Switching to VoIP

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Chapter 14: Traditional Apps on the Converged Network

of sending ALI signals to the PSAP. Some VoIP TSPs are working on this problem;

others aren’t planning on offering a solution. This doesn’t mean you can’t reach an

emergency dispatcher with VoIP. It just means that the dispatcher won’t know your

location.

Still, dialing 911 won’t work with most TSPs. You’ll have to reprogram your on-

premises VoIP gateway or IP phone to “translate” 9-1-1 into the full E.164 telephone

number of the PSAP. To make matters worse, it’s not always easy to find out what

this number is. With the ubiquity of 911, these numbers aren’t generally publicized.

You may be able to get only the local fire department’s or police department’s

administrative phone number—and in an emergency, this isn’t who you’re going to

want on the phone. Do the research and find out how to get through to the emer-

gency dispatcher (and not some receptionist) via a 10-digit phone number. Then,

you can program your VoIP devices to connect 911 calls to that number. An exam-

ple of such a configuration is given in Project 14.5.

Project 14.5. Use VoIP Dial-Around to Connect 911 Calls

What you need for this project:

• Asterisk

• VoIP trunk service from an Asterisk-friendly TSP like VoicePulse

This is very much a hack! The FCC and your ...