XRD: Scalable messaging system with cryptographic privacy
Name
1901.04368.pdf
Description
Accepted version
Size
499.5 KB
Format
Adobe PDF
Checksum (MD5)
5cf4b5efbe6b0c9e51dce9a0cdbf8df6
Author(s)
Kwon, Albert Hyukjae
Lu, David
Devadas, Srinivas
Date Issued
February 2020
Journal
Proceedings of the 17th USENIX Symposium on Networked Systems Design and Implementation, NSDI 2020
Citation
Kwon, Albert “XRD: Scalable messaging system with cryptographic privacy.” Paper in the Proceedings of NSDI USENIX Symposium on Networked Systems Design and Implementation, 17th USENIX Symposium on Networked Systems Design and Implementation, NSDI 2020, Santa Clara CA, Feb 25-27 2020, USENIX, ACM SIGCOMM, and ACM SIGOPS © 2020 The Author(s)
Version
Author's final manuscript
Abstract
Even as end-to-end encrypted communication becomes more popular, private messaging remains a challenging problem due to metadata leakages, such as who is communicating with whom. Most existing systems that hide communication metadata either (1) do not scale easily, (2) incur significant overheads, or (3) provide weaker guarantees than cryptographic privacy, such as differential privacy or heuristic privacy. This paper presents XRD (short for Crossroads), a metadata private messaging system that provides cryptographic privacy, while scaling easily to support more users by adding more servers. At a high level, XRD uses multiple mix networks in parallel with several techniques, including a novel technique we call aggregate hybrid shuffle. As a result, XRD can support 2 million users with 228 seconds of latency with 100 servers. This is 13.3× and 4× faster than Atom and Pung, respectively, which are prior scalable messaging systems with cryptographic privacy.
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://www.usenix.org/conference/nsdi20
