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GCIH · Question #202

Which of the following is an Internet mapping technique that relies on various BGP collectors that collect information such as routing updates and tables and provide this information publicly?

The correct answer is C. AS PATH Inference. AS PATH Inference is the Internet mapping technique that leverages publicly available BGP route collectors - such as RouteViews and RIPE RIS - to gather routing tables and updates for topology analysis.

Reconnaissance, Scanning, and Enumeration

Question

Which of the following is an Internet mapping technique that relies on various BGP collectors that collect information such as routing updates and tables and provide this information publicly?

Options

  • AAS Route Inference
  • BPath MTU discovery (PMTUD)
  • CAS PATH Inference
  • DFirewalking

How the community answered

(44 responses)
  • A
    2% (1)
  • B
    5% (2)
  • C
    91% (40)
  • D
    2% (1)

Why each option

AS PATH Inference is the Internet mapping technique that leverages publicly available BGP route collectors - such as RouteViews and RIPE RIS - to gather routing tables and updates for topology analysis.

AAS Route Inference

AS Route Inference is not a recognized standard Internet mapping technique; it conflates 'AS' terminology with a non-existent methodology.

BPath MTU discovery (PMTUD)

Path MTU Discovery (PMTUD) is a mechanism defined in RFC 1191 for determining the maximum transmission unit along a network path, not an Internet topology mapping technique.

CAS PATH InferenceCorrect

AS PATH Inference relies on BGP route collectors that establish peering sessions with routers worldwide to passively gather full BGP routing tables and incremental update messages. This publicly shared data allows researchers and analysts to infer the autonomous system-level topology of the Internet and reconstruct the paths traffic takes between networks.

DFirewalking

Firewalking uses TTL-expiring packets to probe firewall rulesets and identify allowed ports, and has nothing to do with BGP collectors or Internet-scale mapping.

Concept tested: BGP-based Internet topology mapping via AS PATH inference

Topics

#BGP#AS PATH inference#internet mapping#routing tables

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