Technical Specifications
The engineering foundations — protocols, cryptography, and wire formats.
Protocol-74 Revision E
ActiveThe authoritative specification. Glacier V2 transport, Negentropy reconciliation, ESP-NOW framing, Lantern/Spore architectures, hardware BOMs.
Key Ceremony
ActiveFour-phase authentication flow. GPS → Geohash → Morton Code → Blake3 KDF → XChaCha20-Poly1305. The ceremony gradient: tap, GPS match, QR decrypt.
Cross-Platform Crypto
ActiveTypeScript (PWA) and Go (CLI) must produce identical output. Morton code interleaving, Blake3 derive_key mode, test vectors for coordinate parity.
QR Payload v2
ActiveEncryption format for deployment QR codes. URL fragment encoding (zero server knowledge), nonce derivation, XChaCha20-Poly1305 payload format.
Protocol Constants
| Constant | Value | Notes |
|---|---|---|
| Network ID | 0x444D5A53 | "SMZD" little-endian |
| Max Payload | 250 bytes | ESP-NOW hardware limit |
| Max Message | 2048 bytes | Split via Glacier protocol |
| Short Hash | 6 bytes | Bloom filter entries |
| Max Messages | 750/throwie | LittleFS storage |
| KDF Context | smzd:ck:1 | JOSE-style, hard-coded |
Crypto Stack
| Primitive | Library | Usage |
|---|---|---|
| Blake3 | @noble/hashes | KDF, content hashing |
| XChaCha20-Poly1305 | @noble/ciphers | Payload encryption |
| X25519 | @noble/curves | Key exchange |
| Ed25519 | @noble/curves | Signatures (future) |
Frame Types
| Byte | Name | Purpose |
|---|---|---|
| 0x42 | Beacon | Mule announce |
| 0x4D | Manifest | Throwie inventory |
| 0x52 | Request | Pull messages |
| 0x43 | Chunk | Message data |