We introduce the concept of membership-concealing overlay networks (MCONs), which hide the real-world identities of participants. We argue that while membership concealment is orthogonal to anonymity and censorship resistance, pseudonymous communication and censorship resistance become much easier if done over a membership-concealing network. We formalize the concept of membership concealment, discuss a number of attacks against existing systems and present real-world attack results. We then propose three proof-of-concept MCON designs that resist those attacks: one that is more efficient, another that is more robust to membership churn, and a third that balances efficiency and robustness. We show theoretical and simulation results demonstrating the feasibility and performance of our schemes.
@inproceedings{mcon-ccs2009,
title = {Membership-Concealing Overlay Networks},
author = {Vasserman, Eugene and Jansen, Rob and Tyra, James and Hopper, Nicholas and Kim, Yongdae},
booktitle = {Conference on Computer and Communications Security},
year = {2009},
doi = {10.1145/1653662.1653709},
}