WO2011011934A1 - Method and apparatus for ethernet tunnel segmentation protection - Google Patents

Abstract

A method for Ethernet tunnel segmentation protection is provided, which includes: a Domain Edge Bridge (DEB) sends connectivity check messages to the opposite end DEB respectively through the primary segment and the backup segment within the protection domains in which the DEB resides to check the status; when the primary segment or the backup segment occupied by the traffic transmission is failed, the protection switching for the traffic is performed. An apparatus for Ethernet tunnel segmentation protection is also provided. Application of the method and the apparatus in the present invention enables the effective segmentation protection for the Ethernet tunnel, protects only the part of segments needing protection, overcomes the shortcoming that the whole Ethernet tunnel needs to be switched when a failure occurs locally in the prior art, and thereby the utilization as well as reliability of the network are improved, the better flexibility is provided in the networking implementation protection, and the requirements of the actual networking are satisfied.

Description

 Ethernet tunnel segmentation protection method and device

Technical field

 The present invention relates to a protection technology for an Ethernet tunnel, and in particular, to an Ethernet tunnel segmentation protection method and apparatus.

Background technique

 With the concept of Carrier Ethernet (CE), the requirements of the telecommunication network are met, and a connection-oriented Ethernet technology (PBT, Provider Backbone Transport) technology is also produced. Subsequently, operators at home and abroad used PBT technology networking to provide a good start for the development of PBT technology in metropolitan area networks.

 PBT technology is a connection-oriented Ethernet transmission technology, also known as Provider Backbone Bridge Traffic Engineering (PBB-TE). The PBB-TE technology is based on the PBB technology. The core of the technology is the improvement of the PBB technology. The source device of the CE is inserted into the destination media access control (MAC) address of the backbone network (B-DA, Backbone Destination MAC Address ), Backbone Source MAC Address of the backbone network, Backbone Virtual Local Area Network Identity (B-VID, Backbone Virtual Local Area Network Identity), and Service Instance Tag (I-TAG, Service) Instance TAG ). The forwarding path between the source device and the destination device of the CE is pre-statically configured. The intermediate CE device can forward the data frame based on the B-DA and B-VID in the forwarding table.

With the concept of carrier-class Ethernet, in order to make Ethernet reach the telecom level standard, higher requirements are placed on the protection and switching of Ethernet. In the existing PBB-TE protection switching technology, the protection of the Traffic Engineering Service Instance (TESI) is supported, that is, an end-to-end tunnel protection, as shown in Figure 1, the end-to-end of a TESI The main tunnel is A^B^C^D^E, A and E represent the end of the tunnel instance; AFGE is the end-to-end backup tunnel of the TESI. This end-to-end protection scheme not only protects the switching time longer, but also involves more nodes and lacks protection for intermediate links and nodes. Once a link or a node in the middle fails, the entire TESI must be switched, and the faulty link or the failed node passes. When there are multiple TESIs, it will cause multiple TESI switches. That is to say, the protection object of the PBB-TE end-to-end protection is TESI. When the TESI of a certain work is detected to be faulty, the user message entering the PBB-TE tunnel needs another header corresponding to the protection TESI. Repackaged to allow traffic to protect the PBB-TE tunnel.

 For Ethernet, link and node protection are part of Ethernet protection. Most network failures occur on a certain link or a node. Therefore, PBB-TE segment protection becomes very necessary, that is, A partial segment of the PBB-TE tunnel needs to be protected to protect a set of traffic engineering service instances passing through the segment. However, the prior art has not been able to provide a more effective PBB-TE segmentation protection scheme, which brings inconvenience to practical applications.

Summary of the invention

 In view of this, the main object of the present invention is to provide an Ethernet tunnel segmentation protection method and apparatus to implement segmentation protection for a PBB-TE tunnel.

 In order to achieve the above object, the technical solution of the present invention is achieved as follows:

 The present invention provides an Ethernet tunnel segmentation protection method, the method comprising:

 The domain border bridge DEB sends a connectivity check message to the peer DEB through the primary and backup segments in the protection domain, and performs state detection.

 When the primary segment or the standby segment occupied by the traffic transmission fails, the protection switching of the traffic is performed.

