Federation Protocol

Federation in the archipelago is peer-to-peer, authenticated, and narrated as weather. Under the hood, realms communicate over QUIC with mutual TLS, each side presenting its Ed25519 realm certificate. The protocol is called porthmos — Greek for strait or passage.

A federation link (a “lane” in player-facing terms) is established when both realms declare each other as peers in their configuration. The handshake exchanges realm metadata, trust policies, and signal attenuation parameters. Once established, signals flow bidirectionally — attenuated by the configured distance and filtered by each realm’s customs policy.

The protocol is intentionally simple. Signals are CBOR-encoded, content-addressed with SHA-256, and signed by the originating realm. A receiving realm verifies the signature, applies its attenuation curve, and delivers the signal to any entity within earshot. If verification fails, the signal is silently dropped — fog swallows it, as far as the player knows.