OmniSphinx: Active Mix Networks (Extended Version)

Computer Science > Cryptography and Security [Submitted on 13 Aug 2026] OmniSphinx: Active Mix Networks (Extended Version) Daniel Schadt, Christoph Coijanovic, Shabi Shabani, Thorsten Strufe Mix networks are an important tool to implement anonymous communication, which protects not just the content but also the metadata of messages. Over time, various packet formats for mix networks have been proposed, usually with single, specific goals in mind. These formats are incompatible with each other, requiring separate software and infrastructure to be set up. In this paper, we propose a new format, OmniSphinx, which solves this issue. In OmniSphinx, senders embed code in their packets that determines how they must be processed. The resulting active mix network can emulate any other mix format within a single deployment. Our empirical evaluation shows that emulation in OmniSphinx incurs reasonable overhead compared to native execution for typical mix network use cases: For Sphinx, the most compact format, computation time increases by around 90{\mu}s, while headers increase by 33% in size. Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2608.13008 [cs.CR]   (or arXiv:2608.13008v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2608.13008 Focus to learn more Submission history From: Daniel Schadt [view email] [v1] Thu, 13 Aug 2026 09:26:29 UTC (45 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-08 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)