<oembed><type>rich</type><version>1.0</version><title>Keychat wrote</title><author_name>Keychat (npub1h0…srwx8)</author_name><author_url>https://nostr.now/npub1h0uj825jgcr9lzxyp37ehasuenq070707pj63je07n8mkcsg3u0qnsrwx8</author_url><provider_name>njump</provider_name><provider_url>https://nostr.now</provider_url><html>Keet uses the Holepunch stack—not WebRTC—for its real-time voice calls. In a one-to-one call the connection likewise falls into three logical stages:&#xA;&#xA;1 · Peer-discovery exchange&#xA;&#xA;Each endpoint relies on HyperDHT ( Distributed Hash Table) to locate the other party:&#xA;&#xA;The caller joins the network with the callee’s 32-byte Ed25519 public key.&#xA;&#xA;Nearby DHT nodes return the latest announce record published by that key—essentially “I’m online at 203.0.113.7:54567”.&#xA;&#xA;A short-lived, signed invitation token proves the request really comes from the owner of the calling key, preventing spam.&#xA;&#xA;No central signaling server is involved; the DHT itself is the rendez-vous layer.&#xA;&#xA;2 · Distributed hole-punch — DHP → direct connection&#xA;&#xA;The two devices attempt to break through their NATs with DHP (Distributed Hole Punching) and then talk over UDX (Ultra-Datagram eXchange):&#xA;&#xA;Each side enlists several random DHT peers as hole-punch helpers—they play the same role that STUN servers do in WebRTC but are fully decentralized.&#xA;&#xA;Both endpoints fire simultaneous UDX probes at every candidate (IP:port) they learn.&#xA;&#xA;As soon as one path succeeds, a one-round-trip Noise_XX handshake derives a session key, and encrypted audio frames start flowing directly between devices.&#xA;&#xA;In residential or mobile networks this succeeds ~70 %–80 % of the time, giving a pure P2P (peer-to-peer) path with minimal latency—no relay, no bandwidth fees.&#xA;&#xA;3 · Volunteer relay fallback&#xA;&#xA;If symmetric NAT (Network Address Translation), CGNAT (Carrier-Grade NAT), or a strict firewall blocks every hole-punch attempt:&#xA;Keet asks nearby peers whether any is willing to act as a relay for this call.&#xA;&#xA;If at least one agrees, the audio stream is tunneled through that peer—still encrypted end-to-end by Noise—so neither relay nor network can eavesdrop.&#xA;&#xA;When no volunteer relay is available, the call fails; Keet has no equivalent to TURN (Traversal Using Relays around NAT) hosted in a central data-center.&#xA;&#xA;nostr:nevent1qvzqqqqqqypzpwleyw4fy3sxt7yvgrran0mpenxqlululur94r9jlax0hd3q3rc7qy88wumn8ghj7mn0wvhxcmmv9uq32amnwvaz7tmjv4kxz7fwv3sk6atn9e5k7tcqypvwqh84uq76vdjhaa9ekn4tt0trwuw2kkc5htsxz2jasezmmcht60p280p</html></oembed>