CN102404171A - Method and device for detecting Ethernet links - Google Patents
Method and device for detecting Ethernet links Download PDFInfo
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- CN102404171A CN102404171A CN2011103787176A CN201110378717A CN102404171A CN 102404171 A CN102404171 A CN 102404171A CN 2011103787176 A CN2011103787176 A CN 2011103787176A CN 201110378717 A CN201110378717 A CN 201110378717A CN 102404171 A CN102404171 A CN 102404171A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/08—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
- H04L43/0805—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability
- H04L43/0811—Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters by checking availability by checking connectivity
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/46—Interconnection of networks
- H04L12/4604—LAN interconnection over a backbone network, e.g. Internet, Frame Relay
- H04L12/462—LAN interconnection over a bridge based backbone
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/10—Active monitoring, e.g. heartbeat, ping or trace-route
Abstract
The invention discloses a method and a device for detecting Ethernet links. The method comprises the following steps: transmitting a detection message to a source node; judging whether the node is a destination node after receiving a node of the detection message; if so, generating a response message and feeding back to the source node, if not, transmitting the detection message to the next hop node of a detection link; and displaying the detection result for users by the source node according to the received response message. The invention reduces the workload of detection equipment.
Description
Technical field
The present invention relates to the Ethernet field of the communication technology, relate in particular to a kind of ethernet link detection method and device.
Background technology
Develop rapidly along with ethernet technology; The proportion of Ethernet networking in networking increases gradually; The network size of Ethernet also constantly enlarges; From inserting, converging to backbone network and all used Ethernet to replace the ATM network equipments such as (Asynchronous Transfer Mode, asynchronous transfer modes) in a large number.
Traditional Ethernet does not have the carrier class managerial ability; Can not detect, announce or isolate the double layer network fault; And the webmaster that adopts SNMP (Simple Network Management Protocol, Simple Network Management Protocol) agreement also can only link management and equipment state, can not detect the end-to-end switching performance and the state of customer service; When network breaks down, can't locate or locate rapid inadequately.And the extensive application of the network equipment, the network device management person pays close attention to OAM (Operation, Administration, Maintenance, operation, management, the maintenance) function of ethernet device more.
At present, existing Ethernet OAM agreement comprises 802.3ah, 802.1ag, agreements such as ITU-Y1731.
802.1ag propose, mainly be to other management of " service " level, for network provides easily and the function of fault discovery, detection and management efficiently by IEEE.Can be effectively to virtual bridge local area network (LAN) check, isolation and connectivity fault report, be ETHOAM standard end to end.
802.1ag CFM (Connectivity Fault Management, be communicated with mismanage) agreement through loopback and the connectedness of linktrace dual mode according to demand detection end-to-end link.Use loopback to detect the connectedness of link,, then can't confirm the position of being out of order and taking place if the link that detects has fault; Use linktrace to detect the connectedness of link; Each intermediate node (MIP (Maintenance association Intermediate Point; Maintenance Intermediate Point) or MEP (Maintenance association End Point, maintaining end point)) all to return the answer message to the promoter (MEP) of link detecting, notify MAC (the Media Access Control of its this interface; Medium access control) address; Simultaneously detection messages is forwarded, be 1 or find purpose MP (Maintenance Point, maintenance point) up to ttl.The method of this detection link failure has increased the workload of link intermediate node, and simultaneously, link detecting promoter need handle the answer message that each intermediate node returns, and the MAC Address of record intermediate node, has increased link detecting promoter's workload.
Summary of the invention
The objective of the invention is, a kind of ethernet link detection method and device are provided, to reduce the workload of checkout equipment.
The invention provides a kind of ethernet link detection method, said method is:
Source node sends detection messages;
Receive the node of above-mentioned detection messages judges whether this node is destination node, if, then generate and reply message and return to above-mentioned source node, otherwise, above-mentioned detection messages is sent to the next-hop node that detects link;
Above-mentioned source node shows the link detecting result according to the answer message of receiving to the user.
