CN101826990A - Method, device and system for detecting connectedness of virtual pseudo wires - Google Patents

Abstract

The embodiment of the invention discloses a method, device and system for detecting virtual pseudowire connectivity, relates to the communication field, and solves the problem in the prior art that the detection speed of PW connectivity cannot meet the requirement of PW switching within 50 ms. In the embodiment of the present invention, in the process of negotiating to establish a PW, the source T-PE sends the parameters including the connectivity of the PW of the MPLA OAM type to the target T-PE. After the PW is established, the target T-PE judges whether the If the MPLS OAM message containing the PW label is received from the source T-PE, if it is judged that the above MPLS OAM message has not been received within the predetermined time, a notification message containing defect information will be constructed; The notification message is sent to the source T-PE. The embodiment of the present invention is mainly applied to the scene of detecting PW connectivity.

Description

Method, device and system for detecting virtual pseudowire connectivity

technical field

The invention relates to the communication field, in particular to a method, device and system for detecting virtual pseudowire connectivity.

Background technique

End-to-end Pseudowire Emulation (PWE3) is to provide a tunnel on a packet switching network (such as a multi-protocol label switching network, namely MPLS network) in order to simulate a virtual private network (VPN) layer 2 protocol for some services. Through this protocol, you can Interconnect the traditional network with the packet switching network, so as to realize the sharing of resources and the expansion of the network.

In the PWE3 technology, the industry defines a connectivity technology for detecting a virtual pseudo wire (PW): virtual circuit connectivity check (VCCV) Ping. VCCV Ping is like a tool to detect the connection status of PW. It verifies the connectivity of PW by defining a series of messages exchanged between the endpoint provider edge routers (T-PE) at both ends. Like LSP Ping for detecting connectivity of Label Switched Path (LSP) tunnels and Internet Control Message Protocol (ICMP) Ping for detecting connectivity of IP networks, it is implemented by extending LSP Ping.

The main process of detecting PW connectivity by extending VCCV Ping of LSP Ping includes:

1. Before the PW is established, that is, during the negotiation process of the T-PEs at both ends, the packets used for negotiation carry the control channel type (CC Types) for the VCCV function. Currently, mainstream applications in the industry generally use type 1, and the connectivity CV Types parameter, currently the mainstream business uses LSP Ping.

2. After the PW is established successfully, start the VCCV Ping function between T-PE1 and T-PE2 to start PW connectivity detection.

3. T-PE1 constructs a VCCV Ping message, and sends the message to the corresponding PW through the LSP1 tunnel, and starts the waiting response timer at the same time. Refer to Figure 1.

Among them, the VCCV Ping message is the extended LSP Ping message carrying forwarding equivalent (FEC) information. The carried FEC information uses Sub-Type=10 "FEC 128" Pseudowire.

4. The virtual pseudowire switching point provider edge router (S-PE) receives the extended LSP Ping message (that is, the VCCV Ping message) and forwards the LSP Ping message to the corresponding PW through the LSP2 tunnel.

5. T-PE2 receives the LSP Ping message.

6. Analyze the information carried in the LSP Ping message, and reply a response message according to the current PW status and the response mode specified by T-PE1. The process also includes filling in other fields of the LSP Ping message, including: serial number, time stamp of message received or sent, response code, response subcode, etc.

7. If T-PE1 receives the response message before the response timer expires, it means that the PW is normal; if the timer times out three times in a row, it means that the PW is faulty.

In the process of detecting PW connectivity through the VCCV Ping message, the format of the VCCV Ping message also changes for different test scenarios, so a unified test format cannot be used, which increases the complexity of the test.

Contents of the invention

Embodiments of the present invention provide a method, device and system for detecting virtual pseudowire connectivity, so as to implement connectivity detection for various PWs.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

A method for detecting virtual pseudowire connectivity, comprising:

negotiating parameters for detecting connectivity of the virtual pseudowire between the first termination and the second termination, the parameters including Multiprotocol Label Switching operation management and maintenance type;

judging on the first termination point whether the MPLS operation management and maintenance message containing the label of the virtual pseudowire is received from the second termination point within a predetermined time;

If it is determined that the MPLS operation management and maintenance message is not received within a predetermined time, constructing a notification message including defect information and a label of the virtual pseudowire;

The notification message is sent to the second termination point through the message channel from the first termination point to the second termination point.

