KR100929132B1 - Apparatus and method for handling subscriber communication failure in passive optical network operated by L3 / L2 network - Google Patents

Abstract

The present invention relates to an apparatus and a method for processing subscriber communication failure in a passive optical network operated by an L3 / L2 network. The present invention relates to a method for processing an error in a packet transmitted from an L3 switch by monitoring a packet returned from an L2 subscriber station. And drop the normal packet by the packet loop in the passive optical network operated by L3 / L2 network by blocking the communication of the failed L2 subscriber station to prevent abnormal packet transmission. This is to solve the phenomenon.

Passive Optical Network, L3 / L2 Network, Packet Loop, Failure, Mac Table

Description

Communication error processing apparatus and method for a subscriber's equipment on Passive Optical Network based on L3 / L2 network

The present invention relates to an apparatus and a method for processing subscriber communication failure in a passive optical network operated by L3 / L2 network. In particular, a packet transmitted from an L3 switch in a passive optical network operated by L3 / L2 network is looped from an L2 subscriber station. The present invention relates to a technique for solving a service failure phenomenon caused by a drop of a normal packet generated when a loop is returned.

Passive Optical Network (PON) is an optical subscriber construction method that provides high-speed services based on fiber optics to businesses, SOHOs, and homes, and uses a splitter on an optical cable. ) Allows multiple optical network termination devices (ONU: Optical Network Unit or ONT: Optical Network Terminal) to be connected.

In Down Stream, OLT manages packets by allocating Logical Link Identifiers (LLIDs) for each ONU or ONT located at different distances. When the OLT registers the LLID of the ONU or ONT registered in the frame and inserts the LLID into the preamble of the frame, the ONU or ONT sends only the frame having its own LLID to the UI.

In contrast, in the upstream, the OLT checks the queue information of each ONU or ONT through a report message periodically received from the ONU or ONT, and dynamically grants to all ONUs or ONTs. The uplink time slots are allocated to manage packets in time division multiplexing (TDM).

However, when the passive optical network (PON) is operated by L3 (Layer 3) / L2 (Layer 2) network, if the packet transmitted from the L3 switch is looped back from ONU or ONT that is the L2 subscriber station, The L3 MAC address is learned in the L2 MAC table, and a normal packet is dropped, thereby causing a subscriber communication failure (service failure).

Traditionally, to solve this, administrators had to find and delete manually learned L3 Mac address entries, or wait for the L3 Mac address entries to age out.

Therefore, the present inventors have studied the automation technology that can handle and recover the communication failure of the passive optical network operated by L3 / L2 network more efficiently by automating such manual service failure handling.

The present invention has been invented under the above-mentioned object, and in the passive optical network operated by L3 / L2 network, a drop of a normal packet generated when a packet transmitted from an L3 switch returns from a L2 subscriber station looped back. It is an object of the present invention to provide an apparatus and method for handling subscriber communication failure in a passive optical network operated by an L3 / L2 network that can automatically solve a service failure phenomenon caused by the "

According to an aspect of the present invention for achieving the above object, the present invention monitors a packet transmitted from the L2 subscriber station to the L3 switch, when a packet having a source address of the L3 switch MAC address is received, It is characterized by judging that it occurred.

Still another object of the present invention is to prevent communication of an abnormal packet by blocking communication of an L2 subscriber station which has failed when a failure is detected.

According to the present invention, a packet transmitted from an L3 switch is looped from an L2 subscriber station in a passive optical network operated by L3 / L2 network to monitor a packet returned from the L2 subscriber station to detect a failure and furthermore, a failure of the L2 subscriber station By blocking the communication of no more abnormal packets, the normal packet drop caused by the loop of packets in the passive optical network operated by L3 / L2 network can be solved. Has a useful effect that can effectively prevent.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily understand and reproduce the present invention.

1 is a schematic diagram of a passive optical network operating in an L3 / L2 network. As shown in the figure, the passive optical network operated by the L3 / L2 network is configured by linking the L3 (Layer 3) network 20 and L2 (Layer 2) network 30 through the L3 switch 10.

The service provider (ISP) server 21 is interlocked with the L3 network 20, and the optical line termination (OLT) 31 is connected to the splitter 32 in the L2 (Layer 2) network 30. It is connected to several optical network units (ONU: Optical Network Unit or ONT: Optical Network Terminal) 33 to form a passive optical network (PON).