The present invention also provides a kind of ethernet link checkout gear, and said apparatus comprises packet sending and receiving module, judge module and display module,
The packet sending and receiving module is used to receive and dispatch detection messages and replys message; And when receiving that detection messages and above-mentioned judge module are judged this node and be destination node, generate and reply message and also send to source node; And when above-mentioned judge module is judged this node and is not destination node, above-mentioned detection messages is sent to the next-hop node that detects link;
Judge module is used for the detection messages received according to above-mentioned detection messages transceiver module, judges whether this node is destination node;
Display module is used for the answer message received according to above-mentioned detection messages transceiver module, shows the link detecting result to the user.
Among the present invention; The detection messages that intermediate node on the detection link only need be received forwards and gets final product; No longer need return the answer message to the initiation node-source node of link detecting; Have only destination node just to return the answer message, not only reduced source node and handled the quantity of replying message, and do not needed buffer memory to reply message to source node; Simultaneously, also reduced the workload of intermediate node.
Description of drawings
Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes a part of the present invention, and illustrative examples of the present invention and explanation thereof are used to explain the present invention, does not constitute improper qualification of the present invention.In the accompanying drawings:
Fig. 1 is the form sketch map of detection messages preferred embodiment of the present invention;
Fig. 2 is the flow chart of ethernet link detection method preferred embodiment of the present invention;
Fig. 3 is an ethernet link checkout gear preferred embodiment theory diagram of the present invention.
Embodiment
In order to make technical problem to be solved by this invention, technical scheme and beneficial effect clearer, clear,, the present invention is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the present invention, and be not used in qualification the present invention.
As shown in Figure 1, be the form sketch map of detection messages preferred embodiment of the present invention, present embodiment specifically comprises following field:
DA, its value is clean culture MAC for the MAC Address of destination node (detecting the terminal note of link), the intermediate node on the detection link is transmitted to destination node according to the value of this field with detection messages;
SA, its value is clean culture MAC for the MAC Address of source node (initiating the node of link detecting); When detecting the node answer detection messages on the link, use the value of this field to be purpose MAC, will reply message and send to source node;
VLAN Tag, its value is for the vlan information in the Ethernet message, in order to distinguish different VLAN;
Ether Type, its value is the Ethernet type of message, uses the ethernet type 0x8902 of CFM agreement;
MDL, MD Level, identical with the definition in the CFM agreement, value is 0-7;
VER, version number, identical with the definition in the CFM agreement;
OpCode, custom field, whether be used to discern detection messages is the message of current handling process; Can be defined as a value that does not have use, show it is a kind of new CFM message;
Flags, its value is 0;
FirstTLVoffset, identical with the definition in the CFM agreement, among the present invention, its value is 6;
Transaction ID shows that current message is which message of link detecting;
Ttl, its value is time-out time; Intermediate node subtracts 1 with the value of this field when receiving detection messages;
Num, its value for detection messages send after through the node number; Show the MAC information that has write down several intermediate nodes in the detection messages.Initial value is 0, when intermediate node adds local mac address in detection messages, this value is added 1;
MAC, its value for detection messages send after through the MAC Address of node; After intermediate node is received detection messages, oneself MAC Address is added to after the existing information of this field;
EndTLV, identical with the definition in the CFM agreement, show ENMES.
As shown in Figure 2, be the flow chart of ethernet link detection method preferred embodiment of the present invention, present embodiment specifically may further comprise the steps:
Step S01: source node sends to detection messages the next-hop node that detects on the link;
Step S02: the node of receiving detection messages judges whether the value of the OpCode field of above-mentioned detection messages is the detection messages ident value of presetting, if, execution in step S04 then; Otherwise, otherwise, execution in step S03;
Step S03: according to the value of above-mentioned OpCode field, above-mentioned detection messages is transmitted to the corresponding processing flow process, the processing of current detection message finishes, and changes step S02 over to and carries out;
Step S04: whether the value of judging the ttl field of above-mentioned detection messages is 1, if, execution in step S05 then; Otherwise, execution in step S06;
Step S05: the value of above-mentioned ttl field is subtracted 1, execution in step S09;
Step S06: judge whether this node is destination node, if, execution in step S09 then; Otherwise, execution in step S07;
This step judges through judging that local mac address is whether identical with the value of the da field of above-mentioned detection messages whether this node is destination node.