An endpoint that includes:

A negotiation module, for negotiating parameters for detecting the connectivity of the virtual pseudowire between the current termination point and the second termination point, where the parameters include MPLS operation management and maintenance types;

Timer for timing;

A judging module, configured to judge whether an MPLS operation management and maintenance message containing a virtual pseudowire label is received from the second termination point within a predetermined time according to the timing result of the timer;

The notification construction module, if the judging module determines that the MPLS operation management and maintenance message is not received within a predetermined time, then constructs a notification message including defect information and the label of the virtual pseudowire;

A notification sending module, configured to send the notification message to the second termination point through the message channel between the current termination point and the second termination point.

A system for detecting virtual pseudowire connectivity, comprising:

The second termination point sends a negotiation message containing parameters for detecting the connectivity of the virtual pseudowire between the first termination point and the second termination point to the first termination point, where the parameters include multi-protocol label switching operation management and maintenance type, sending an MPLS operation management and maintenance message including the label of the virtual pseudowire to the first termination point;

The first termination point receives the negotiation packet sent by the second termination point, and judges whether the multi-protocol label switching operation management and maintenance packet is received within the predetermined time, and if it is determined that the multi-protocol label switching operation management and maintenance packet is not received within the predetermined time Label switching operation management and maintenance message, constructing a notification message containing defect information and the label of the virtual pseudowire, and sending the notification message through the message channel between the first termination point and the second termination point to the second endpoint.

The method, device and system for detecting virtual pseudowire connectivity provided by the embodiments of the present invention have the following advantages or beneficial effects: Multi-Protocol Label Switching Operation Management and Maintenance (MPLS OAM) message definition is simple, and the existing MPLS OAM message is used Detecting PW connectivity can be said to make the execution process simple; MPLS OAM messages can be used in milliseconds to realize fast detection of PW connectivity; in addition, many mainstream products in the industry have already implemented MPLS OAM in hardware, which is convenient for the implementation of the present invention Example for faster deployment of the function of quickly detecting PW connectivity through MPLS OAM packets.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is the schematic diagram of the scene that detects virtual pseudowire connectivity by LSP Ping in the background technology;

FIG. 2 is a flowchart of a method for detecting virtual pseudowire connectivity according to Embodiment 1 of the present invention;

3 is a schematic diagram of a scene of detecting virtual pseudowire connectivity according to Embodiment 2 of the present invention;

4 is a flowchart of a method for detecting virtual pseudowire connectivity according to Embodiment 2 of the present invention;

5 is a block diagram of a device on the target side for detecting virtual pseudowire connectivity according to Embodiment 3 of the present invention;

6 is a block diagram of an apparatus for detecting virtual pseudowire connectivity according to Embodiment 4 of the present invention;

FIG. 7 is a block diagram of a system for detecting virtual pseudowire connectivity according to Embodiment 5 of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Example 1

This embodiment discloses a method for detecting virtual pseudowire connectivity, as shown in Figure 2, the method includes the following steps:

101. The source T-PE sends a request message, requesting to establish a PW with the peer T-PE (that is, the target T-PE).

102. The target T-PE receives the request message sent from the source T-PE.

After negotiation between the source T-PE and the target T-PE, a PW from the source T-PE to the target T-PE is established.

103. The source T-PE and the target T-PE start the VCCV Ping function respectively.

104. The source T-PE sends the MPLS OAM message carrying the label of the PW to the target T-PE through the established PW.

105. The target T-PE judges whether it has received the MPLS OAM message sent from the source T-PE within the predetermined time. If it receives the MPLS OAM message containing the label of the PW within the specified time, it means that the source T-PE If the PW from the PE to the target T-PE is connected, execute step 106, otherwise continue to execute this step to monitor the connectivity of the PW. If the MPLS OAM report sent from the source T-PE is not received within the predetermined time text, it means that the PW from the source T-PE to the target T-PE is unreachable, go to step 106.

106. Construct a notification message according to the current PW status, where the notification message includes defect information corresponding to the current PW status type.

107. Send a notification message containing defect information corresponding to the current PW state type to the source T-PE through the message channel bundled with the PW. Since it is from the destination T-PE to the source T-PE, therefore, It can also be called a reverse channel. The reverse channel may be a dedicated PW from the target T-PE to the source T-PE, or a shared PW from the target T-PE to the source T-PE, or may be a separate out-of-band channel.

The method for detecting virtual pseudo-wire connectivity provided by this embodiment solves the problem of existing problems by adding a PW label to an MPLS OAM message that can be quickly detected, and detecting PW connectivity through the MPLS OAM message. There is a technical problem that PW connectivity cannot be quickly detected in the technology. If the detection time length, that is, the predetermined time, is set within 50ms, the technical effect of PW switching within 50ms can be achieved.

