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ICE, STUN, and TURN
ICE gathers host, server-reflexive, and relayed candidates. STUN and TURN are the tools. The default STUN port is 3478.
Learn in 5 minutes
- Name the three candidate kinds in RFC 8445
- Give the default STUN ports from RFC 8489
- Say what a TURN relay adds
Visual
Ports are the defaults in RFC 8489. Candidate names are from RFC 8445.
Worked example
Sort the candidates Three lines from a study checklist. Match each one to the RFC 8445 name.
- Read the local address.
- Read the mapped address.
- Read the relay address.
Fault
The browser sends REGISTER to port 3478 and waits for 200 OK. The packet that comes back is not SIP.
RFC 8489 assigns 3478 to STUN. RFC 7118 does not assign that port to SIP.
Quiz
Ecosystem
Glossary, sister systems, and the integration seam for this room.
E911 / emergency calling Location has to ride with the call. RFC 6881 is the BCP, RFC 6442 carries location in SIP, and the FCC MLTS page states Kari’s Law and RAY BAUM’s Act obligations for multi-line systems.