 Further, before the DEB sends the connectivity check message, the method further includes: configuring a corresponding spare segment for the primary segment, where the primary segment and the spare segment form a closed ring structure to form the protection domain, And the two endpoints shared by the primary segment and the spare segment are the DEBs in the protection domain.

 Further, in the method:

 The step of sending a connectivity check message to the peer DEB further includes: periodically sending a connectivity check message to the peer DEB;

 The steps to perform status detection include:

If the DEB does not receive the connection sent by the peer DEB through the primary segment within a predetermined time If the message is checked, the main segment is determined to be faulty;

 If the DEB does not receive the connectivity check message sent by the peer DEB through the spare segment within a predetermined time, it is determined that the spare segment has failed.

 Further, in the method, the step of performing protection switching on the traffic includes: if the primary segment fails, and the traffic transmission occupies the primary segment, and the spare segment is available, the traffic is Protection is switched to the spare segment;

 If the spare segment sends a failure and the traffic transmission occupies the spare segment while the primary segment is available, the traffic protection is switched to the primary segment.

 Further, in the method:

 The step of switching the traffic protection to the spare segment includes: the DEB changing an egress port of a forwarding table entry corresponding to the traffic stored by itself to a port of the spare segment to which the DEB is connected;

 The step of switching the traffic protection to the primary segment includes: the DEB changing an egress port of a forwarding table entry corresponding to the traffic stored by itself to a port of the primary segment to which the DEB is connected.

 Further, in the method,

 The connectivity check message is a continuity check message CCM message.

 The invention also provides an Ethernet tunnel segment protection device, the device comprising:

 a message sending module, configured to send a connectivity check message to the peer DEB through the primary segment and the spare segment in the protection domain where the DEB is located, respectively, to perform state detection;

 The protection switching module is configured to perform protection switching of the traffic when the primary segment or the spare segment occupied by the traffic transmission fails.

 Further, the device further includes: a configuration module, where the configuration module is configured as a spare segment corresponding to the configuration of the primary segment, wherein the primary segment and the spare segment form a closed annular structure to form the protection domain And the two endpoints shared by the primary segment and the spare segment are the DEBs in the protection domain.

Further, in the device, The message sending module is configured to perform state detection by: if the DEB does not receive the connectivity check message sent by the peer DEB through the primary segment within a predetermined time, determining that the primary segment fails; If the DEB does not receive the connectivity check message sent by the peer DEB through the spare segment within a predetermined time, determining that the spare segment fails;

 The protection switching module is configured to perform protection switching on the traffic by: if the primary segment fails, and traffic transmission occupies the primary segment, and the spare segment is available, The traffic protection is switched to the spare segment; if the spare segment fails, and the traffic transmission occupies the spare segment, and the primary segment is available, the traffic protection is switched to the primary segment.

 Further, in the device,

 The protection switching module is configured to switch the traffic from the primary segment protection to the standby segment by changing the egress port of the forwarding table entry corresponding to the traffic stored by the DEB itself to the DEB connection. The port of the spare segment; and switching the traffic from the spare segment protection to the primary segment by changing the outgoing port of the forwarding table entry corresponding to the traffic stored by the DEB itself to the primary connected to the DEB The port of the segment.

 The connectivity check message is a CCM message.

 The method and device for protecting the segmentation of the Ethernet tunnel provided by the invention effectively implements the segmentation protection of the PBB-TE tunnel, and only protects the segment that needs to be protected, and solves the problem that the prior art local failure needs to be completed. The disadvantages of Ethernet tunnel switching are to improve the utilization and reliability of the network. It has better flexibility in network protection and meets the requirements of actual networking.

BRIEF abstract

 1 is a schematic diagram of an end-to-end protection of PBB-TE in the prior art;

 2 is a flowchart of a method for protecting a segment of an Ethernet tunnel according to the present invention;

3 is a schematic diagram of a topology model for implementing Ethernet tunnel segmentation protection according to the present invention; FIG. 4 is a schematic diagram of topology structure of Ethernet tunnel segmentation protection according to an embodiment of the present invention; FIG. Schematic diagram of the structure of the tunnel segment protection device. Preferred embodiment of the invention

 The technical solutions of the present invention are further elaborated below in conjunction with the accompanying drawings and specific embodiments.