Example 2

This embodiment specifically describes a method for detecting virtual pseudowire connectivity in combination with the scene in FIG. 3 .

Among them, T-PE1 is the source T-PE that implements MPLS OAM initiation and establishment of PW through hardware, the switching point provider edge router (S-PE) is an intermediate forwarding router, and T-PE2 is the receiving request for MPLS OAM implementation through hardware Establish the target T-PE end of the PW. Those skilled in the art can know that T-PE2 can also be used as the source T-PE end that initiates the establishment of the PW, and T-PE1 is the target T-PE end that receives the request to establish the PW. The PW and the method of performing connectivity detection on the established PW are consistent with T-PE1 as the source T-PE end and T-PE2 as the target T-PE end.

As shown in Figure 4, the method includes:

301. T-PE1 sends a PW establishment request packet to T-PE2, that is, requests to establish a PW from T-PE1 to T-PE2.

302. The S-PE receives the request message and sends it to T-PE2.

303. T-PE2 receives the request packet sent by T-PE1.

304. T-PE1 sends a negotiation message to T-PE2. The negotiation message carries CC parameters and CV parameters for the VCCV Ping function. The negotiation message may also carry the number of MPLS OAM messages and/or a timer timing cycle, etc. Among them, the CV parameter includes the MPLS OAM type.

The CC parameters carried in the above negotiation message are CC Types, which in this embodiment are:

0x01 Type 1: PWE3 control word with 0x0001 as first nibble

0x02 Type 2: MPLS Router Alert Label

0x04 Type 3: MPLS inner label TTL＝1

Type 1: PWE3 control word mode in which the first 4 bits start with 0001b;

Type 2: MPLS routing alarm label;

Type 3: TTL carried in the MPLS PW label = 1;

At present, mainstream applications in the industry generally use type 1, and in this embodiment, the network management side presets the highest priority to use type 1.

The CV parameter is the CV Type, which in this embodiment is:

0x01 ICMP Ping

0x02 LSP Ping

0x04 MPLS OAM

In this embodiment, the network management side pre-sets the highest priority to use the MPLS OAM type in the CV parameter as the detection means adopted by T-PE1 and T-PE2 when subsequent PW detection is performed.

The negotiation message also carries the number of MPLS OAM packets sent by T-PE1 and/or the timing period of the T-PE2 timer, wherein the number of MPLS OAM packets*timing period is preferably less than or equal to a predetermined time, and the predetermined time can be determined according to the system The detection time is required to be determined, for example, the predetermined time is specified as 50 ms.

After the above negotiation process, the negotiated PW is established between T-PE1 and T-PE2.

305. For the PW, T-PE1 and T-PE2 start the VCCV Ping function respectively.

T-PE2 starts the timer, and the timer will restart after each time-out, where the timer time-out means the end of a timing period of the timer.

306. The hardware processing module of T-PE1 that supports MPLS OAM message processing constructs a Fast Defect Detection (FFD) message according to the instructions of the host software module (FFD message is a type in the MPLS OAM message), and puts it in the Frequency field Specify the sending frequency or detection time length of the FFD packet in . The reciprocal of the sending frequency of the FFD message is the detection period for detecting the PW connectivity. In this embodiment, the detection time length is set as the timing period of the timer at the T-PE2 end.

The data structure of the FFD message is as follows:

0 7 31

The meanings corresponding to the fields in the above FFD message are as follows:

field length describe Function type 1 byte Message type, 0x07 represents FFD message. Reserved 3 bytes reserved text. LSP Trail Termination Source Identifier 20 bytes TTSI, the unique identifier of the PW in the network. It consists of 16-byte Sender's PE Address and 4-byte PW ID. For IPv4, the first 10 bytes of Sender’s PE Address are filled with 0x00, the middle 2 bytes are filled with 0xFF, and the last 4 bytes are IPv4 addresses. Frequency 1 byte FFD packet sending frequency. Padding 17 bytes Populate the fields. BIP16 2 bytes Packet checksum.

In this embodiment, the sending frequency of the FFD message is once every 10 ms.

The hardware processing module of T-PE1 that supports MPLS OAM message processing encapsulates a data structure containing the label of the PW on the basis of the above FFD message according to the instructions of the host software module, so as to obtain the above FFD message and PW label Messages with other information, such as MPLS OAM messages containing information such as the above-mentioned FFD message and PW label.

