Anatomy of a Large European IXP

B. Ager, N. Chatzis, N. Sarrar TU Berlin/Telekom Innovation Laboratories

To appear at ACM SIGCOMM, Helsinki, Finland, August 2012

Anja Feldmann TU Berlin/Telekom Innovation Laboratories

W. Willinger AT&T Labs Research

S. Uhlig Queen Mary

University of London

The changing Internet

❒ What is your mental model of the Internet? ❍ What Internet does it capture? ❍  Today’s Internet?

❒  Some thoughts about local traffic and connectivity: ❍  IXPs can be as large as the top ISPs in the world ❍  Lots of data-centers/hosting locations around the

world

Internet: Accepted mental model

Internet – Network of networks

Accepted mental model of the Internet ❒ 35,000+ networks ❒ Hierarchical structure

❍  Tier-1 (10-20): ATT, L3, Sprint, DTAG, … ❍ Regional ISPs (15%): BT, Telefonica, … ❍  Stubs (85%): small ISPs, universities, enterprise

networks

❒ Known AS connectivity ❍ Customer-provider: 90,000+ ❍  Peer-peer: 35-40,000

Most recent mental model – a 2011

à  Flattening of the AS topology

Google, Akamai,

RapidShare, …

Source: Arbor Networks 2009

Question – What about IXPs

à  Flattening of the AS topology à  What about IXPs impact

Google, Akamai,

RapidShare, … IXP

Source: Arbor Networks 2009

Outline

❒ Motivation ❒  IXP ecosystem ❒ Diversity ❒  Visibility ❒  Conclusion

IXP – architecture/business model

à  Offers connectivity à  Enables peering

Internet exchange point (IXP)

à  Traffic Volume: Same as Tier-1 ISPs à  Clear daily patterns

Traffic mix

IXP members

Outline

❒ Motivation ❒  IXP ecosystem ❒ Diversity ❒  Visibility ❒  Conclusion

Members business types

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Lines at ratios20:1, 3:1, 1:1, 1:3, and 1:20

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Outline

❒ Motivation ❒  IXP ecosystem ❒ Diversity ❒  Visibility ❒  Conclusion

Public view of P-P peerings à  Peering links at IXP: > 50K à  ~40K peerings are publicly known so far

Visibility of IXP peerings

Potential visibility of IXP traffic

Network map 2012+ Google, Akamai,

RapidShare, …

Source: Arbor Networks 2009

à  Even more flattening of the AS topology à  IXPs central component à  Lots of local peering

IXP

Outline

❒ Motivation ❒  IXP ecosystem ❒  Visibility ❒ Diversity ❒  Conclusion

Summary

❒  Revisiting mental model of the Internet ❒ Much more P-P peerings out there:

❍ A single IXP with 300+ members more than doubles known P-P peerings

❒  Poor visibility of IXP peerings and traffic ❒  IXP has a rich ecosystem:

❍ Members ❍  Traffic ❍ Geography