In down stream, the OLT inserts a Logical Link Identifier (LLID) corresponding to the destination address (DA) into the preamble of the transmission frame so that the source address (SA) is stored in the system. The destination address DA is transmitted to the L2 subscriber station by using the ONU or ONT, that is, the address of the L2 subscriber station.

The normal L2 subscriber station receives and processes only frames having its LLID among the transmitted frames. However, when a failure occurs in a specific L2 subscriber station, the transmission frame transmitted to the corresponding L2 subscriber station is not properly received and is returned in a loop.

The frame normally transmitted from the L2 subscriber station to the OLT has a source address (SA) of the L2 subscriber station and a destination address (DA) of the L3 MAC address. However, a looped frame has a source address (SA) as an L3 MAC address as a system address, and a destination address (DA) as an L2 subscriber station address.

In the process of transmitting a frame from the L2 subscriber station to the OLT, the OLT switches the packet by learning the MAC address and converts the source address (SA) of the transport packet into the LLID or the L2 subscriber station. Map to address and record in Mac table. The source address recorded in the MAC table is used for packet switching while remaining in the MAC table for a certain time.

However, when the transport packet is looped, since the source address (SA) of the frame has a L3 MAC address which is a system address, and the destination address (DA) has an L2 subscriber station address, the L2 subscriber station is included in the MAC table if the packet is originally a normal packet. The device address must be running, but otherwise the L3 Mac address is running as shown in FIG.

If the L3 MAC address is incorrectly learned by the loop packet, a normal packet is dropped by the L3 MAC address, resulting in a service failure. FIG. 2 is a diagram illustrating an example of an L2 MAC table in which an L3 MAC address is incorrectly learned.

3 is a block diagram according to an embodiment of a subscriber communication failure processing apparatus of a passive optical network operated by L3 / L2 network according to the present invention. The subscriber communication failure processing apparatus of the passive optical network operated by the L3 / L2 network according to the present embodiment may include hardware or software mounted on an L3 switch that interoperates with the L3 / L2 network, or on a separate higher level device that interoperates with the L3 / L2 network. It can be implemented as a combination of the two.

As shown in the figure, the subscriber communication failure processing apparatus 100 of the passive optical network operated by the L3 / L2 network according to this embodiment comprises a packet monitoring unit 110 and the control unit 120.

The packet monitoring unit 110 monitors a packet transmitted from an optical network unit (ONU) or an optical network terminal (ONT) 33, that is, an L2 subscriber station and received by the L3 switch 10.

The controller 120 determines that a failure has occurred when the packet having the source address SA is the L3 switch MAC address is received by the packet monitor 110.

That is, a packet normally transmitted from the optical network terminal device (ONU or ONT) 33, which is an L2 subscriber terminal device, to the optical line terminal device (OLT) 31 side, the source address (SA: Source Address) is the L2 subscriber station address, The destination address (DA) has the L3 Mac address, which is the system address.

However, since a looped packet has a source address (SA) of a system address, an L3 MAC address, and a destination address (DA) of an L2 subscriber station, the packet is transmitted from the L2 subscriber station and is transmitted from the L2 switch terminal. 10) monitors the received packet through the packet monitoring unit 110, and if the source address (SA) of the received packet is the L3 switch MAC address, it is determined through the control unit 120.

In this way, in a passive optical network operated by L3 / L2 network, packets transmitted from the L3 switch are looped back from the L2 subscriber station to detect the occurrence of a failure, so that proper handling of the failure can be performed. Can be done.

On the other hand, according to an additional aspect of the present invention, if it is determined that the failure by the control unit 120, by checking the MAC table (MAC Table) of the optical line terminal (OLT) 31, the L3 switch MAC address is It may be implemented to search for learning to find a failed L2 subscriber station, that is, an optical network end device (ONU or ONT) 33.

If the L3 switch MAC address is not learned in the MAC table of the optical line terminal device (OLT), the MAC table of the L2 subscriber station device, that is, the optical network terminal device (ONU or ONT) 33 is not learned. (MAC Table), the L3 switch MAC address can be learned by learning (Learning), it can be implemented to find the L2 subscriber terminal device that has a failure.

Therefore, by doing so, it is possible to know the L2 subscriber station having a failure by searching for the MAC address run in the MAC table, so that appropriate processing for the failure can be made later.

Meanwhile, according to an additional aspect of the present invention, the control unit 120 blocks the communication of the failed L2 subscriber station so that no abnormal packet is transmitted anymore, thereby preventing the packet from being transmitted in the passive optical network operated by the L3 / L2 network. Normal packet drop caused by loop can be eliminated, and service failure can be effectively prevented.