In this embodiment, the data structure of the message containing information such as the above-mentioned FFD message and PW label is as follows:

The data structure of the message containing the information such as the above FFD message and PW label, and the description of each field is as follows:

name bit width bits) describe dmac 48 Destination mac address smac 48 source mac address tpid 16 Type field (0x8100 represents virtual local area network) cfi 1 When the CFI (Canonical Format Indicator) field takes a value of 1, it means that it supports E_RIF (Embedded Source) up 3 user priority vlanid 12 Virtual LAN number ethtype 16 Ethernet message protocol type, 0x8847 is MPLS unicast message label1 20 Label ID, tunnel label, used to make forwarding decisions. exp1 3 Experimental domain, usually used as a quality of service (QoS) flag s1 1 The bottom of the stack flag field, 0 means not at the bottom of the stack sabel2 20 Label ID, the label of the PW, used to determine the access link (AC) exp2 3 Experimental domain, usually used as a QoS flag s2 1 The bottom of the stack flag field, 0 means not at the bottom of the stack sabel3 20 Label ID, where 14 means MPLS OAM message exp3 3 Experimental domain, usually used as a QoS flag s3 1 Stack bottom flag field, 1 means stack bottom, internal data is MPLS OAM mpls oam payload m*8 MPLS OAM packet payload data fcs 32 Check Digit

Wherein, the FFD message may be in a certain field of the data structure, such as the mpls oam payload field. The label2 included in the data structure of the message including the FFD message and the PW label and other information is the label of the PW, and the FFD message is carried on the PW through the label2.

T-PE1 specifies that the target of the FFD message is T-PE2, and sends the FFD message through the PW established through negotiation, and the FFD message includes the label of the PW.

T-PE1 starts a timer, and according to the number of MPLS OAM packets determined after negotiation with T-PE2 and the timing period of the timer, cyclically sends the above-constructed packets containing information such as FFD packets and PW labels. The sending frequency of the FFD message corresponds to the time of the timer, and the timer will be restarted after timeout.

The sequence of sending the FFD message and starting the timer is not limited to the sequence described in this embodiment, and the two processes can even be executed simultaneously.

307. The S-PE receives the FFD packet including the PW label sent from T-PE1, and sends the FFD packet to T-PE2 through the PW corresponding to the PW label.

308. T-PE2 receives the FFD packet containing the label of the PW. The hardware forwarding engine of T-PE2 determines that the received packet is an MPLS OAM packet according to the CC type and the value of Label3 in the negotiation process. According to the PW The label of the corresponding PW is determined.

The hardware forwarding engine of T-PE2 reports the MPLS OAM message (that is, the FFD message) to the hardware processing module that supports the processing of the MPLS OAM message.

The hardware processing module of T-PE2 that supports MPLS OAM message processing compares the type of MPLS OAM message reported by the hardware forwarding engine (that is, FFD), frequency (that is, an FFD message is sent every 10ms), TTSI and other information with the locally recorded The received corresponding values are compared to determine whether the message is correct, and the number of correct messages and error messages received within the detection period is counted, and step 309 is executed.

If do not receive this MPLS OAM message, then judge when receiving the FFD message of this label that contains PW, whether timer overtimes three times, if judge overtime three times, then execute step 309; Otherwise return execution step 308.

The timer of T-PE2 can be started for the first time after the negotiation with T-PE1 is completed, or it can be started for the first time after receiving the first MPLS OAM message. According to the content of the negotiation, the number of messages received by T-PE2 * timing period Preferably, it is less than or equal to a predetermined time, and the predetermined time can be determined according to the detection time requirement of the system, such as 50 ms.

309. T-PE2 constructs a Defect Notification (BDI) message according to the current PW status (the BDI message is a type of MPLS OAM message), and the BDI message includes the parameter type corresponding to the current PW status .

The data structure of the BDI message is as follows:

0 7 15 31

Corresponding to the data structure of the above BDI message, the meaning of each field is as follows:

field length describe Function type 1 byte Message type, 0x02 represents FDI message. Reserved 1 byte reserved text. Defect type 2 bytes LSP defect type. field length describe TTSI 20 bytes TTSI, the unique identifier of the PW in the network. It consists of 16 bytes of Sender's PEAddress and 4 bytes of PWID. For IPv4, the first 10 bytes of Sender’sPEAddress are filled with 0x00, the middle 2 bytes are filled with 0xFF, and the last 4 bytes are IPv4 addresses; if TTSI is not used, this field is filled with 0x00. Defect location 4 bytes Defect location information. Padding 14 bytes Populate the fields. BIP16 2 bytes Packet checksum.

