NG112 reference
Sip
Structured NG112 reference page.
112 readiness
Policy, location, routing, and response quality connected in one operational model.
SIP and Emergency Signaling
SIP Emergency Signaling
Session Initiation Protocol
SIP is the signaling language for many IP emergency architectures. It sets up sessions, carries headers, negotiates media through SDP and supports transfer, rerouting and callback behavior. Emergency use requires careful treatment of service identity, caller identity, location and fallback.
What it does
SIP can establish emergency voice, text or multimedia sessions and convey or reference location for routing and PSAP handling.
SIP is a common session control protocol between originating networks, ESInet functions and PSAP systems.
How it works
- Creates a session toward an emergency service target.
- Uses headers and bodies to carry identity, service and location context.
- Negotiates media such as voice, RTT or video depending on endpoint and PSAP support.
Key interfaces and protocols
- SIP
- SDP
- SIP Geolocation
- TLS
- RTP/SRTP
Systems it interacts with
- BCF
- ESRP
- ECRF
- PSAP call handling
- Enterprise SBCs
Common failure modes
- Intermediate systems strip emergency location.
- Codec or media negotiation fails.
- Caller identity is not routable for callback.
- Transfer changes lose context.
Implementation considerations
- Trace emergency SIP separately from ordinary calls.
- Test by-value and by-reference location handling.
- Document how emergency callback is preserved.
Standards
- IETF RFC 6442
- IETF RFC 5031
- ETSI TS 103 479
Related NG112 technologies
Related country deployments
No country deployments are listed here until independently verified against official or high-confidence sources.
Related articles
Sources
- RFC 6442: Location Conveyance for SIP - IETF, accessed 2026-08-31
- RFC 5031: A Uniform Resource Name for Emergency and Other Well-Known Services - IETF, accessed 2026-08-31
- RFC 6881: Best Current Practice for Communications Services in Support of Emergency Calling - IETF, accessed 2026-08-31
- ETSI TS 103 479 deliverable directory - ETSI, accessed 2026-08-31
Last verified: 2026-08-31