P2P first. Relay when needed.
Voice traffic takes the shortest path the network allows. When NAT or firewall policy blocks direct connections, a passive relay forwards ciphertext between endpoints — never holding keys, never inspecting payload.
Architecture réseau
P2P direct ou relais serveur. Dans les deux cas, le serveur est aveugle.
Mode A
P2P Direct
Appelant
Peer
Lorsque le NAT le permet. Latence et coût minimaux.
Mode B
Mode Relais
Appelant
Peer
Lorsque les réseaux bloquent le P2P. Le relais transmet uniquement du ciphertext.
Le serveur ne détient jamais les clés
Les endpoints dérivent le secret de session
ML-KEM-1024 + AES-GCM
Même cryptographie dans les deux modes
Sélection automatique
Essaie d'abord le P2P, bascule en douceur
Le relais est un transmetteur passif de paquets. Il ne peut ni lire, ni modifier, ni rejouer le flux de ciphertext — même sous contrainte.
NAT traversal mechanics
Most home and enterprise networks sit behind NAT or strict firewalls that block inbound UDP. Our client probes peer reachability with ICE-style candidate gathering, then opens a direct path when both endpoints can be reached.
- Candidate gathering on host, server-reflexive and relayed transports
- Symmetric NAT detection falls back to relay automatically
- No external STUN dependency on operator-controlled deployments
Fallback logic
The session always negotiates the same post-quantum key. Network mode is chosen by reachability, not by trust: if P2P fails, the relay takes over within the same RTT budget. The cryptographic envelope does not change.
- P2P attempt window: ≤ 800 ms before relay is engaged
- Mid-call switch supported when network conditions change
- Same ML-KEM-1024 session secret in both modes
No metadata retention
The relay forwards packets and discards them. No call detail records, no call duration logs, no participant graphs. The only state retained is short-lived NAT mapping required to route the next packet.
- No CDRs, no per-call billing logs, no participant graph stored
- Packet metadata kept only for the lifetime of the NAT mapping
- Operator-deployable: relay can run inside your own datacenter
Need a private relay deployment?
Air-gapped, sovereign, on-premise — your operators, your network, your control plane.
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