 An Ethernet tunnel segmentation protection method provided by the present invention, as shown in FIG. 2, mainly includes the following steps:

 Step 201: The Domain Edge Bridge (DEB) is configured to implement segmentation protection of the Ethernet tunnel by using the protection thereof. The present invention introduces an intermediate segment protection model, which is an intermediate segment in the PBB-TE network. A set of TESIs on the link (including the link on the segment and the intermediate node on the link) is protected. As shown in FIG. 3, for the part to be protected in the PBB-TE network, there are two paths: a primary segment and a backup segment. The primary segment and the spare segment share two endpoints. Segments and spare segments have different paths. They form a closed loop structure that forms a protective domain. The two endpoints shared by the primary segment and the spare segment are called Domain Border Bridges (DEBs). There may be no intermediate nodes between the DEBs on the primary and secondary segments, or one or more intermediate nodes. For example: DEB includes a series of LANs and intermediate nodes between them.

 The so-called main segment refers to an intermediate segment where the path of the planned data traffic (TESI) is taken when the network is working properly. This segment is protected by the protection domain. The so-called spare segment is a segment that protects the primary segment within its protection domain. As shown in Figure 3, in the absence of a fault, the data traffic is forwarded on the primary segment between B C; when a failure occurs on the primary segment, endpoints B and C switch traffic to the alternate segment.

 TESI is an instance of a MAC service consisting of a set of Ethernet Switch Paths (ESPs). ESP is a one-way Ethernet forwarding path determined by a triple <B-DA, B-SA, 8-¥10>.

The two DEBs (Node B and Node C) in the model send connectivity check messages to the peer DEB through the primary and backup segments, respectively, for link detection. The connectivity check message may be sent periodically or non-periodically. For example: Link detection is performed using the OAM (Operation Administration and Maintenance) mechanism and using the IEEE, Institute of Electrical and Electronics Engineers 802. lag standard. The connectivity check message referred to in the present invention may be, but is not limited to, a continuity check message.

(CCM, Connectivity Check Message).

 Step 202: The DEB performs the protection switching of the traffic when it determines that the primary segment or the standby segment occupied by the traffic transmission is faulty by detecting the status of the primary segment and the standby segment in the protection domain.

 In the model shown in Figure 3, when a DEB (Node B or Node C) does not receive a CCM message sent from the primary segment within a predetermined time, it is considered that a failure occurs on the primary segment, if currently The traffic transmission occupies the primary segment, and when the spare segment is detected, the DEB performs the protection switching operation of the traffic, and the traffic is switched from the primary segment to the spare segment for forwarding. The specific protection switching operation is: DEB The egress port of the forwarding table entry corresponding to the traffic stored by itself is changed to the port of the spare segment to which the DEB is connected, so that the traffic is forwarded according to the new egress port;

 Or, when a DEB does not receive a CCM message sent from the spare segment within a predetermined time, it considers that a failure occurs on the spare segment, if the current traffic transmission occupies an alternate segment, and the primary segment is detected to be available. Then, the DEB performs a protection switching operation of the traffic, and switches the traffic from the standby segment to the primary segment for forwarding. The specific protection switching operation is: DEB changes the egress port of the forwarding table entry corresponding to the traffic stored by the DEB. The port of the primary segment connected to the DEB, so that traffic is forwarded according to the new outgoing port.

 The forwarding table entry that needs to be changed is the <8-0, B-VID> corresponding to a group of TESIs protected by the protection domain; the outgoing port is the primary segment or the spare segment corresponding to the DEB. port.

 The model shown in Figure 3 protects the middle segment of a PBB-TE network that requires a key protection component, and protects the Revertive mode and the Non-Revertive mode. The invention achieves protection of a set of TESIs in a protected domain on a PBB-TE network.

The above Ethernet tunnel segmentation protection method will be described in detail below with reference to the embodiment shown in FIG. As shown in Figure 4, there is a set of TESIs that go through a common part of the path.