Step S07: judge this node whether with above-mentioned source node in same MA (Maintenance Association safeguards collection), if then this node is a destination node, execution in step S09; Otherwise this node is not a destination node, execution in step S08;
Step S08: local mac address is filled in the MAC field of above-mentioned detection messages; The value of the num field in the above-mentioned detection messages is added 1; The value of ttl field is subtracted 1, above-mentioned detection messages is sent to the next-hop node that detects link, change step S02 over to and carry out;
Step S09: generate and reply message and return to above-mentioned source node;
This step replaces to the value of sa field through the value with the da field of detection messages; The value of above-mentioned sa field is replaced to local MAC Address; The value of the OpCode field of above-mentioned detection messages is replaced to the discre value of preset answer message; The value of the num field of above-mentioned detection messages is added 1, obtain replying message.
Step S10: source node shows the link detecting result according to the answer message of receiving to the user.
As shown in Figure 3, be ethernet link checkout gear preferred embodiment theory diagram of the present invention, present embodiment comprises packet sending and receiving module 10, judge module 20 and display module 30,
Packet sending and receiving module 10 is used to receive and dispatch detection messages and replys message; And when receiving that detection messages and judge module 20 are judged this node and be destination node, the value of the da field of detection messages is replaced to the value of sa field, the value of above-mentioned sa field is replaced to local MAC Address; The value of the OpCode field of above-mentioned detection messages is replaced to the discre value of preset answer message; The value of the num field of above-mentioned detection messages is added 1, generate and reply message and also send to source node; And when judge module 20 is judged this node and is not destination node; Local mac address is filled in the MAC field of above-mentioned detection messages; And the value of the num field in the above-mentioned detection messages added 1, and the value of ttl field is subtracted 1, above-mentioned detection messages is sent to the next-hop node that detects link;
Above-mentioned explanation illustrates and has described the preferred embodiments of the present invention; But as previously mentioned; Be to be understood that the present invention is not limited to the form that this paper discloses, should do not regard eliminating as, and can be used for various other combinations, modification and environment other embodiment; And can in invention contemplated scope described herein, change through the technology or the knowledge of above-mentioned instruction or association area.And change that those skilled in the art carried out and variation do not break away from the spirit and scope of the present invention, then all should be in the protection range of accompanying claims of the present invention.
Claims (10)
1. an ethernet link detection method is characterized in that, said method is:
Source node sends detection messages;
Receive the node of said detection messages judges whether this node is destination node, if, then generate and reply message and return to said source node, otherwise, said detection messages is sent to the next-hop node that detects link;
Said source node shows the link detecting result according to the answer message of receiving to the user.
2. method according to claim 1 is characterized in that, said detection messages comprises following field:
DA, its value is the MAC Address of destination node;
SA, its value is the medium access control MAC Address of source node;
OpCode, custom field, whether be used to discern detection messages is the message of current handling process;
Ttl, its value is time-out time;
Num, its value for detection messages send after through the node number;
MAC, its value for detection messages send after through the MAC Address of node.
3. method according to claim 2 is characterized in that, the said node of receiving detection messages is also carried out following steps before judging whether this node is destination node:
Whether the value of judging the ttl field of said detection messages is 1, if then the value with said ttl field subtracts 1, carries out said generation and replys message and return to the source node step; Otherwise, carry out and saidly judge whether this node is the destination node step.
4. method according to claim 3 is characterized in that, the said node of receiving detection messages is also carried out following steps before whether the value of the ttl field of judging detection messages is 1:
Whether the value of judging the OpCode field of said detection messages is the detection messages ident value of presetting, if then carry out and saidly judge whether the value of the ttl field of detection messages is 1 step; Otherwise,, said detection messages is transmitted to the corresponding processing flow process according to the value of said OpCode field.
