CN101330496A - Method and apparatus for detecting Ethernet multicast loop - Google Patents
Method and apparatus for detecting Ethernet multicast loop Download PDFInfo
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- CN101330496A CN101330496A CNA2007100761106A CN200710076110A CN101330496A CN 101330496 A CN101330496 A CN 101330496A CN A2007100761106 A CNA2007100761106 A CN A2007100761106A CN 200710076110 A CN200710076110 A CN 200710076110A CN 101330496 A CN101330496 A CN 101330496A
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Abstract
The invention discloses a method for detecting an ethernet multicast loop, and a device thereof. The method comprises the following steps: a first IGMP inquiry message is sent in an ethernet to be detected; the received IGMP inquiry message is monitored; whether the IGMP inquiry message belongs to the first IGMP inquiry message or not is judged, and if so, a multicast loop exists in the ethernet. The device comprises a sending unit used for sending the first IGMP inquiry message in the ethernet to be detected, a monitoring unit used for monitoring the received IGMP inquiry message and a judging unit used for judging whether the IGMP inquiry message belongs to the first IGMP inquiry message or not and determining that the multicast loop exists in the ethernet when the IGMP inquiry message belongs to the first IGMP inquiry message. Through the implementation of the invention, the circumstance that the multicast loop appears in the network can be automatically detected, therefore, the network administrator can be reminded in time to eliminate network hidden dangers, the broadcasting storm can be avoided, and the excellent network performance can be provided.
Description
Technical field
The present invention relates to network communications technology field, particularly a kind of method and device that detects the Ethernet multicast loop.
Background technology
Along with the fast development of the network communications technology, also increasingly extensive based on the multicast service of Ethernet.Fig. 1 realizes scene graph for the Ethernet multicast service.As shown in Figure 1, main frame H and switch S1, S2, S3 and S4 are in an ethernet segment, when main frame H desire adds a multicast group G1, to send a report (Report) message, switch S1 and S3 will receive described report message, switch S1 is transmitted to switch S2 with described report message then, be transmitted to S4 by switch S2 again, S4 is transmitted to S3 again, S3 is transmitted to multicast router R again, form the forward-path shown in arrow among the figure at last, and on multicast router R, set up corresponding multicast forward table.When multicast traffic stream arrives multicast router R, described multicast router R will be forwarded to switch S1 place with multicast traffic stream along described forward-path according to the multicast forward table of correspondence, send in the network segment of main frame H connection by switch S1 again, received by switch S3 simultaneously.At this moment switch S3 can be forwarded to switch S4 again, so just forms loop, and described multicast packet fails to be convened for lack of a quorum and infinitely transmit along loop, can't eliminate.When the unlimited multicast data traffic of transmitting is increasing on the loop, will take a large amount of network bandwidths, cause network congestion, have a strong impact on network performance, these multicast data traffics will exhaust the bandwidth of whole network (or link) at last, cause network paralysis.The above is exactly the broadcast storm problem that is caused by multicast loop during present Ethernet is used.
For solving the broadcast storm problem, industry method commonly used is to use STP (Spanning-Tree Protocol, Spanning Tree Protocol) technology to eliminate multicast loop at present, avoids the generation of broadcast storm.Yet, when network breaks down or topology network when changing, need to use the STP technology recomputate and generate tree, extend along with the increase of network and calculate the time that generates tree, usually in level second, bigger network even at tens seconds, seconds up to a hundred.The time of network convergence is slow, and this is to carrier network, and the network that key business particularly is provided is unacceptable.Moreover, generate the port that tree needs to block some redundant links, artificially wasted bandwidth.After using the generation tree, the path of any two equipment rooms has only unique one, therefore can't implement traffic engineering.
Summary of the invention
For solving above-mentioned problems of the prior art, the embodiment of the invention provides a kind of method and device that detects the Ethernet multicast loop, automatically the situation of multicast loop occurs in the detection network, thereby avoid the generation of broadcast storm, good reliable network performance is provided.
The method of the detection Ethernet multicast loop that the embodiment of the invention provided may further comprise the steps:
In Ethernet to be measured, send the first Internet Group Management Protocol igmp querying message;
The igmp querying message that monitoring reception arrives;
Judge whether described igmp querying message is the described first igmp querying message,, then determine to have multicast loop in the described Ethernet if judged result is for being.