共用两个端点 B、 C, 形成保 护域 I； 主用段 D^E^F和备用段 D^H^F共用两个端点 D、 F , 形成保护 域 II。 这两个保护域是相互独立的， 即保护域 I和保护域 II在自身域的内部 进行故障检测，并且其中一个域的切换动作不会对另一个域的行为产生影响。 图 4中的 B、 C、 D、 F节点都是 DEB。 保护域 I和保护域 II可以共用一个端 点， 或中间相隔多个节点。 The main segments B^C and D^E^F are respectively protected, and the corresponding spare segments B^G^C and respectively are configured.

The two endpoints B and C are shared to form a protection domain I; the primary segment D^E^F and the spare segment D^H^F share two endpoints D and F to form a protection domain II. The two protection domains are independent of each other, that is, the protection domain I and the protection domain II perform fault detection inside the domain itself, and the switching action of one domain does not affect the behavior of the other domain. The B, C, D, and F nodes in Figure 4 are all DEBs. Protection domain I and protection domain II can share one endpoint, or multiple nodes in between.

实现保护， B C上传 输主用段的 CCM报文， B^G C上传输备用段的 CCM报文；主用段 D E F 由备用段 D H F实现保护， D E F上传输主用段的 CCM报文， D H F 上传输备用段的 CCM报文。 当检测发现主用段 B C出现故障， 且 TESIs的 传输占用主用段 B^C, 同时检测到备用段 B^G^C可用时， 将 TESIs切换 到备用段

出 现故障， 且 TESIs的传输占用主用段 D^E^F , 同时检测到备用段 D^H^F 可用时， 将 TESIs切换到备用段 D H F上， 反之亦然。 In protection domain I, the primary segment BC is replaced by an alternate segment.

To achieve protection, the CCM message of the main segment is transmitted on the BC, and the CCM message of the spare segment is transmitted on the B^GC; the DEF of the main segment is protected by the DHF of the spare segment, and the CCM message of the main segment is transmitted on the DEF, on the DHF. Transfer the CCM message of the spare segment. When the detection finds that the main segment BC is faulty, and the TESIs transmission occupies the main segment B^C, and detects that the spare segment B^G^C is available, the TESIs are switched to the spare segment.

A fault occurs, and the TESIs transmission occupies the main segment D^E^F, and when the spare segment D^H^F is detected, the TESIs are switched to the spare segment DHF, and vice versa.

 To implement the foregoing Ethernet tunnel segmentation protection method, the present invention also provides an Ethernet tunnel segmentation protection device, which is applied to an Ethernet node (including DEB), as shown in FIG. 5, the device includes : Message sending module 10 and protection switching module 20. The message sending module 10 checks the message and performs fault detection. The protection switching module 20 is configured to perform protection switching on the traffic when the primary segment or the standby segment occupied by the traffic transmission fails.

 Preferably, the device further includes: a configuration module 30, configured to configure a corresponding spare segment for the main segment, the main segment and the spare segment form a closed ring structure to form a protection domain, and the main The two endpoints shared by the segment and the spare segment are the DEBs in the protection domain.

 The protection switching module 20 is further configured to: when the DEB does not receive the connectivity check message sent by the peer DEB through the primary segment within a predetermined time, if the traffic transmission occupies the primary segment and the spare segment is available, the traffic protection is switched to On the spare segment; when the DEB does not receive the connectivity check message sent by the peer DEB through the spare segment within the predetermined time, if the traffic transmission occupies the spare segment and the active segment is available, the traffic protection is switched to the primary segment. The switching operation specifically includes: when the traffic protected by the protected domain needs to be switched from the primary segment protection to the standby segment, the outbound port of the forwarding table entry corresponding to the traffic stored by the DEB itself is changed to the standby segment connected to the DEB. Port: When the traffic protected by the protected domain needs to be switched from the backup segment protection to the primary segment, the egress port entry corresponding to the traffic stored in the DEB itself is changed to the port of the primary segment connected to the DEB.

The above description is only a preferred embodiment of the present invention and is not intended to limit the protection of the present invention. Scope.

Industrial applicability

 Compared with the prior art, the present invention effectively implements the segmentation protection of the PBB-TE tunnel, and only protects the segment that needs to be protected, thereby solving the disadvantages of the entire technology in the prior art that the entire Ethernet tunnel is switched. It improves the utilization and reliability of the network, provides better flexibility in network protection, and meets the requirements of actual networking.

