Which term describes the mechanism that directs 9-1-1 calls to the correct Public Safety Answering Point (PSAP) based on routing criteria?

Which term describes the mechanism that directs 9-1-1 calls to the correct Public Safety Answering Point (PSAP) based on routing criteria?

• A. Dual Tone Multi-Frequency
• B. Selective Routing
• C. Automatic Location Identification (ALI)
• D. Local Transport Area

Answer: (B)

Selective routing is the mechanism that directs 9-1-1 calls to the correct PSAP by using routing tables tied to the caller’s location. When a call arrives, the switch uses location data and predefined routing mappings to forward the call to the PSAP responsible for that area, ensuring the right agency handles the incident and has the appropriate information to dispatch. Automatic Location Identification provides the address data after routing but doesn’t determine the destination itself; DTMF is just keypad tone signaling, not routing; Local Transport Area is a transport-region construct, not the routing mechanism for PSAPs.

Selective routing is the mechanism that directs 9-1-1 calls to the correct PSAP by using routing tables tied to the caller’s location. When a call arrives, the switch uses location data and predefined routing mappings to forward the call to the PSAP responsible for that area, ensuring the right agency handles the incident and has the appropriate information to dispatch. Automatic Location Identification provides the address data after routing but doesn’t determine the destination itself; DTMF is just keypad tone signaling, not routing; Local Transport Area is a transport-region construct, not the routing mechanism for PSAPs.