Hiding Network Metadata: Introduction to Mixnets

Duration: NaN:NaN:NaN

Speaker: Harry Halpin, Max Hampshire

Type: Talk

Expertise: No prior knowledge

Event: Devcon

Date: Nov 2026

In contrast to cryptography that hides the content of a message, network privacy consists of hiding metadata details, like timing and volume information of encrypted messages. Mixnets were invented by David Chaum in which encrypted messages were shuffled like a deck of cards effectively anonymizing the message. While Tor works against weaker adversaries, Tor from its origin explicitly rules out of scope a global passive adversary (such as Palantir or Chainalysis) that could watch every single message on the network. In contrast, mixnets should be able withstand even this powerful adversary . We'll introduce overview different designs and academic research, from Chaumian mixnets used by the original cypherpunks like Mixmaster, continuous-time layered mixnets like Nym to hop-by-hop mixnets like HOPR. We'll explain how to measure anonymity using entropy to compare designs and issues with timing and cover traffic, and end with integration points for Ethereum like RPC nodes and wallets.