Claims

Claim  1. An Ethernet tunnel segmentation protection method, comprising:  The domain border bridge DEB sends a connectivity check message to the peer DEB through the primary and backup segments in the protection domain, and performs state detection.  When the primary segment or the standby segment occupied by the traffic transmission fails, the protection switching of the traffic is performed.  The Ethernet tunnel segmentation protection method according to claim 1, before the step of transmitting the connectivity check message, the method further includes: configuring the corresponding spare segment for the primary segment, the primary segment And the spare segment constitutes a closed ring structure, forming the protection domain, and the two endpoints shared by the primary segment and the spare segment are DEBs in the protection domain.  The Ethernet tunnel segmentation protection method according to claim 1 or 2, wherein: the step of transmitting a connectivity check message to the peer DEB comprises: periodically transmitting a connectivity check message to the peer DEB;  The steps to perform status detection include:  Determining that the primary segment has failed if the DEB does not receive the connectivity check message sent by the peer DEB through the primary segment within a predetermined time;  If the DEB does not receive the connectivity check message sent by the peer DEB through the spare segment within a predetermined time, it is determined that the spare segment has failed.  The Ethernet tunnel segmentation protection method according to claim 1 or 2 or 3, wherein the step of performing protection switching on the traffic includes:  If the primary segment fails, and the traffic transmission occupies the primary segment, and the spare segment is available, the traffic protection is switched to the spare segment;  If the spare segment sends a failure and the traffic transmission occupies the spare segment while the primary segment is available, the traffic protection is switched to the primary segment.  5. The Ethernet tunnel segmentation protection method according to claim 4, wherein: The step of switching the traffic protection to the spare segment includes: the DEB changing an egress port of a forwarding table entry corresponding to the traffic stored by itself to an alternate segment connected to the DEB Port  The step of switching the traffic protection to the primary segment includes: the DEB changing an egress port of a forwarding table entry corresponding to the traffic stored by itself to a port of the primary segment to which the DEB is connected.  The Ethernet tunnel segmentation protection method according to claim 1 or 2, wherein the connectivity check message is a continuity detection message CCM message.  7. An Ethernet tunnel segmentation protection device, comprising:  a message sending module, configured to send a connectivity check message to the peer DEB through the primary segment and the spare segment in the protection domain where the DEB is located, respectively, to perform state detection;  The protection switching module is configured to perform protection switching of the traffic when the primary segment or the spare segment occupied by the traffic transmission fails.  The Ethernet tunnel segment protection device of claim 7, further comprising: a configuration module, wherein the configuration module is configured as a spare segment corresponding to the configuration of the primary segment, wherein the primary segment and the spare segment The closed loop structure is formed to form the protection domain, and the two endpoints shared by the primary segment and the spare segment are DEBs in the protection domain.  The Ethernet tunnel segment protection device according to claim 7 or 8, wherein  The message sending module is configured to perform state detection by: if the DEB does not receive the connectivity check message sent by the peer DEB through the primary segment within a predetermined time, determining that the primary segment fails; If the DEB does not receive the connectivity check message sent by the peer DEB through the spare segment within a predetermined time, determining that the spare segment fails;  The protection switching module is configured to perform protection switching on the traffic by: if the primary segment fails, and traffic transmission occupies the primary segment, and the spare segment is available, The traffic protection is switched to the spare segment; if the spare segment fails, and the traffic transmission occupies the spare segment, and the primary segment is available, the traffic protection is switched to the primary segment.  10. The Ethernet tunnel segment protection device according to claim 9, wherein The protection switching module is configured to switch the traffic protection to the spare segment by: outputting an egress port of a forwarding table entry corresponding to the traffic stored by the DEB itself Changing to the port of the spare segment to which the DEB is connected; and switching the traffic protection to the primary segment by: outputting an egress port of the forwarding table entry corresponding to the traffic stored by the DEB itself Change to the port of the primary segment to which the DEB is connected.  The Ethernet tunnel segment protection device according to claim 7 or 8, wherein the connectivity check message is a CCM message.