Meanwhile, according to an additional aspect of the present invention, the control unit 120 deletes an incorrectly learned L3 switch MAC address entry from the Mac table to complete an error process, thereby completing a packet. By running the normal MAC table during transmission, it is possible to prevent the failure of the normal packet drop caused by the packet loop in the passive optical network operated by the L3 / L2 network from spreading further. .

On the other hand, according to an additional aspect of the present invention, the control unit 120 may be implemented to output or store the failure processing history after completion of the failure processing. At this time, the failure handling history may be output through the Simple Network Management Protocol (SNMP), which is an application layer protocol defined on TCP / IP for the purpose of monitoring and monitoring the network equipment, and the storage date of the system log. It may be. Thus, the administrator can check the history of the failure processing, thereby enabling more efficient failure management.

A subscriber communication failure processing operation of a subscriber communication failure processing apparatus of a passive optical network operated by an L3 / L2 network according to the present invention having the above configuration will be described with reference to FIG. 4. 4 is a flowchart illustrating a method for processing a subscriber communication failure in a passive optical network operated by an L3 / L2 network according to the present invention.

As shown in the figure, a subscriber communication failure processing apparatus of a passive optical network operating in an L3 / L2 network according to the present invention monitors a packet transmitted from an L2 subscriber station in a packet monitoring step (S110) and received by an L3 switch. do.

Thereafter, when a packet having a source address of L3 switch MAC address is received in the failure determination step (S120), it is determined that a failure has occurred.

In this way, in a passive optical network operated by L3 / L2 network, packets transmitted from the L3 switch are looped back from the L2 subscriber station to detect the occurrence of a failure, so that proper handling of the failure can be performed. It can be done.

According to an additional aspect of the present invention, when the subscriber communication failure processing apparatus of the passive optical network operated by the L3 / L2 network is determined to be a failure by the failure determination step (S120), the optical fiber at the failure location search step (S130) The MAC table of the line terminal device (OLT: Optical Line Termination) may be inspected to search for whether the L3 switch MAC address is learning, and to find an L2 subscriber station having a failure.

At this time, if the L3 switch MAC address is not learning in the MAC table of the optical line terminal device (OLT), the MAC table of the L2 subscriber station device in the fault location search step (S130). Table), the L3 switch MAC address can be searched for learning, and the faulty L2 subscriber station can be found.

Therefore, by doing so, it is possible to know the L2 subscriber station having a failure by searching for the MAC address run in the MAC table, so that appropriate processing for the failure can be made later.

According to an additional aspect of the present invention, a subscriber communication failure processing device of a passive optical network operated by an L3 / L2 network has a failure detected by the failure location search step (S130) in the failure processing step (S140). It is also possible to block the communication of so that no more abnormal packets are transmitted.

Therefore, by doing so, it is possible to solve the normal packet drop caused by the packet loop in the passive optical network operated by the L3 / L2 network, thereby effectively preventing the occurrence of service failure.

At this time, in the fault processing step (S140) by implementing the error processing to complete the failure process by deleting the L3 switch MAC address entry that is learned incorrectly from the Mac table (Mac Table) to run the normal Mac table in the subsequent packet transmission Therefore, it may be possible to prevent the failure of the normal packet drop caused by the packet loop in the passive optical network operated by the L3 / L2 network from being further spread.

According to an additional aspect of the present invention, the subscriber communication failure processing apparatus of a passive optical network operated by L3 / L2 network after the failure processing by the failure processing step (S140) in the history processing step (S150), the failure processing history May be implemented to output or store

At this time, the failure handling history may be output through the Simple Network Management Protocol (SNMP), which is an application layer protocol defined on TCP / IP for the purpose of monitoring and monitoring the network equipment, and the storage date of the system log. It may be. Thus, the administrator can check the history of the failure processing, thereby enabling more efficient failure management.

As described above, the present invention monitors the packet returned from the L2 subscriber station device looped from the L2 subscriber station in the passive optical network operated by the L3 / L2 network to detect a failure occurrence, and furthermore, By blocking the communication of the failed L2 subscriber station equipment so that no abnormal packet is transmitted, the normal packet drop caused by the loop of the packet in the L3 / L2 network is eliminated. It is possible to effectively prevent the occurrence of service failures, it is possible to achieve the object of the present invention presented above.

While the invention has been described with reference to the preferred embodiments, which are referred to by the accompanying drawings, it is apparent that various modifications are possible without departing from the scope of the invention within the scope covered by the following claims from this description. .

