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blind-relay

blind-relay is the TURN-like fallback for peer connections that cannot be established directly — when hole-punching fails (e.g. symmetric NAT). A relay host accepts pairing requests from two peers and forwards UDX stream messages between them over protomux channels. It carries live peer traffic; it does not store or pin data. Because the relayed bytes are the peers’ already-encrypted UDX stream, the relay is “blind” to content. Not to be confused with dht-relay — that bridges the DHT protocol over TCP/WebSocket, a different job.

How it works

See the README for specifics.

A relay host accepts pair requests; two peers that present matching pairing tokens get their UDX stream messages forwarded between them (TURN-style). unpair tears it down.

The README documents the wire protocol (the pair / unpair message fields), not a JS Server/Client API — treat it as the protocol reference; the integration surface is the relay role rather than a documented class.

Gotchas

The hole-punch-failure / symmetric-NAT use case is implied, not named. The README frames it only as “similar to TURN” — it does not say “symmetric NAT” or “when hole-punching fails.” That is the role, but it is our framing, not a README statement.

“Blind = can’t read content” is architectural inference, not a documented guarantee — it follows from the relayed UDX stream being end-to-end encrypted, but the README does not state it. (See the security model.)

It relays streams, it does not store data — distinct from blind-peering / seeders (availability) and from dht-relay (DHT bridging).

Version

blind-relay@1 (active, current — 1.x). Package name matches the repo — no trap. Check the npm registry before pinning.

Sources