The device of the detection Ethernet multicast loop that the embodiment of the invention provided comprises:
Transmitting element is used for sending the first Internet Group Management Protocol igmp querying message in Ethernet to be measured;
Monitoring unit is used for the igmp querying message that monitoring reception arrives; And
Judging unit is used to judge whether described igmp querying message is the described first igmp querying message, if judged result is for being, then determines to have multicast loop in the described Ethernet.
From the technical scheme of the above embodiment of the invention as can be seen:
The embodiment of the invention is by sending the igmp querying message and judging whether to receive the mode of the described query message that is sent by this locality in Ethernet, can detect the situation that occurs multicast loop in the network automatically, thereby can in time remind the network manager to eliminate hidden network danger, avoid the generation of broadcast storm, and can prevent impersonation attack, good reliable transmission performance is provided.In addition, the embodiment of the invention does not need that other switching equipment provide any additional function in the detected Ethernet, can not influence the realization of any other switching equipment function yet, is widely used.
Description of drawings
Fig. 1 is that the Ethernet multicast service is realized scene graph.
Fig. 2 is the flow chart that the embodiment of the invention detects the method for Ethernet multicast loop.
Fig. 3 is the module map that the embodiment of the invention detects the device of Ethernet multicast loop.
Embodiment
The invention will be further described below in conjunction with the drawings and specific embodiments, but the present invention is not limited to the following examples.
The embodiment of the invention provides a kind of method that detects the Ethernet multicast loop, mainly be by in Ethernet to be measured, sending Internet Group Management Protocol (IGMP) query message, and whether receive according to transmitting terminal that the described igmp querying message that is sent by this locality is judged and determine whether there is multicast loop in the described Ethernet to be measured.The detection method of the embodiment of the invention can realize on one or more switching equipment of appointment in ethernet segment to be measured, send the igmp querying message by described switching equipment, judge whether to receive by described switching equipment the described igmp querying message that is sent by this locality determines whether there is multicast loop in the ethernet segment to be measured then.Wherein, described igmp querying message is carried in the IP message, can be chosen as general polling message or designated groups query message according to concrete applicable cases.The form of igmp querying message is as shown in table 1:
0 1 2 3
0?1?2?3?4?5?6?7?8?9?0?1?2?3?4?5?6?7?8?9?0?1?2?3?4?5?6?7?8?9?0?1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type |?Max?Resp?Time?| Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group?Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Table 1
In table 1, " Type " is the type of message field, and 0x11 represents the query message type; " Max RespTime " is the maximum response time field; " Checksum " is 16 bit checks and field; " Group Address " is that 32 hytes are broadcast address field.
When the igmp querying message was the designated groups query message, corresponding source IP address was the IP address of message source, promptly sends the IP address of the switching equipment of described igmp querying message; Purpose IP address is the multicast address of designated groups; IP protocol number is 2; Multicast address field in the message also is the multicast address of designated groups.Described designated groups query message will send to all multicast member place ports in the transmitting of designated groups.
When the igmp querying message was the general polling message, corresponding source IP address was the IP address of message source, promptly sends the IP address of the switching equipment of described igmp querying message; Purpose IP address is 224.0.0.1; IP protocol number is 2; Multicast address field in the message is 0.Described general polling message will be broadcast on other all of the ports except that router port.
Do not have the IP address if be used to detect the switching equipment of multicast loop, then carry out disposing an IP address to described switching equipment earlier before multicast loop detects sending the igmp querying message, and this IP address is unique Ethernet scope planted agent to be measured.
See also Fig. 2, the method that the embodiment of the invention detects the Ethernet multicast loop specifically may further comprise the steps:
Step 101: in Ethernet to be measured, send the first igmp querying message.Wherein, the source IP address of the described first igmp querying message correspondence then can be determined according to actual conditions for the IP address of the switching equipment of this message of transmission, purpose IP address.If the described first igmp querying message is the designated groups query message, then Dui Ying purpose IP address is the multicast address of designated groups; If the described first igmp querying message is the general polling message, then Dui Ying purpose IP address is 224.0.0.1.Described switching equipment will be noted the source IP address and the purpose IP address of the described first igmp querying message when sending the described first igmp querying message.
In addition, described switching equipment is when sending the described first igmp querying message, can also start a timer simultaneously, the time-out time of described timer is provided with rule: suppose that the described first igmp querying message needed time of forwarding through all devices in Ethernet to be measured is t, then the time-out time of timer can be set at any one value that is not less than t.In order to realize conveniently, directly get the time-out time of t value usually as timer.