Among them, the field Defect location is used to record the location information of the defect on the virtual pseudo-wire.

Send the constructed BDI message to T-PE1 through the message channel bound with the PW. The message channel may be a dedicated PW from T-PE2 to T-PE1, or a shared PW from T-PE2 to T-PE1, or a separate out-of-band channel.

310. The S-PE receives the BDI message and sends it to T-PE1.

311. T-PE1 receives the BDI packet sent by T-PE2, and obtains defect information in the packet.

T-PE 1 performs operations such as active-standby PW switching, and notifies the peer T-PE2 of the PW switching by sending a Notification message.

In this embodiment, the S-PE is an optional device. In another embodiment of the present invention, the PW established from T-PE1 to T-PE2 is a logical direct connection, so there is no need to go through the S-PE. In another embodiment of the present invention, the method for detecting virtual pseudowire connectivity includes: 301, 303 to 306, 308, 309, 311 in this embodiment. (That is, the steps of forwarding through the S-PE are reduced, but the steps of the method for detecting PW connectivity remain unchanged).

Generally, when T-PE1 sends a request packet to negotiate with T-PE2 to establish a PW from T-PE1 to T-PE2, T-PE2 also sends a request packet to negotiate with T-PE1 to establish a PW from T-PE2 to T-PE2. For PW1 in the direction of T-PE1, the process of establishing PW1 and the process of detecting the connectivity of PW1 through MPLS OAM messages are the same as the process of establishing PW from T-PE1 to T-PE2 in the direction described in this embodiment and the process of establishing PW through MPLS OAM messages. The process of detecting the connectivity of the PW is similar to that described above. At this time, T-PE2 is the source T-PE of the initiator, and T-PE1 is the target T-PE of the receiver accordingly.

In addition, the FFD message used to detect the connectivity of the established PW in this implementation can also be replaced by a connectivity detection (CV) message, and the method steps performed by it are the same as those described in this embodiment using the FFD message. resemblance.

The data structure of the CV message is as follows:

0 7 7 31

Corresponding to the above CV message, the meaning of each field is as follows:

field length describe Function type 1 byte Message type, 0x01 represents CV message. Reserved 3 bytes reserved text. LSP Trail Termination Source Identifier 20 bytes TTSI, the unique identifier of the PW in the network. It consists of 16-byte Sender'sPE Address and 4-byte PW ID. For IPv4, the first 10 bytes of Sender’s PE Address are filled with 0x00, the middle 2 bytes are filled with 0xFF, and the last 4 bytes are IPv4 addresses. field length describe Padding 18 bytes Populate the fields. BIP16 2 bytes Packet checksum.

In addition, it should be noted that if the negotiated PW still has the protection of the outer LSP tunnel, the frequency of sending FFD packets to detect the connectivity of the PW, that is, the detection period should preferably be greater than the detection period of the outer LSP tunnel. The protection of the layer LSP tunnel will not take effect. Correspondingly, for the timers of T-PE1 and T-PE2, the timing period is also preferably set to be greater than the detection period of the outer layer LSP tunnel.

The FFD message in MPLS OAM has the function of setting the sending frequency, so by adjusting the sending frequency of the FFD message, various settings for the PW detection cycle can be realized, and because the FFD message The sending frequency can be in milliseconds, so detecting PW connectivity through FFD messages can realize fast detection and meet the requirements of PW active/standby switchover within 50 ms required by telecom reliability. The method for detecting virtual pseudowire connectivity described in this embodiment adopts the technique of adding the MPLSOAM type in the CV parameter, and including the label of the detected PW and the FFD message corresponding to each detected PW in the MPLS OAM The method solves the technical problem that the PW connectivity detection in the prior art cannot meet the requirements of telecommunication reliability, and then achieves the rapid detection of the PW connectivity, and reasonably sets the sending frequency of the FFD message sent by the host software module , the hardware processing module that supports MPLS OAM message processing performs MPLS OAM message encapsulation of PW label and other information to meet the requirements of telecom reliability, such as setting the sending frequency of the host software module to send FFD messages every 10ms Or sending once every 15ms can meet the beneficial effect of PW active-standby switchover within 50ms required by telecom reliability. Here, the hardware processing speed is fast and the processing delay is negligible. At the same time, because many mainstream products in the industry have implemented hardware MPLS OAM, the embodiment of the present invention can more quickly and conveniently deploy the function of implementing PW connectivity detection through hardware MPLS OAM.

