A survey of DoS attack and defense mechanisms

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A survey of DoS attack and defense mechanisms

• Wei-Min Yao (wmyao_at_cs.purdue.edu)

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Outline

• Introduction
• DoS attack taxonomy
• DoS attack mechanisms
• DoS defense mechanisms
• Summary

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Introduction to denial-of-service attack

• Goal of a DoS attack
• Deny a certain service to legitimate users, such
  as web service or computer system.
• Trends of DoS1
• Distributed Denial of Service attacks (DDoS) is
  the most significant ISP security threat.
• Flooding DoS attacks are the most popular DoS
  attacks
• SYN Floods
• UDP Floods

1 ARBOR Network," Worldwide Infrastructure
Security Report, Sep 2006
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DoS attack taxonomy
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Flooding DoS attacks
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DoS attack mechanisms (1/2)
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DoS attack mechanisms (2/3)

• DNS amplification attack

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DoS attack mechanisms (3/3)

• Low-rate TCP based attack

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DoS Defense Mechanisms
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Defense mechanisms in DoS deployment phase
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Defense mechanisms in DoS attack phase
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Summary

• Trends of DoS attacks
• DoS attacks are increasingly prevalent
• Most attacks are DDoS and flooding attacks
• DoS attack mechanisms
• DoS defense mechanisms
• Defending DoS attack is a challenging problem
• A comprehensive set of defenses has to be
  utilized to defend DoS attacks