Step 102: the igmp querying message that monitoring reception arrives.Described switching equipment will be monitored the igmp querying message that all of the port receives, and described monitoring step is specially resolves source IP address and the purpose IP address that obtains described igmp querying message.When starting described timer, then described switching equipment will be monitored all igmp querying messages that receive in the described time-out time.
Step 103: judge whether described igmp querying message is the described first igmp querying message,,, then determine not have multicast loop in the described Ethernet if judged result is not if judged result is then determined to have multicast loop in the described Ethernet for being.The detailed process of described judgement is: whether the source IP address of more described igmp querying message is identical with the source IP address of the described first igmp querying message of local record; If the source IP address of the two is identical, determines that then described igmp querying message is exactly the described first igmp querying message that is sent by this locality, and determine to have multicast loop in the described Ethernet; Otherwise, if the source IP address difference of the two is determined that then described igmp querying message is not the described first igmp querying message, and can be determined not exist in the described Ethernet multicast loop.
For preventing the influence of impersonation attack, the described detection method of the embodiment of the invention also provides a kind of more excellent selection scheme in above-mentioned steps 103: whether the source IP address of more described igmp querying message is identical with the source IP address of the described first igmp querying message of local record, and whether the purpose IP address of more described igmp querying message is identical with the purpose IP address of the described first igmp querying message of local record; If the source IP address of the two is all identical with purpose IP address, illustrate that then described igmp querying message is exactly the described first igmp querying message that is sent by this locality, just can determine to have multicast loop in the described Ethernet this moment; Otherwise, if the source IP address of the source IP address of described igmp querying message or purpose IP address and local record or purpose IP address are also incomplete same, that is source IP address difference of the two or purpose IP address difference, illustrate that then described igmp querying message is not the described first igmp querying message, just can determine not exist in the described Ethernet multicast loop this moment.
In embodiments of the present invention, can detect the situation that whether has multicast loop in the network automatically by the mode of the regular transmission first igmp querying message.Because it is that the mode that directly regularly sends the first igmp querying message on the switching equipment of Ethernet appointment to be measured detects the situation that occurs multicast loop in the network automatically that the embodiment of the invention detects the method for Ethernet multicast loop, thereby can in time remind network manager's cancellation loop problem, avoid the generation of broadcast storm, and good reliable network performance can be provided.
See also Fig. 3 again, the embodiment of the invention also provides a kind of device that detects the Ethernet multicast loop, and described device comprises: transmitting element is used for sending the first igmp querying message in Ethernet to be measured; Monitoring unit is used for the igmp querying message that monitoring reception arrives; And judging unit, be used to judge whether described igmp querying message is the described first igmp querying message,, then determine to have multicast loop in the described Ethernet if judged result is for being, if judged result is then determined not have multicast loop in the described Ethernet for not.Wherein, described transmitting element comprises a record subelement, is used to write down the source IP address of the described first igmp querying message, the source IP address and the purpose IP address that perhaps are used to write down the described first igmp querying message.Described monitoring unit comprises the parsing subelement, is used to resolve source IP address and the purpose IP address that obtains described igmp querying message.Described judging unit comprises comparison subelement and definite subelement, whether the source IP address that wherein said relatively subelement is used for more described igmp querying message is identical with the source IP address of the described first igmp querying message of described record subelement record, and perhaps the source IP address of the described first igmp querying message that whether writes down with described record subelement respectively of the source IP address of more described simultaneously igmp querying message and purpose IP address is corresponding identical with purpose IP address; Described definite subelement is used for determining whether there is multicast loop in the described Ethernet according to the described relatively comparative result of subelement.
In addition, the described checkout gear of the embodiment of the invention can comprise further that also one is used to set the timer of time-out time, and described monitoring unit is used for the igmp querying message that monitoring reception arrives in described time-out time.Described timer also can directly be arranged in the described monitoring unit.
The described checkout gear of the embodiment of the invention can be arranged on one or more switching equipment of appointment in the described Ethernet, to realize detecting automatically the function of Ethernet multicast loop, thereby can in time remind network manager's cancellation loop problem, avoid the generation of broadcast storm, and can prevent impersonation attack, good reliable network performance is provided.
More than just preferred implementation of the present invention is described, those skilled in the art is in the scheme scope of the technology of the present invention, and common variation and the replacement carried out all should be included in protection scope of the present invention.
