Tarzan: A peer-to-peer anonymizing network layer

Michael J. Freedman, Robert Morris

Research output: Contribution to conferencePaperpeer-review

475 Scopus citations


Tarzan is a peer-to-peer anonymous IP network overlay. Because it provides IP service, Tarzan is general-purpose and transparent to applications. Organized as a decentralized peer-to-peer overlay, Tarzan is fault-tolerant, highly scalable, and easy to manage. Tarzan achieves its anonymity with layered encryption and multi-hop routing, much like a Chaumian mix. A message initiator chooses a path of peers pseudo-randomly through a restricted topology in a way that adversaries cannot easily influence. Cover traffic prevents a global observer from using traffic analysis to identify an initiator. Protocols toward unbiased peer-selection offer new directions for distributing trust among untrusted entities. Tarzan provides anonymity to either clients or servers, without requiring that both participate. In both cases, Tarzan uses a network address translator (NAT) to bridge between Tarzan hosts and oblivious Internet hosts. Measurements show that Tarzan imposes minimal overhead over a corresponding non-anonymous overlay route.

Original languageEnglish (US)
Number of pages14
StatePublished - 2002
Externally publishedYes
EventProceedings of the 9th ACM Conference on Computer and Communications Security - Washington, DC, United States
Duration: Nov 18 2002Nov 22 2002


OtherProceedings of the 9th ACM Conference on Computer and Communications Security
Country/TerritoryUnited States
CityWashington, DC

All Science Journal Classification (ASJC) codes

  • Software
  • Computer Networks and Communications


Dive into the research topics of 'Tarzan: A peer-to-peer anonymizing network layer'. Together they form a unique fingerprint.

Cite this