Industrial Applicability The present invention can be industrially used in the technical field and its application technology for solving the normal drop of packets due to packet loops in a passive optical network operated by L3 / L2 networks.

1 is a schematic diagram of a passive optical network operating in an L3 / L2 network

FIG. 2 is a diagram illustrating an example of an L2 MAC table in which an L3 MAC address is incorrectly learned.

3 is a block diagram according to an embodiment of a subscriber communication failure processing apparatus of a passive optical network operated by L3 / L2 network according to the present invention;

4 is a flowchart according to an embodiment of a subscriber communication failure processing method of a passive optical network operated by L3 / L2 network according to the present invention.

<Explanation of symbols for the main parts of the drawings>

10: L3 switch 20: L3 network

21: service provider server 30: L2 network

31: Optical line terminal device (OLT) 32: Splitter

33: optical network termination unit (ONU or ONT) 100: communication failure processing unit

110: packet monitoring unit 120: control unit

Claims (12)

A packet monitoring unit for monitoring a packet transmitted from the L2 subscriber station and received by the L3 switch; And A control unit that determines that a failure has occurred when a packet whose source address is an L3 switch MAC address is received by the packet monitoring unit; Apparatus for processing a subscriber communication failure of a passive optical network operated by L3 / L2 network, characterized in that comprises a. The method of claim 1, The control unit: If it is determined that the failure, the MAC table of the optical line terminal (OLT: Optical Line Termination) by examining the L3 switch MAC address learning (Learning), characterized in that to find the failure L2 subscriber terminal device Subscriber communication failure processing device of a passive optical network operated by L3 / L2 network. The method of claim 2, The control unit: If the L3 switch MAC address is not learning in the MAC table of the optical line terminal device (OLT), the MAC table of the L2 subscriber station device is checked and the L3 switch MAC address is set to Learning), and finds the L2 subscriber station that has a failure, the subscriber communication failure processing apparatus of the passive optical network operated by the L3 / L2 network. The method of claim 2 or 3, The control unit: A subscriber communication failure processing apparatus of a passive optical network operated by an L3 / L2 network, characterized in that no more abnormal packets are transmitted by blocking communication of a failed L2 subscriber station. The method of claim 4, wherein The control unit: Apparatus for handling a subscriber communication failure of a passive optical network operated by an L3 / L2 network, characterized in that the failure processing is completed by deleting an L3 switch MAC address entry that is incorrectly learned from the Mac table. The method of claim 5, wherein The control unit: The subscriber communication failure processing apparatus of the passive optical network operated by the L3 / L2 network, characterized in that for outputting or storing the history of failure processing after completion of the failure processing. A packet monitoring step of monitoring a packet transmitted from the L2 subscriber station and received by the L3 switch; And A failure determining step of determining that a failure has occurred when a packet having a source address of the L3 switch MAC address is received; Subscriber communication failure processing method of a passive optical network operated by the L3 / L2 network comprising a. The method of claim 7, wherein If it is determined that the failure is determined by the failure determination step, the MAC table of the optical line termination (OLT: Optical Line Termination) is inspected, the L3 switch MAC address is searched for learning, and the failure occurs. A fault location search step of finding a subscriber station; Subscriber communication failure processing method of a passive optical network operated by the L3 / L2 network characterized in that it further comprises. The method of claim 8, In the fault location search step: If the L3 switch MAC address is not learning in the MAC table of the optical line terminal device (OLT), the MAC table of the L2 subscriber station device is checked and the L3 switch MAC address is set to Learning), the method for processing subscriber communication failure of a passive optical network operated by an L3 / L2 network, characterized in that it further comprises finding a failed L2 subscriber station. The method according to claim 8 or 9, A failure processing step of blocking communication of the L2 subscriber station having a failure detected by the failure location search step so that an abnormal packet is no longer transmitted; Subscriber communication failure processing method of a passive optical network operated by the L3 / L2 network characterized in that it further comprises. The method of claim 10, In the fault handling step: A method for handling subscriber communication failure in a passive optical network operated by an L3 / L2 network, characterized in that a failure processing is completed by deleting an L3 switch MAC address entry that is incorrectly learned from the Mac table. The method of claim 11, A history processing step of outputting or storing a history of failure processing after failure processing is completed by the failure processing step; Subscriber communication failure processing method of a passive optical network operated by L3 / L2 network, characterized in that it further comprises.

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