Open research · AGPL-3.0-or-later
An open protocol for communication that doesn't need a network.
Project Mesh is the research protocol and Rust core underneath Betar: a decentralized, delay-tolerant mesh network that moves encrypted messages phone to phone over Bluetooth LE and Wi-Fi Direct, and, in a later phase, over a backbone of low-cost long-range LoRa radio. No cell tower. No internet service provider. No central server. No personal identifier.
191 Rust tests passing · pre-alpha · no independent security audit yet
Why this exists
Communication that depends on centralized infrastructure fails exactly when that infrastructure is absent, destroyed, or unavailable: in regions with weak or no cellular and fibre coverage, and during disasters that physically knock out towers and power.
Coverage gaps
Hill country, islands, forest and river regions, high valleys: weak, intermittent, or absent cellular and fibre coverage, every day, not just during a crisis.
Disasters
Cyclones, floods, and earthquakes routinely destroy communication infrastructure exactly when people need it most.
Any outage
Towers go down, for whatever reason, for as long as it lasts. A mesh with no fixed infrastructure keeps working through it.
What the protocol does
Transport
A real BLE dual-role GATT driver and a Wi-Fi Direct driver, composed behind one mesh engine. LoRa (India's licence-free 865–868 MHz band) is planned as a longer-range backbone.
Routing
Store-carry-forward: envelope wire format, Bloom-filter gossip summaries, epidemic relay, TTL, per-peer rate limiting, an optional client puzzle against flooding.
Cryptography
Noise XX → Double Ratchet for 1:1 messaging. Classical X3DH plus hybrid post-quantum PQXDH (ML-KEM-1024) for asynchronous first contact. MLS (RFC 9420) for larger groups. Argon2id passphrase-derived channels.
Privacy
Envelope-size padding against relay traffic analysis, encryption at rest, and no personal identifier required to use it at all.
Confidence, stated plainly
191 Rust tests passing. A DTN simulation harness that drives the real relay engine through scripted contact schedules and has already found and fixed a real bug. A wire-parser fuzzing harness for every untrusted-bytes-in parser. A security-review pass. None of this substitutes for an independent audit, which has not happened yet — see the threat model for what is and isn't claimed.
Project Mesh and Betar
Project Mesh is the protocol and the research: identity, encryption, routing, the pieces that make phone-to-phone delivery work without a server. It lives in this repository, together with the whitepaper, the cryptographic design, the threat model, and the Rust core (core/) that implements all of it.
Betar is the reference application built on top of it — messaging, an SOS flow, a disaster bulletin board, a community resource board, and offline maps — the thing most people will actually install. It depends on this repository's core/ as a git submodule, so the protocol has one canonical source regardless of how many applications end up built on it.
Frequently asked
What is Project Mesh?
An open research protocol and Rust core for offline, decentralized mesh communication. Phones (and later, low-cost long-range radio nodes) relay encrypted messages directly to each other over Bluetooth Low Energy and Wi-Fi Direct, with no cell tower, internet connection, or central server involved.
How does Project Mesh relate to Betar?
Project Mesh is the protocol and the Rust core. Betar is the Android application built on top of it. This repository holds the research and the protocol implementation; the app lives in its own repository.
Is Project Mesh open source?
Yes. The code is AGPL-3.0-or-later, this documentation is CC BY-SA 4.0. Anyone may read, build, check and reuse it.
Pre-alpha, no independent security audit yet. Read the threat model before relying on this for anything real.