Example 3

In order to facilitate the implementation of the method for detecting the connectivity of a virtual pseudowire in Implementation 1, this embodiment discloses a device for detecting the connectivity of a virtual pseudowire, which is suitable for deployment on a target T-PE, as shown in FIG. 5 , It includes: a detection receiving module 24 , a judgment module 25 , a notification construction module 26 , and a notification sending module 27 .

The detection and receiving module 24 is used to receive the MPLS OAM message sent from the source T-PE, and the MPLS OAM message includes the label of the established PW; the judging module 25 is used to judge whether to detect and receive the PW within a predetermined time after the PW is established. Whether the module 24 has received the MPLS OAM message, and the label of the PW is included in the MPLS OAM message; when the judging module 24 judges that the MPLSOAM message is not received within the predetermined time, the notification construction module 26 constructs a notification that includes defect information Message; the notification sending module 27 is configured to send the notification message containing defect information to the source T-PE through a message channel after the construction module 26 constructs the notification message.

The above device can also be used at the source T-PE end, and in this case, the device further includes: a detection and sending module.

After the virtual pseudowire is established, VCCV Ping is started, and the detection and sending module is used to send the MPLS OAM message to the target T-PE through the established PW, and the MPLS OAM contains the PW label corresponding to the PW.

The solution provided by this embodiment solves the problem by adopting the technical solution of adding the MPLS OAM type in the process of establishing a PW, and judging whether the MPLS OAM message containing the label of the PW is received within a predetermined time after the PW is established. In the prior art, there is a technical problem that the PW connectivity cannot be detected at a speed that meets the requirements of telecommunication reliability, and the technical effect that the MPLS OAM message can be used to quickly detect the PW connectivity and meet the PW switching within 50ms has been achieved.

Example 4

Corresponding to the method in Implementation 2, this embodiment provides a device for detecting virtual pseudowire connectivity, as shown in FIG. A receiving module 45 and a switching module 46 .

The negotiation sending module 41 is used to send the negotiation message of setting up PW to the target T-PE, and the CV parameter of the negotiation message includes the MPLS OAM type; the construction module 42 is used to construct the MPLS OAM report comprising the label of the PW text; the detection sending module 43 is used to send the MPLS OAM message to the target T-PE through the established PW after the PW is set up, and the MPLS OAM message includes the label of the PW; the timer 44 is used to calculate and send The module sends the time of MPLS OAM, restarts after this timer expires; Notification receiving module 45 is used for receiving the BDI message that contains defect information; switch.

The detection sending module 43 in this embodiment is also used to send the MPLS OAM message to the target T-PE through the successfully established PW with the period of the sending timer started by the starting module 44 as a period. In addition, the MPLS OAM message sent by the detection sending module 43 may be forwarded by at least one S-PE to reach the target T-PE, or may be directly sent to the target T-PE without being forwarded by the S-PE. The MPLS OAM message sent by the detection sending module 43 is specifically the FFD message in the MPLS OAM.

The device including the negotiation sending module 41, the construction module 42, the detection sending module 43, the timer 44, the announcement receiving module 45 and the switching module 46 is applied to the source T-PE.

When the source T-PE is the source T-PE that realizes MPLS OAM by hardware, the construction module 42 is a hardware processing module that supports MPLS OAM message processing; Indicates to construct an MPLS OAM packet containing the label of the PW.

This embodiment also provides a device, which is a target T-PE, as shown in Figure 6, including: a negotiation receiving module 47, a timer 414, a starting module 411, a detection receiving module 40, a judging module 48, and a notification structure Module 49, notification sending module 410, reporting module 412, hardware processing module 413 supporting MPLS OAM message processing.

The negotiation receiving module 47 is used to receive the negotiation message of setting up PW sent from source T-PE, and the CV type parameter of described negotiation message includes MPLS OAM type; After PW is set up, timer 414 starts, and this timer uses When calculating the time when receiving the MPLS OAM message, the timer will restart after overtime; the detection receiving module 41 is used to receive the MPLS OAM message containing the label of the PW sent from the source T-PE; the judging module 48 uses To judge whether to receive the MPLS OAM message within the predetermined time, the MPLS OAM message includes the label of the PW; The MPLS OAM message of the label of PW; Then the notification construction module 49 constructs the notification message containing the defect information; the notification sending module 410 is used to send the notification message containing the defect information to the source T-PE through the reverse channel.

