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Title: Easy-to-Implement Two-Server based Anonymous Communication with Simulation Security
Anonymous communication, that is secure end-to-end and unlinkable, plays a critical role in protecting user privacy by preventing service providers from using message metadata to discover communication links between any two users. Techniques, such as Mix-net, DC-net, time delay, cover traffic, Secure Multiparty Computation (SMC) and Private Information Retrieval, can be used to achieve anonymous communication. SMC-based approach generally offers stronger simulation based security guarantee. In this paper, we propose a simple and novel SMC approach to establishing anonymous communication, easily implementable with two non-colluding servers which have only communication and storage related capabilities. Our approach offers stronger security guarantee against malicious adversaries without incurring a great deal of extra computation. To show its practicality, we implemented our solutions using Chameleon Cloud to simulate the interactions among a million users, and extensive simulations were conducted to show message latency with various group sizes. Our approach is efficient for smaller group sizes and sub-group communication while preserving message integrity. Also, it does not have the message collision problem.  more » « less
Award ID(s):
1946619
NSF-PAR ID:
10435842
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
2022 ACM on Asia Conference on Computer and Communications Security
Page Range / eLocation ID:
831 to 842
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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