packet rate limiting function of the system by sending an R-APS (NR, RB) message again.
  • each node in the ring network needs to record the current unknown rate limit value of the system. If the user changes the speed limit value, the ring network node also needs to update the rate limit value. When the ring network switch is completed, the ring network node follows the ring network node. The updated speed limit value restores the system's unknown packet speed limit function.
  • the general networking of the embodiment of the present invention is as shown in FIG. 2.
  • a plurality of devices form a ring network and run an ERPS ring network protection protocol.
  • the RPL link can be configured as a link between any two devices in the ring network.
  • the port on the RPL link is blocked during normal operation.
  • nodes 1, node 2, node 3, and node 4 form a ring network.
  • the RPL link is the link between node 3 and node 4.
  • the port on node 4 is the owner node.
  • DUT1 and DUT2 simulate two network element devices that need to communicate in the live network.
  • the ports are respectively connected to the two ports of the tester, and the tester simulates the transceiver package.
  • the system sets the speed limit of the unknown packet, and the message between the tester ports A and B is a known packet, and is not subject to the speed limit control of the unknown packet.
  • the nodes in each ring record the current unknown packet rate limit of the system.
  • the tester's ports A and B communicate through DUT1—node4—node1—node2—node3—DUT2, as shown in Figure 2; when the non-RPL link in the ring network fails, the tester's Ports A and B communicate through DUT1—node4—node3—DUT2, as shown in Figure 3.
  • node1 and node2 After detecting a link fault, node1 and node2 set the device's unknown packet rate limit to an unlimited speed; block the faulty port and clear the MAC address forwarding table; periodically send an R-APS (SF) message to notify other ring network nodes of the link fault. .
  • R-APS R-APS
  • Node3 and node4 receive the R-APS (SF) message for the first time, set the device's unknown packet rate limit to unlimited speed; clear the MAC address forwarding table; node4 is the RPL-owner node, and the node4 node port is blocked.
  • R-APS SF
  • Node3 and node4 receive the R-APS (SF) message for the second time, and trigger the logic to clear the MAC address forwarding table according to the rules defined in G.8032.
  • SF R-APS
  • Node3 and node4 receive the R-APS (SF) message for the third time, and restore the unknown packet rate limit of the device. At this point, the network is already in a stable state of protection.
  • SF R-APS
  • the RPL-owner node node4 sends a message to notify the faulty node to recover the unknown packet rate limit value of the device.
  • node1 and node2 After receiving the message, node1 and node2 restore the unknown packet rate limit of the device.
  • a new message can be designed to notify the failed node, and the unknown packet rate limit value is restored. Since some reserved fields in the specific information field in the R-APS PDU field are unused, As shown in FIG. 4, these fields can be used to represent the message. For example, the status reserved bit in the status field in the R-APS specific information format in FIG. 5 can be used, and the status reserved bit is set to 00001 to indicate recovery. Unknown packet speed limit value message.
  • node1 and node2 After detecting the link fault recovery, node1 and node2 set the device's unknown packet rate limit to an unlimited speed; periodically send an R-APS (NR) message to notify other ring network nodes of link fault recovery.
  • R-APS NR
  • Node3 and node4 receive the R-APS (NR) message, and set the device's unknown packet rate limit to an unlimited speed; the RPL-owner node node4 turns on the WTR timer.
  • R-APS NR
  • Node2 receives the R-APS (NR) message from node1 and opens the port where the link failed before (according to the G.8032 protocol, the node ID of node2 is assumed to be greater than the node ID of node1).
  • NR R-APS
  • the WTR timer of the RPL-owner node node4 expires, the RPL-owner port is closed, the R-APS (NR, RB) message is sent, and the MAC address forwarding table is cleared.
  • Each node receives an R-APS (NR, RB) message, and clears the MAC address forwarding table according to the rules defined in G.8032;
  • Node1 receives the R-APS (NR, RB) message, starts the port with the link failure before, and stops sending the R-APS (NR) message.
  • each node receives the R-APS (NR, RB) message a second time, and the second received R-APS (NR, RB) message is used to notify each ring network node to recover each node.
  • Unknown packet speed limit value Unknown packet speed limit value.
  • the embodiment provides a node device, which can implement the method in the foregoing Embodiment 1, where the node device includes at least a first unit and a second unit.
  • the first unit is configured to configure the unknown packet of the system to be an unlimited speed during the switching of the ring network
  • the second unit is configured to restore the system's unknown packet rate limiting function after the ring network is switched.
  • the node device provided in this embodiment can implement the method in the foregoing embodiment. Therefore, for the other operations of the node device, refer to the corresponding content in the first embodiment, and details are not described herein again.
  • the embodiment of the invention further provides a computer readable storage medium, which stores computer executable instructions, and when the computer executable instructions are executed, implements the ring network switching method according to the first embodiment.
  • a program to instruct related hardware such as a processor, which may be stored in a computer readable storage medium, such as a read only memory, disk or optical disk. Wait.
  • all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits.
  • the module/unit (processor) in the foregoing embodiment may be implemented in the form of hardware, for example, by implementing an integrated circuit to implement its corresponding function, or may be implemented in the form of a software function module, for example, being stored in the memory by a processor.
  • the program/instruction in it to implement its corresponding function This application is not limited to any specific combination of hardware and software.
  • the embodiment of the present application provides a ring network switching method and a node device, which can improve the switching performance of the ring network without affecting the security of the system, and the implementation of the solution is extremely simple, and does not bring additional overhead to the system. It is easy to implement in related network devices.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
  • Small-Scale Networks (AREA)

