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How Secure are Secure Interdomain Routing
Protocols?
B96209044 大氣四 鍾岳霖B97703099 財金三 婁瀚升
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Outline• Introduction• Model and Methodology• Fooling BGP Security Protocols• Smart Attraction Attack• Smart Interception Attack• Smart Attack Are Not Optimal• Finding Optimal Attack is Hard• Implementation Issues• Conclusion
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Introduction
• BGP• Quantifying– Worst Case Comparison– Traffic Flow: Routing, Business, AS-path
• Thinking like a Manipulator• Finding and Recommendations
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Model and Methodology• Modeling Interdomain Routing– AS Graph– Establishing Path– Business Relationship: C > P2P > P
• Modeling Routing Policies– Ranking: LP, SP, TB– Local Preference: GR3 , C > P2P > P – Export Policy: GR2,at least 1 Customer
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Model and Methodology• Threat Model– 1 Manipulator– Normal ASes, Normal Path– Attration and Interception– Fraction Attracted
• Attack Strategy:– Unavailable or Non-existent Path– Available but not Normal– Export Policies
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• Experiment on Empirical AS Graph– Average Case Analysis– Random Chosen Pairs– Multiple Dataset
Model and Methodology
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Fooling BGP Security Protocols
• BGP: No validation → False Path
• Origin Authentication: Prefix Owner → Clain to be the closest
• soBGP:OrAuth, Path Existence → Exist, Unavail.
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Fooling BGP Security Protocols
• S-BGP: Path Verification: abc if bc sent to a → Shorter Path
• Data Plane Verification → Also Forward
• Defensive Filter : No Stub
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Smart Attraction Attack• Shortest-Path Export All• Underestimation• Defensive Filtering : Crucial• Different Strategy to Different Protocols
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Smart Attraction Attack• SBGP: Hard to find Shorter, Not Opt.• Export Policy Matters More• Different Sized Manipulator : Tier 2• Different Sized Victim : Tier 1 vs Tier2
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• A stub that creates a blackholeSmart Interception Attack
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Smart Interception Attack• Stub Make Blackhole : Failure
• Blackhole or Not
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Smart Interception Attack• 2 Strategies:– Shortest Available Path Export All– Hybrid Interception Attack Strategy
• Evaluation
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Smart Attack are Not Optimal• Longer Path might be better• Exporting less might be better• Gaming Loop Detection
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Exporting less might be better
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Gaming Loop Detection
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But....• Finding Optimal Attack : NP-Hard• Realistic ?• Implementation Issues– OrAuth with RPKI/ROA– Defendive Filtering in Practice– Trust Model
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Conclusion• secure routing protocols (e.g., soBGP
and S-BGP) should be deployed in combination with mechanisms that police export policies (e.g., defensive filtering)
• defensive filtering to eliminate attacks by stub ASes, and secure routing protocols to blunt attacks launched by larger ASes
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Q&A
