CN105007271B - A kind of recognition methods and system of ddos attack Botnet - Google Patents

A kind of recognition methods and system of ddos attack Botnet Download PDF

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CN105007271B
CN105007271B CN201510424040.3A CN201510424040A CN105007271B CN 105007271 B CN105007271 B CN 105007271B CN 201510424040 A CN201510424040 A CN 201510424040A CN 105007271 B CN105007271 B CN 105007271B
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botnet
domain
sbs
attack
measurement
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CN105007271A (en
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肖军
云晓春
张永铮
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Institute of Information Engineering of CAS
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/14—Network architectures or network communication protocols for network security for detecting or protecting against malicious traffic
    • H04L63/1408—Network architectures or network communication protocols for network security for detecting or protecting against malicious traffic by monitoring network traffic
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/14—Network architectures or network communication protocols for network security for detecting or protecting against malicious traffic
    • H04L63/1441—Countermeasures against malicious traffic
    • H04L63/1458—Denial of Service

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Hardware Design (AREA)
  • Computing Systems (AREA)
  • General Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Information Transfer Between Computers (AREA)
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Abstract

The invention discloses the recognition methods and system of a kind of ddos attack Botnet.By measuring each link available bandwidth, the attack traffic that each domain issues is inferred, and then identify the Botnet for starting ddos attack.The present invention is suitable for various agreements independent of specific ddos attack type, and without modifying to conventional network equipment.