Claims (21)
1, a kind of method that detects the Ethernet multicast loop is characterized in that, may further comprise the steps:
In Ethernet to be measured, send the first Internet Group Management Protocol igmp querying message;
The igmp querying message that monitoring reception arrives;
Judge whether described igmp querying message is the described first igmp querying message,, then determine to have multicast loop in the described Ethernet if judged result is for being.
2, the method for claim 1 is characterized in that, the described first igmp querying message is the general polling message.
3, the method for claim 1 is characterized in that, the described first igmp querying message is the designated groups query message.
4, the method for claim 1 is characterized in that, described method is to realize on the switching equipment of appointment in described Ethernet.
5, method as claimed in claim 4 is characterized in that, described method further comprises: before the described transmission first igmp querying message, be IP address of described switching equipment configuration.
6, the method for claim 1 is characterized in that, described method further comprises: the source IP address and the purpose IP address of writing down the described first igmp querying message.
7, method as claimed in claim 6 is characterized in that, the detailed process of the igmp querying message that described monitoring reception arrives is for resolving source IP address and the purpose IP address that obtains described igmp querying message.
8, method as claimed in claim 7, it is characterized in that, describedly judge that whether described igmp querying message is that the detailed process of the described first igmp querying message is: whether the source IP address of more described igmp querying message is identical with the source IP address of the described first igmp querying message, and whether the purpose IP address of more described igmp querying message is identical with the purpose IP address of the described first igmp querying message, if the source IP address of described igmp querying message and the described first igmp querying message is all identical with purpose IP address, then determine to have multicast loop in the described Ethernet.
9, the method for claim 1 is characterized in that, described method further comprises: the source IP address that writes down the described first igmp querying message.
10, method as claimed in claim 9 is characterized in that, the detailed process of the igmp querying message that described monitoring reception arrives is for resolving the source IP address that obtains described igmp querying message.
11, method as claimed in claim 10, it is characterized in that, describedly judge that whether described igmp querying message is that the detailed process of the described first igmp querying message is: whether the source IP address of more described igmp querying message is identical with the source IP address of the described first igmp querying message, if described igmp querying message is identical with the source IP address of the described first igmp querying message, then determine to have multicast loop in the described Ethernet.
12, the method for claim 1, it is characterized in that, described monitoring reception to the step of igmp querying message be specially and monitor the igmp querying message that receives in the scheduled time, the described scheduled time is not less than the described first igmp querying message needed time of forwarding through all devices in described Ethernet.
13, a kind of device that detects the Ethernet multicast loop is characterized in that, comprising:
Transmitting element is used for sending the first Internet Group Management Protocol igmp querying message in Ethernet to be measured;
Monitoring unit is used for the igmp querying message that monitoring reception arrives; And
Judging unit is used to judge whether described igmp querying message is the described first igmp querying message, if judged result is for being, then determines to have multicast loop in the described Ethernet.
14, device as claimed in claim 13 is characterized in that, described transmitting element comprises a record subelement, the source IP address and the purpose IP address that are used to write down the described first igmp querying message.
15, device as claimed in claim 14 is characterized in that, described monitoring unit comprises the parsing subelement, is used to resolve source IP address and the purpose IP address that obtains described igmp querying message.
16, device as claimed in claim 15, it is characterized in that, described judging unit comprises comparison subelement and definite subelement, whether the source IP address that wherein said relatively subelement is used for more described igmp querying message is identical with the source IP address that is recorded in the local described first igmp querying message, and whether the purpose IP address of more described igmp querying message is identical with the purpose IP address that is recorded in the local described first igmp querying message; Described definite subelement is used for determining whether there is multicast loop in the described Ethernet according to the described relatively comparative result of subelement.
17, device as claimed in claim 13 is characterized in that, described transmitting element comprises a record subelement, is used to write down the source IP address of the described first igmp querying message.
18, device as claimed in claim 17 is characterized in that, described monitoring unit comprises the parsing subelement, is used to resolve the source IP address that obtains described igmp querying message.
19, device as claimed in claim 18, it is characterized in that, described judging unit comprises comparison subelement and definite subelement, and whether the source IP address that wherein said relatively subelement is used for more described igmp querying message is identical with the source IP address that is recorded in the local described first igmp querying message; Described definite subelement is used for determining whether there is multicast loop in the described Ethernet according to the described relatively comparative result of subelement.
20, device as claimed in claim 10 is characterized in that, comprises that also one is used to set the timer of time-out time, and described monitoring unit is used for the igmp querying message that monitoring reception arrives in described time-out time.
