NG112 reference
Esrp
Structured NG112 reference page.
112 readiness
Policy, location, routing, and response quality connected in one operational model.
Core NG112 Architecture
ESRP
Emergency Services Routing Proxy
The ESRP sits in the emergency session path. It can consult routing information, apply policy, select downstream routes and support alternate routing. It should not be reduced to a static SIP proxy because emergency routing often depends on location quality, service boundaries, PSAP state and failure conditions.
What it does
An ESRP is a SIP-aware emergency routing proxy that helps route an emergency session according to location, service and policy.
The ESRP is a decision and forwarding point between the originating side and the destination PSAP or next routing domain.
How it works
- Receives an emergency SIP session from a trusted interconnect or upstream routing element.
- Uses location and service information to request or apply a routing decision.
- Forwards the session toward the selected PSAP or an alternate route when policy requires.
Key interfaces and protocols
- SIP
- SIP Geolocation
- LoST/ECRF lookup concepts
- Policy and route management
Systems it interacts with
- ECRF
- ESInet
- BCF
- PSAP
- Logging and monitoring
Common failure modes
- Missing or malformed location causes default routing.
- ECRF dependency failure forces fallback.
- Policy tables drift from authoritative GIS/service boundaries.
- Looping or transfer errors between routing domains.
Implementation considerations
- Keep policy routing testable and auditable.
- Separate emergency service selection from ordinary enterprise dial-plan logic.
- Define alternate PSAP behavior before an outage.
Standards
- ETSI TS 103 479
- ETSI TS 103 480
- IETF RFC 6442
- IETF RFC 5222
Related NG112 technologies
Relationship graph
Routing chain: ESRP <-> ECRF <-> LoST <-> PSAP Technology <-> ESInet
Related country deployments
No country deployments are listed here until independently verified against official or high-confidence sources.
Related articles
Sources
- 112: the European emergency number - European Commission, accessed 2026-08-31
- Directive (EU) 2018/1972 establishing the European Electronic Communications Code - European Union, accessed 2026-08-31
- Emergency communications - BEREC, accessed 2026-08-31
- Next Generation 112 and the new Emergency Services Networks Landscape - EENA, accessed 2026-08-31
- ETSI TS 103 479 deliverable directory - ETSI, accessed 2026-08-31
- RFC 5222: LoST: A Location-to-Service Translation Protocol - IETF, accessed 2026-08-31
- RFC 6442: Location Conveyance for SIP - IETF, accessed 2026-08-31
Last verified: 2026-08-31