Abstract

L'invention concerne un procédé de commutation de réseau annulaire, consistant : pendant le processus de commutation d'un réseau annulaire, en ce que chaque nœud de réseau annulaire configure un paquet inconnu d'un système de sorte qu'il n'ait pas de limite de vitesse, et jusqu'à l'achèvement de la commutation du réseau annulaire, en ce que chaque nœud de réseau annulaire récupère une fonction de limite de vitesse du paquet inconnu du système. L'invention concerne également un dispositif de nœud. Selon la solution technique, pendant la commutation d'un réseau annulaire, un paquet inconnu d'un système est automatiquement réglé pour n'avoir aucune limite de vitesse, et après l'achèvement de la commutation, une fonction de limite de vitesse du système est récupérée. De cette manière, la performance de commutation d'un réseau annulaire est améliorée, sans compromettre la sécurité d'un système.
PCT/CN2016/092372 2016-03-03 2016-07-29 Dispositif de nœud et procédé de commutation de réseau annulaire Ceased WO2017148093A1 (fr)

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CN201610122087.9A CN107154886A (zh) 2016-03-03 2016-03-03 一种节点设备及环网切换方法
CN201610122087.9 2016-03-03

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Cited By (1)

* Cited by examiner, † Cited by third party
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CN113645312A (zh) * 2021-08-25 2021-11-12 烽火通信科技股份有限公司 一种基于erps协议的子环网链路保护方法与装置

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CN103023769A (zh) * 2013-01-22 2013-04-03 烽火通信科技股份有限公司 Onu实现二层广播包和未知包转发的方法
CN103227753A (zh) * 2013-04-01 2013-07-31 北京东土科技股份有限公司 一种网络拥塞处理方法、系统及装置
CN103618723A (zh) * 2013-12-03 2014-03-05 北京东土科技股份有限公司 防止环网协议报文攻击设备cpu的方法及装置

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Publication number Priority date Publication date Assignee Title
CN103023769A (zh) * 2013-01-22 2013-04-03 烽火通信科技股份有限公司 Onu实现二层广播包和未知包转发的方法
CN103227753A (zh) * 2013-04-01 2013-07-31 北京东土科技股份有限公司 一种网络拥塞处理方法、系统及装置
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Publication number Priority date Publication date Assignee Title
CN113645312A (zh) * 2021-08-25 2021-11-12 烽火通信科技股份有限公司 一种基于erps协议的子环网链路保护方法与装置
CN113645312B (zh) * 2021-08-25 2023-07-18 烽火通信科技股份有限公司 一种基于erps协议的子环网链路保护方法与装置

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