When the target T-PE is a target T-PE that implements MPLS OAM through hardware, the reporting module 412 is used to report the MPLS OAM message received by the detection receiving module 40 to its hardware forwarding engine that supports MPLS OAM message processing A hardware processing module 413; the hardware processing module 413 supporting MPLS OAM message processing is used to process the MPLS OAM message reported by the reporting module 412.

The MPLS OAM message that detection receiving module 40 receives can arrive at target T-PE after the forwarding of at least one S-PE; Described MPLS OAM message is specifically the FFD message in MPLS OAM; Notification construction module 49 The constructed notification message is specifically a BDI message in MPLS OAM, and the reverse channel passed by the notification sending module 410 can be a dedicated reverse PW, a shared reverse PW, or a separate out-of-band channel .

The judging module 48 and the reporting module 412 in this embodiment do not limit the order of execution, and may even be executed at the same time.

In addition, in another embodiment of the present invention, when receiving MPLS OAM message, timer 414 starts, and this timer is used for calculating the time of receiving described MPLS OAM message, restarts after this timer expires; When the timer continuously expires for a predetermined number of times, the judging module 48 judges that the MPLS OAM message containing the label of the PW has not been received within the predetermined time.

The device for detecting virtual pseudowire connectivity provided by the embodiment can be implemented by software or by hardware. In particular, since the current mainstream products in the industry have implemented hardware MPLS OAM, the detection of virtual pseudowire provided by this embodiment It will be more convenient and faster to implement the connectivity device through hardware, and compared with the software implementation method, the hardware implementation will better reflect the function of quickly detecting the PW connectivity.

Example 5

This embodiment discloses a system for detecting virtual pseudowire connectivity. As shown in FIG. 7 , the system includes: a source T-PE91, a target T-PE92, and an S-PE93.

The source T-PE91 is used to send the MPLS OAM message to the target T-PE92 through the established PW after the PW is established, and the MPLS OAM message contains the label of the PW; the S-PE93 is used to receive the - PE91 sends the message, and forwards the message to the target T-PE21; the target T-PE92 is used to determine whether the MPLS OAM message is received within the predetermined time after the PW is established, and the MPLS OAM message Containing the label of the PW, if it is determined that the MPLS OAM message is not received within the predetermined time, construct a BDI message containing the defect information, and send the BDI message containing the defect information to the source T through the reverse channel -PE91.

In the process of negotiating to establish a PW, the source T-PE91 is also used to send a negotiation message for establishing a PW to the target T-PE92, and the CV parameter of the negotiation message includes the MPLS OAM type; correspondingly, the target T-PE92 also It is used to receive the above-mentioned negotiation message for establishing a PW sent from the source T-PE91.

The MPLS OAM message sent by the source T-PE91 in this embodiment reaches the target T-PE92 through at least one S-PE93 forwarding; Certainly, this S-PE93 is optional equipment, in another embodiment of the present invention The MPLS OAM message sent by the source T-PE91 does not need to be forwarded by the S-PE93 device, but directly reaches the target T-PE92.

When both the source T-PE91 and the target T-PE92 are T-PEs that implement MPLS OAM through hardware, the source T-PE91 in this embodiment constructs the MPLS OAM message containing the label of the PW as the hardware forwarding engine The hardware processing module supporting MPLS OAM message processing is constructed according to the instructions of its host software module. Correspondingly, the target T-PE92 is also used to report the MPLS OAM message to the hardware processing module supporting MPLS OAM message processing of its hardware forwarding engine, and through the hardware processing module supporting MPLS OAM message processing to The MPLS OAM message is processed.

In addition, the target T-PE92 is also used to start a receiving timer, which is restarted after the receiving timer expires, and when the receiving timer continuously times out for a predetermined number of times, it is determined that the MPLS operation management has not been received within the predetermined time. and maintenance messages; or the target T-PE92 is also configured to start a first receiving timer when receiving an MPLS operation management and maintenance message, restart the first receiving timer after timeout, and when the When the first receiving timer expires continuously for a predetermined number of times, it is determined that the MPLS operation management and maintenance message has not been received within the predetermined time.

The MPLS OAM message sent by the source T-PE91 is specifically the FFD message in the MPLS OAM; the notification message constructed by the target T-PE92 is specifically the BDI message in the MPLS OAM; the reverse channel can be a dedicated reverse PW, a shared The reverse PW can also be a separate out-of-band channel.

