Katzenpost
A post-quantum mix network providing strong metadata privacy against global passive adversaries.
What it is
Katzenpost is a free and open-source mix network. It hides who is talking to whom from network-level observers, including adversaries that record traffic today for later decryption on a quantum computer. The design is described in Echomix: a Strong Anonymity System with Messaging.
Beyond messaging, Katzenpost is a substrate for decentralised applications that tolerate ephemeral storage and modest latency: group chat, voting, ephemeral collaborative state, and anonymous integration with existing systems.
Status
- katzenqt — Qt group chat client; buildable from source today, pre-built packages forthcoming.
- kpclientd — client daemon; buildable from source, packages forthcoming.
- Namenlos — a public Katzenpost mix network anyone may use; coming.
- Pigeonhole — anonymous storage protocol; implemented, with thin clients in Go, Rust, and Python.
Threat model
The published Threat Model document is an evolving work in progress and does not yet incorporate the new designs introduced in the paper. To understand the present state of the design, the Echomix paper and the threat model document must be read together.
Where to go
- Documentation — start here. Entry points for users, operators, application developers, core developers, and academics.
- Blog — design notes and protocol explainers.
- Source — the Katzenpost monorepo, the
hpqcpost-quantum cryptography library, thin clients,katzenqt, and this website. - Team · Funders · Presentations.