Description

A kind of recognition methods and system of ddos attack Botnet
Technical field
The invention belongs to computer network security technology fields, are related to network attack and trace to the source, and in particular to a kind of DDoS is attacked Hit the recognition methods and system of Botnet.
Background technique
Botnet be also be exactly Botnet described in us, refer to using one or more communication means, will largely lead Machine infects bot (bot program), to be formed by the net of one or one-to-many control between controller and infected host Network.The attacker of Botnet is controlled usually using the botnet that it possesses with DDoS (Distribution Denial OfService, distributed denial of service) attack, bank card password is stolen, spam is sent, sensitive information is stolen etc. attacks Mode is made profit.
Ddos attack refers to joins together to occupy as Attack Platform using reasonable service request by multiple computers A large amount of Service Sources of one or more destination servers, so that legitimate user be made to be unable to get the service response of the server.
There is currently the tracing technologies of some ddos attacks, mainly pass through data packet marking of the convection current through router, from And it can be inferred that attack path (link and router that Attacking Packets stream passes through) and the attack source (side of attack package outflow Boundary's router), there are no to the technology for starting the Botnet of ddos attack to be identified.
Summary of the invention
The present invention provides the recognition methods and system of a kind of ddos attack Botnet.Band can be used by measuring each link Width infers the attack traffic that each domain issues, and then identifies the Botnet for starting ddos attack.
To achieve the goals above, the invention adopts the following technical scheme:
A kind of recognition methods of ddos attack Botnet, comprising the following steps:
(1) after detecting ddos attack, the available bandwidth of the data link in each domain is measured respectively, until it is available to meet link Bandwidth measurement accuracy；
(2) according to above-mentioned measurement result, available bandwidth when in conjunction with without attack obtains the attack traffic of corresponding domain sending；
(3) DDoS Botnet is identified in conjunction with the distributed intelligence of zombie host according to obtained attack traffic.
Further, ddos attack is detected using the DDoS detection technique based on entropy.
Further, available bandwidth is measured based on probe messages Rate Models (probe rate model, PRM).
Further, above-mentioned " meeting link available bandwidth measurement precision " refers to the difference of adjacent measurement result twice (i.e. The difference of the two is divided by the minimum value in the two) less than one given threshold.Specifically, it is assumed that previous measurement obtained can It is A1 with bandwidth, the available bandwidth that next one-shot measurement obtains is A2, then | A1-A2 |/min (A1, A2)≤given threshold The required precision for meeting measurement is believed that when THD.This given threshold depend on specific required precision, such as 5% or 3%.
The distributed intelligence of above-mentioned zombie host is primarily referred to as distribution of the bot program (bot) of each Botnet in each domain Ratio.Such as assume there be M domain that (this is according to the topological structure of real network come fixed in how many a domains, can by taking telecommunications as an example To regard the telecommunications of each province as a domain), bot quantity of the Botnet in each domain is N1,N2,...,NM, then in i-th of domain Interior bot distribution ratio is Ni/(N1+N2+…+NM)。
Further, DDoS Botnet is identified according to following methods:
(1) domain is chosen to (di, dj), it is desirable that i, j meetIf there is such domain pair, enter step (2), it otherwise enters step (5), UST indicates the domain compared to set, di, djI-th of domain and j-th of domain are respectively indicated, bi, bjRespectively indicate i-th of Botnet and j-th of Botnet.
(2) if | SBS |=1 or | UST |=M (M-1)/2 enters step (5), otherwise enters step (3), SBS table Show remaining suspicious Botnet set, SBS=BS={ b1,b2,...,bN, BS represents the set for containing N number of Botnet, M The total number of representative domain.
(3) the element b in SBS is chosenn, it is desirable that bnStep (4) are not lived through, if there is such element bn, into step Suddenly (4), otherwise UST=UST+ { (bi, bj), switch to step (1).
(4) if bnMeetAnd vi<vj, then SBS=SBS- { bn, it is transferred to step (2), bnIndicate SBS Any one element,N-th of Botnet is respectively indicated in the zombie host ratio in i-th and j-th domain, Φ table Show recognition threshold, vi, vjRespectively indicate the corresponding attack traffic size in i-th of domain and j-th of domain, 1≤i≤M, 1≤j≤M.
(5) if | SBS | remaining element is exactly the Botnet of offensive attack in=1, SBS, otherwise from SBS with Machine selects Botnet of the element as offensive attack.
A kind of identifying system of ddos attack Botnet, comprising:
Identifier, for identification ddos attack；Link available bandwidth measurement is initiated to instruct to measuring appliance；And according to measurement The Botnet of ddos attack is started in the return information of device, identification；
