STUN / TURN / ICE
STUN discovers address mappings and checks connectivity; TURN relays traffic; ICE chooses candidate pairs. Server access ports and relay media allocations are separate requirements.
Scope: STUN / TURN / ICE — requirements depend on the selected profile.
protocol · Catalog reviewed 2026-09-27
RFC 8489 / RFC 8656 / RFC 8445
NetworkingOpen Standard
Infrastructure Requirements
- Configured STUN/TURN servers, credentials and trust
- reachable candidate pairs and allocated relay ports
- sufficient relay bandwidth.
Network & Physical Requirements
| Port / allocation | Transport | Connection / signal flow | Feature and requirement | Evidence |
|---|---|---|---|---|
| 3478 (default) | TCP/UDP | ICE client → STUN/TURN server | Profile requirement · Core STUN / TURN server access STUN/TURN default server transports | Source checked 2026-09-27 RFC 8656, Section 4: General Overview (TURN URI default ports); Section 6: Allocations |
| 5349 (default) | TCP | TURN client → TURN TLS server | Optional · TURN TLS TURN over TLS TURN TLS default | Source checked 2026-09-27 RFC 8656, Section 4: General Overview (TURN URI default ports); Section 6: Allocations |
| 5349 (default) | UDP | TURN client → TURN DTLS server | Optional · TURN DTLS TURN over DTLS TURN DTLS default where supported | Source checked 2026-09-27 RFC 8656, Section 4: General Overview (TURN URI default ports); Section 6: Allocations |
| Negotiated | UDP | Media peer → Allocated TURN relay | Profile requirement · Core TURN relay allocation / peer media TURN server configured relay range | Source checked 2026-09-27 RFC 8656, Section 4: General Overview (TURN URI default ports); Section 6: Allocations |
Gotchas & IT Notes
- ⚠443 is a common service-specific alternative, not a universal TURN default. Record server URIs, credentials and bounded relay ranges.