SR (Selective Router)

SR (Selective Router) is the Central Office that provides the tandem switching of 9-1-1 calls. It controls delivery of the voice call with ANI to the PSAP and provides Selective Routing, Speed Calling, Selective Transfer, Fixed Transfer, and certain maintenance functions for each PSAP.

Also known as:

9-1-1 Selective Routing Tandem

9-1-1 Tandem

E9‑1‑1 (Enhanced 9‑1‑1) Control Office

E9‑1‑1 (Enhanced 9‑1‑1) tandem Office

Relevant NENA Documents

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• NENA-STA-027, NENA E9-1-1 PSAP Equipment Standards
• NENA 03-003, NENA Recommendation for the implementation of Inter-Networking, E9-1-1 Tandem to Tandem