Measuring appliance, the available bandwidth measurement for receiving identifier instruct；Available bandwidth measurement is initiated to instruct to corresponding domain Measurement point；Receive the measurement data packet that measurement point is sent, measures available bandwidth；Return measurement result is to knowledge after measurement Other device；
Measurement point, the measurement instruction for being sent according to measuring appliance send measurement data packet to corresponding measuring appliance, until Meet measurement accuracy requirement；
Wherein, identifier is deployed on backbone router；Measuring appliance is deployed on the backbone router in one domain of link；It surveys Amount point is deployed on the border router in a domain.
Beneficial effects of the present invention are as follows:
The present invention can effectively identify the Botnet for starting ddos attack, and the present invention is attacked independent of specific DDoS Type is hit, is suitable for various agreements, and without modifying to conventional network equipment.
Detailed description of the invention
Fig. 1 is the system deployment schematic diagram for the Botnet that ddos attack is started in present invention identification, in which: I: identifier (identifier), R: router (router), M: measuring appliance (measurer), A: measurement point (agent), B: bot program (bot), C: client (client).
Fig. 2 is the method flow diagram for the Botnet that ddos attack is started in present invention identification.
Specific embodiment
The invention discloses the method and system that the Botnet of ddos attack is started in a kind of identification.System is introduced separately below System deployment way, system architecture diagram, identification process and core algorithm therein to Botnet.
(1) system introduction and deployment way
System deployment mode is as shown in Figure 1.System includes three parts: identifier (identifier), measuring appliance (measurer) and measurement point (agent).
These three partial functions are described below:
Identifier: identification ddos attack；Link available bandwidth measurement is initiated to instruct to measuring appliance；According to the return of measuring appliance Information infers the Botnet for starting ddos attack.
Measuring appliance: receive the bandwidth measurement instruction of identifier；Available bandwidth measurement is initiated to instruct to the measurement point of corresponding domain； Receive the measurement data packet that measurement point is sent, measures available bandwidth；Return measurement result is to identifier after measurement.
Measurement point: the measurement instruction sent according to measuring appliance sends measurement data packet to corresponding measuring appliance, until meeting Measurement accuracy requirement.
Wherein, identifier is deployed on backbone router；Measuring appliance is deployed on the backbone router in one domain of link；It surveys Amount point is deployed on the border router in a domain.
Domain: domain is usually that perhaps the network segment such as network in a province or a city is considered as a domain to biggish subnet.
(2) identification process
Identification process of the invention is as shown in Fig. 2, mainly comprise the steps that
1) on-line operation identifier (identifier) detects ddos attack；
2) identifier (identifier) transmission available bandwidth measurement, which instructs, gives measuring appliance (measurer)；
3) measuring appliance (measurer) transmission available bandwidth measurement, which instructs, gives corresponding measurement point (agent)；
4) measurement point (agent) sends measurement data packet and gives corresponding measuring appliance (measurer)；
5) judge whether to reach link available bandwidth measurement precision, if not up to, repeatedly step 4)；If reached It arrives, then carries out in next step；
6) measuring appliance (measurer) obtains corresponding domain sending in conjunction with without available bandwidth when attacking according to measurement result Attack traffic；
7) measuring appliance (measurer) returns to attack traffic information result and gives identifier (identifier)；
8) identifier (identifier) is according to returning the result, in conjunction with the zombie host distributed intelligence of Botnet, identification Start the Botnet of ddos attack out.
The present invention uses the DDoS detection technique based on entropy.Specifically refer to IP packet size entropy-based scheme for detection ofDoS/DDoS attacks.
(3) core identification algorithm
Identifier is described below according to zombie host in the distribution situation in each domain and the attack traffic in each domain, identification Start the algorithm of the Botnet of ddos attack.
1) assume to share M domain.Domain collection is combined into DS={ d1,d2,...,dM, the corresponding attack traffic size in i-th of domain is vi(1≤i≤M)；N number of Botnet is shared, Botnet set is BS={ b1,b2,...,bN}；Remaining suspicious corpse net Network set SBS=BS；The domain compared is to set UST={ }.A recognition threshold Φ is set, which is empirical value, is pushed away It recommends and is set as 0.2 or 0.5.Indicate n-th of Botnet in the zombie host ratio in i-th and j-th domain.
2) while | SBS |>1or | DS |<M (M-1)/2:
3) selection domain is to (di,dj), i, j meet
4) any one element b of for SBSn:
5)if bnMeetand vi<vj:
6) SBS:=SBS- { bn}
7)endif
8)endfor
9) UST:=UST+ { (bi,bj)}
10)end while
11)
12) if | SBS |==1then
13) in SBS that remaining element be exactly offensive attack Botnet
14)else
15) Botnet of the element as offensive attack is randomly choosed from SBS.