21, device as claimed in claim 20 is characterized in that, described timer is arranged in the described monitoring unit.
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Cited By (8)
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| CN102045218A (en) * | 2010-12-07 | 2011-05-04 | 成都市华为赛门铁克科技有限公司 | Loop detection method and firewall device |
| CN102752197A (en) * | 2012-06-25 | 2012-10-24 | 浙江宇视科技有限公司 | Method for simulating IGMP (internet group management protocol) finder and switch |
| CN103581028A (en) * | 2013-11-06 | 2014-02-12 | 盛科网络（苏州）有限公司 | Multicast loop prevention method and device based on spanning tree protocol |
| CN104113442A (en) * | 2013-04-18 | 2014-10-22 | 上海斐讯数据通信技术有限公司 | Ethernet loop detection system and method |
| CN109218192A (en) * | 2018-06-21 | 2019-01-15 | 甘肃万维信息技术有限责任公司 | A kind of data share exchange method based on particle swarm algorithm |
| CN109617837A (en) * | 2018-12-10 | 2019-04-12 | 浪潮(北京)电子信息产业有限公司 | The anti-downright bad implementation method in exchange network port, device, equipment and storage medium |
| CN114448907A (en) * | 2022-04-11 | 2022-05-06 | 希诺麦田技术（深圳）有限公司 | Multicast flooding prevention method, device and equipment |
| CN115941534A (en) * | 2022-12-08 | 2023-04-07 | 贵州电网有限责任公司 | Network storm source tracing method for local area network of power system |
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| US6654371B1 (en) * | 1999-04-15 | 2003-11-25 | Nortel Networks Limited | Method and apparatus for forwarding multicast data by relaying IGMP group membership |
| US6856599B1 (en) * | 2000-09-13 | 2005-02-15 | Harris Corporation | System and method of reducing retransmission of messages in a TCP/IP environment |
| US7349680B2 (en) * | 2002-04-29 | 2008-03-25 | Broadcom Corporation | Method and system for using PSK sync word for fine tuning frequency adjustment |
| US20060285499A1 (en) * | 2005-06-17 | 2006-12-21 | Broadcom Corporation | Loop detection for a network device |
| CN100433665C (en) * | 2006-11-07 | 2008-11-12 | 华为技术有限公司 | Internet group management protocol listening method and switch |
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| CN102045218A (en) * | 2010-12-07 | 2011-05-04 | 成都市华为赛门铁克科技有限公司 | Loop detection method and firewall device |
| CN102045218B (en) * | 2010-12-07 | 2012-11-07 | 成都市华为赛门铁克科技有限公司 | Loop detection method and firewall device |
| CN102752197A (en) * | 2012-06-25 | 2012-10-24 | 浙江宇视科技有限公司 | Method for simulating IGMP (internet group management protocol) finder and switch |
| CN102752197B (en) * | 2012-06-25 | 2018-12-07 | 浙江宇视科技有限公司 | A kind of method and interchanger for simulating igmp querying device |
| CN104113442A (en) * | 2013-04-18 | 2014-10-22 | 上海斐讯数据通信技术有限公司 | Ethernet loop detection system and method |
| CN103581028A (en) * | 2013-11-06 | 2014-02-12 | 盛科网络（苏州）有限公司 | Multicast loop prevention method and device based on spanning tree protocol |
| CN109218192A (en) * | 2018-06-21 | 2019-01-15 | 甘肃万维信息技术有限责任公司 | A kind of data share exchange method based on particle swarm algorithm |
| CN109218192B (en) * | 2018-06-21 | 2021-04-20 | 中电万维信息技术有限责任公司 | Data sharing and exchanging method based on particle swarm algorithm |
| CN109617837A (en) * | 2018-12-10 | 2019-04-12 | 浪潮(北京)电子信息产业有限公司 | The anti-downright bad implementation method in exchange network port, device, equipment and storage medium |
| CN114448907A (en) * | 2022-04-11 | 2022-05-06 | 希诺麦田技术（深圳）有限公司 | Multicast flooding prevention method, device and equipment |
| CN114448907B (en) * | 2022-04-11 | 2022-07-22 | 希诺麦田技术（深圳）有限公司 | Multicast flooding prevention method, device and equipment |
| CN115941534A (en) * | 2022-12-08 | 2023-04-07 | 贵州电网有限责任公司 | Network storm source tracing method for local area network of power system |
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