STATUS: Not actively maintained; bibliograpy now updated in Zotero group https://www.zotero.org/groups/2306124/vacp2p/items for https://vac.dev/

Awesome Secure Messaging

A curated collection of links for secure messaging. Part of the "Awesome X" series.

The list is periodically updated with new links. Click "Watch" in the right top corner to follow.

Your contributions are welcomed.

Fundamentals

SoK: Secure Messaging - evaluation of current secure messaging solutions based on security, usability and adoption
Viewing Privacy as a Security Property - presentation by George Danezis that tells the story of privacy as security, informational self-determination

Double Ratchet - two-party protocol to exchange encrypted messages based on shared key
Bramble Transport Protocol - transport layer security protocol for delay-tolerant networks, provides secure channel between two endpoints
Bramble Synchronisation Protocol - data synchronisation protocol for delay-tolerant networks
TreeKEM - Asynchronous Decentralized Key Management for Large Dynamic Groups - efficient way of establishing shared key for large groups with asynchronous group modification perations; proposal for Messaging Layer Security protocol (MLS); similar to Asynchronous Ratcheting Trees (ART) and an evolution thereof
On Ends-to-Ends Encryption - Asynchronous Group Messaging with Strong Security Guarantees using Asynchronous Ratcheting Trees
Messaging Layer Security Architecture - IETF draft of security layer for group messaging applications with a large number of participants

X3DH - two-party asynchronous key agreement protocol
Bramble QR Code Protocol - in-person key agreement protocol to establish a shared secret

The Differences Between Onion Routing and Mix Networks - brief comparison
Anonymity Trilemma: Strong Anonymity, Low Bandwidth Overhead, Low Latency—Choose Two - on fundamental tradeoff for anonymous communication protocols
Selected Papers in Anonymity - meta-list of selected papers in anonymity since 1977
Sphinx: A Compact and Provably Secure Mix Format - paper on secure and compact message format for mix networks
Sphinx Mix Network Cryptographic Packet Format Specification - specification for Sphinx mix network packet format
Introducing Anonymous Communications slides - notes by George Danezis on properties, threat models, systems & attacks
Anonymous Communications slides at CCC - another overview of anonymous communication systems by George Danezis
What is a Remailer? - anonyomus remailers tutorial building up from basics
Cwtch: Privacy Preserving Infrastructure for Asynchronous,Decentralized, Multi-Party and Metadata Resistant Applications - extension of the Ricochet protocol that provides asynchronous, offline and multi-party metadata resistant messaging

Pluggable Transport - specification initiative to allow applications being used as transports to make network traffic harder to distinguish and block, origins in Tor
So you want to write a Tor pluggable transport (video) - lightning talk about how to write a pluggable transport for Tor
Selected Research Papers in Internet Censorship - meta-list of papers on censorship and resistance thereof

Coercion-Resistance and Receipt-Freeness in Electronic Voting - academic paper that outlines ways to provide coercion-resistance for electronic voting
Coercion-Resistant Electronic Elections - paper on coercion resistance and trusted setup requirement
On-Chain Vote Buying and the Rise of Dark DAOs - on problems of user generated keys and electronic voting

The Sybil Attack - attack on p2p systems from cheap identity generation, requiring some form of logically centralized authority
Tagging Attacks - adversary recognizing traffic by modfiying it in acceptable fashion

Briar - messaging app employing several censorship-resitance techniques, like direct device-to-device comms (bluetooth, wifi), Tor routing
Signal - widely used security-based messaging app with intermediate server and phone based registration, includes voice calls