Claims (9)

1. a kind of recognition methods of ddos attack Botnet, comprising the following steps:
(1) after detecting ddos attack, the available bandwidth of the data link in each domain is measured respectively, until meeting link available bandwidth Measurement accuracy；
(2) according to above-mentioned measurement result, available bandwidth when in conjunction with without attack obtains the attack traffic of corresponding domain sending；
(3) DDoS Botnet, the corpse are identified in conjunction with the distributed intelligence of zombie host according to obtained attack traffic The distributed intelligence of host refers to distribution ratio of the bot program of each Botnet in each domain；Wherein: being known according to following methods Other DDoS Botnet:
1) domain is chosen to (di, dj), it is desirable that i, j meetIf there is such domain pair, enter step 2), it is no It then enters step 5), UST indicates the domain compared to set, di, djRespectively indicate i-th of domain and j-th of domain, bi, bjRespectively Indicate i-th of Botnet and j-th of Botnet；
If 2) | SBS |=1 or | UST | 5)=M (M-1)/2 is entered step, is otherwise entered step 3), SBS indicate it is remaining Suspicious Botnet set, SBS=BS={ b1,b2,...,bN, BS represents the set for containing N number of Botnet, M representative domain Total number；
3) the element b in SBS is chosenn, it is desirable that bnStep 4) is not lived through, if there is such element bn, it enters step 4), Otherwise UST=UST+ { (bi, bj), switch to step 1)；
If 4) bnMeet ri n≥(1+Φ)rj nAnd vi< vj, then SBS=SBS- { bn, it is transferred to step 2), bnIndicate appointing for SBS What element, ri n,rj nN-th of Botnet is respectively indicated in the zombie host ratio in i-th and j-th domain, Φ indicates to know Other threshold value, vi, vjRespectively indicate the corresponding attack traffic size in i-th of domain and j-th of domain, 1≤i≤M, 1≤j≤M；
If 5) | SBS | remaining element is exactly the Botnet of offensive attack in=1, SBS, is otherwise selected at random from SBS Select Botnet of the element as offensive attack.
2. the recognition methods of ddos attack Botnet as described in claim 1, which is characterized in that use the DDoS based on entropy Detection technique detects ddos attack.
3. the recognition methods of ddos attack Botnet as described in claim 1, which is characterized in that be based on probe messages rate Model measurement available bandwidth.
4. the recognition methods of ddos attack Botnet as described in claim 1, which is characterized in that the link that meets can be used Bandwidth measurement accuracy refers to less than one given threshold of difference of adjacent measurement result twice.
5. the recognition methods of ddos attack Botnet as claimed in claim 4, which is characterized in that | A1-A2 |/min (A1, A2)≤THD when, then it is assumed that meet link available bandwidth measurement required precision, wherein A1 indicate it is previous measure obtain can With bandwidth, A2 indicates that the available bandwidth that next one-shot measurement obtains, THD indicate given threshold.
6. the recognition methods of ddos attack Botnet as described in claim 1, which is characterized in that the bot program is each Distribution ratio in domain is Ni/N1+N2+…+NM, i-th of domain of i expression, the number of M representative domain, N1,N2,...,NMIndicate one Bot program quantity of the Botnet in each domain.
7. the recognition methods of ddos attack Botnet as described in claim 1, which is characterized in that identified according to following methods DDoS Botnet:
1) domain is chosen to (di, dj), it is desirable that i, j meetIf there is such domain pair, enter step 2), it is no It then enters step 5), UST indicates the domain compared to set, di, djRespectively indicate i-th of domain and j-th of domain, bi, bjRespectively Indicate i-th of Botnet and j-th of Botnet；
If 2) | SBS |=1 or | UST | 5)=M (M-1)/2 is entered step, is otherwise entered step 3), SBS indicate it is remaining Suspicious Botnet set, SBS=BS={ b1,b2,...,bN, BS represents the set for containing N number of Botnet, M representative domain Total number；
3) the element b in SBS is chosenn, it is desirable that bnStep 4) is not lived through, if there is such element bn, it enters step 4), Otherwise UST=UST+ { (bi, bj), switch to step 1)；
If 4) bnMeet ri n≥(1+Φ)rj nAnd vi< vj, then SBS=SBS- { bn, it is transferred to step 2), bnIndicate appointing for SBS What element, ri n,rj nN-th of Botnet is respectively indicated in the zombie host ratio in i-th and j-th domain, Φ indicates to know Other threshold value, vi, vjRespectively indicate the corresponding attack traffic size in i-th of domain and j-th of domain, 1≤i≤M, 1≤j≤M；
If 5) | SBS | remaining element is exactly the Botnet of offensive attack in=1, SBS, is otherwise selected at random from SBS Select Botnet of the element as offensive attack.
8. a kind of identifying system of ddos attack Botnet, comprising:
Identifier, for identification ddos attack；Link available bandwidth measurement is initiated to instruct to measuring appliance；And according to measuring appliance The Botnet of ddos attack is started in return information, identification, in which: identifies DDoS Botnet according to following methods:
1) domain is chosen to (di, dj), it is desirable that i, j meetIf there is such domain pair, enter step 2), it is no It then enters step 5), UST indicates the domain compared to set, di, djRespectively indicate i-th of domain and j-th of domain, bi, bjRespectively Indicate i-th of Botnet and j-th of Botnet；
If 2) | SBS |=1 or | UST | 5)=M (M-1)/2 is entered step, is otherwise entered step 3), SBS indicate it is remaining Suspicious Botnet set, SBS=BS={ b1,b2,...,bN, BS represents the set for containing N number of Botnet, M representative domain Total number；
3) the element b in SBS is chosenn, it is desirable that bnStep 4) is not lived through, if there is such element bn, it enters step 4), Otherwise UST=UST+ { (bi, bj), switch to step 1)；
If 4) bnMeet ri n≥(1+Φ)rj nAnd vi< vj, then SBS=SBS- { bn, it is transferred to step 2), bnIndicate appointing for SBS What element, ri n,rj nN-th of Botnet is respectively indicated in the zombie host ratio in i-th and j-th domain, Φ indicates to know Other threshold value, vi, vjRespectively indicate the corresponding attack traffic size in i-th of domain and j-th of domain, 1≤i≤M, 1≤j≤M；
If 5) | SBS | remaining element is exactly the Botnet of offensive attack in=1, SBS, is otherwise selected at random from SBS Select Botnet of the element as offensive attack；
Measuring appliance, the available bandwidth measurement for receiving identifier instruct；Available bandwidth measurement is initiated to instruct to the survey of corresponding domain Amount point；Receive the measurement data packet that measurement point is sent, measures available bandwidth；Return measurement result is to identification after measurement Device；
Measurement point, the measurement instruction for being sent according to measuring appliance send measurement data packet to corresponding measuring appliance, until meeting Measurement accuracy requirement.
9. the identifying system of ddos attack Botnet as claimed in claim 8, which is characterized in that the identifier is deployed in On backbone router；The measuring appliance is deployed on the backbone router in one domain of link；The measurement point is deployed in a domain Border router on.
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CN109302427B (en) * 2018-11-30 2020-06-19 西安交通大学 Method for positioning DDoS attack target link of backbone link considering attack precision
CN110225037B (en) * 2019-06-12 2021-11-30 广东工业大学 DDoS attack detection method and device

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