The embodiment of the present invention is mainly used in the communication field. In the PWE3 technology in the field, if the hardware forwarding engine where PWE3 is located implements the hardware bidirectional forwarding detection (BFD) function, the embodiment of the present invention can also be used for BFD to quickly detect PW connectivity. neutral. Of course, with the development of communication technologies, the embodiments of the present invention may be applied to other scenarios in this field, and may also be transferred to similar or similar technical fields.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware, but in many cases the former is a better implementation Way. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product is stored in a readable storage medium, such as a floppy disk of a computer , a hard disk or an optical disk, etc., including several instructions for enabling a router to execute the methods described in various embodiments of the present invention.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (11)

1. a method that detects connectedness of virtual pseudo wires is characterized in that, comprising:

Negotiation is used to detect the parameter of the connectedness of the virtual pseudo wires between first destination node and second destination node, and described parameter comprises multiprotocol label switching Operation, Administration and Maintenance type;

On first destination node, judge the multiprotocol label switching Operation, Administration and Maintenance message that whether receives in the given time from the label that comprises described virtual pseudo wires of second destination node;

If judge not receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time, then structure comprises the notification packet of the label of defect information and described virtual pseudo wires;

To the message channel of second destination node described notification packet is sent to second destination node by first destination node.

2. the method for detection connectedness of virtual pseudo wires according to claim 1 is characterized in that, described parameter also comprises: second destination node periodically sends the timing cycle of multiprotocol label switching Operation, Administration and Maintenance message to first destination node;

Described method also comprises: utilize described timing cycle to dispose the timer of the detection of connectivity that is used for the virtual pseudo wires between first destination node and second destination node on first destination node.

3. the method for detection connectedness of virtual pseudo wires according to claim 2 is characterized in that, described parameter also comprises: second destination node sends the number of multiprotocol label switching Operation, Administration and Maintenance message to first destination node.

4. the method for detection connectedness of virtual pseudo wires according to claim 1 is characterized in that timer disposes timing cycle;

Describedly judge that on first destination node multiprotocol label switching Operation, Administration and Maintenance message whether receive in the given time from the label that comprises described virtual pseudo wires of second destination node comprises:

When the continuous overtime pre-determined number of described timer, then judge not receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time.

5. the method for detection connectedness of virtual pseudo wires according to claim 1 is characterized in that, described message channel comprises the pseudo-line of particular virtual, shares virtual pseudo wires or independent out-band channel.

6. according to the method for each described detection connectedness of virtual pseudo wires of claim 1 to 5, it is characterized in that,

When receiving described multiprotocol label switching Operation, Administration and Maintenance message, start the timer on described first destination node first; Or

After finishing, negotiation starts the timer on described first destination node first.

7. the method for detection connectedness of virtual pseudo wires according to claim 4 is characterized in that, if there is the outer layer label switching path in described virtual pseudo wires, the timing cycle of described timer is set to greater than outer layer label switching path timing cycle.

8. according to the method for each described detection connectedness of virtual pseudo wires of claim 1 to 5, it is characterized in that described defect information comprises defect location information.

9. a destination node is characterized in that, comprising:

Negotiation module consults to be used to detect the parameter of the connectedness of the virtual pseudo wires between this destination node and second destination node, and described parameter comprises multiprotocol label switching Operation, Administration and Maintenance type;

Timer is used for timing;

Judge module is used for judging the multiprotocol label switching Operation, Administration and Maintenance message that whether receives in the given time from the label that comprises virtual pseudo wires of second destination node according to the timing result of timer;

The announcement constructing module does not receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time if judge module is judged, then structure comprises the notification packet of the label of defect information and described virtual pseudo wires;

The announcement sending module is used for by the message channel between this destination node and second destination node described notification packet being sent described second destination node.

10. destination node according to claim 9 is characterized in that, when described judge module reaches pre-determined number at the continuous expired times of timer, judges not receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time.

11. a system that detects connectedness of virtual pseudo wires is characterized in that, comprising:

Second destination node, send the negotiation packet of the parameter comprise the connectedness that is used to detect the virtual pseudo wires between first destination node and second destination node to first destination node, described parameter comprises multiprotocol label switching Operation, Administration and Maintenance type, sends the multiprotocol label switching Operation, Administration and Maintenance message of the label that comprises described virtual pseudo wires to first destination node;

First destination node, receive the negotiation packet that second destination node sends, judge whether receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time, do not receive described multiprotocol label switching Operation, Administration and Maintenance message in the given time if judge, then structure comprises the notification packet of the label of defect information and described virtual pseudo wires, and by the message channel between first destination node and second destination node described notification packet is sent to second destination node.

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