5. method according to claim 4 is characterized in that, the said node of detection messages of receiving judges in the following manner whether this node is destination node:
The value with the da field of said detection messages is identical to judge local mac address, if then this node is destination node.
6. method according to claim 5 is characterized in that, the said node of receiving detection messages is also carried out following steps in the value of the da field of judging local mac address and detection messages not simultaneously:
Judge this node whether with said source node in same maintenance collection MA, if then this node is a destination node, otherwise, carry out the said next-hop node step that detects link that detection messages is sent to.
7. according to each described method of claim 3-6, it is characterized in that the said node of receiving detection messages is also carried out following steps before said detection messages being sent to the next-hop node that detects link:
Local mac address is filled in the MAC field of said detection messages;
The value of the num field in the said detection messages is added 1, the value of ttl field is subtracted 1.
8. method according to claim 1 is characterized in that, said generation is replied the message step and is specially:
The value of the da field of detection messages is replaced to the value of sa field;
The value of said sa field is replaced to local MAC Address;
The value of the OpCode field of said detection messages is replaced to the discre value of preset answer message;
The value of the num field of said detection messages is added 1, obtain replying message.
9. an ethernet link checkout gear is characterized in that, said device comprises packet sending and receiving module, judge module and display module,
The packet sending and receiving module is used to receive and dispatch detection messages and replys message; And when receiving that detection messages and said judge module are judged this node and be destination node, generate and reply message and also send to source node; And when said judge module is judged this node and is not destination node, said detection messages is sent to the next-hop node that detects link;
Judge module is used for the detection messages received according to said detection messages transceiver module, judges whether this node is destination node;
Display module is used for the answer message received according to said detection messages transceiver module, shows the link detecting result to the user.
10. device according to claim 9 is characterized in that,
Said packet sending and receiving module; Be used for before the detection messages of receiving being sent to the next-hop node that detects link; Local mac address is filled in the MAC field of said detection messages, and the value of the num field in the said detection messages is added 1, the value of ttl field is subtracted 1; And when this node is destination node, the value of the da field of detection messages is replaced to the value of sa field; The value of said sa field is replaced to local MAC Address; The value of the OpCode field of said detection messages is replaced to the discre value of preset answer message; The value of the num field of said detection messages is added 1;
Said judge module is used to judge whether the value of the OpCode field of said detection messages is the detection messages ident value of presetting; Whether the value of judging the ttl field of said detection messages is 1; The value with the da field of said detection messages is identical to judge local mac address; And judge this node whether with said source node in same MA.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103787176A CN102404171A (en) | 2011-11-24 | 2011-11-24 | Method and device for detecting Ethernet links |
| PCT/CN2012/076852 WO2013075476A1 (en) | 2011-11-24 | 2012-06-13 | Ethernet link detection method and device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011103787176A CN102404171A (en) | 2011-11-24 | 2011-11-24 | Method and device for detecting Ethernet links |
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| CN103051542A (en) * | 2012-12-11 | 2013-04-17 | 武汉烽火网络有限责任公司 | Method for realizing connectivity detection based on data link layer Ethernet MAC (media access control) address |
| WO2013075476A1 (en) * | 2011-11-24 | 2013-05-30 | 中兴通讯股份有限公司 | Ethernet link detection method and device |
| WO2018121589A1 (en) * | 2016-12-30 | 2018-07-05 | 中兴通讯股份有限公司 | Data link detection method, apparatus and system |
| CN110830302A (en) * | 2019-11-13 | 2020-02-21 | 苏州盛科科技有限公司 | Method and device for processing SPN OAM (shortest Path bridging operation and maintenance) in one-layer cross node in Flexe network |
| CN112688826A (en) * | 2019-10-18 | 2021-04-20 | 中车株洲电力机车研究所有限公司 | Link diagnosis method, terminal device, link diagnosis system, and storage medium |
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| WO2013075476A1 (en) | 2013-05-30 |
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Application publication date: 20120404 |