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NOTE: For more details, refer to:
The TBB default Emergency 911 service is tied to your Primary Number NPA-NXX (area code - exchange), and not to your billing address. Regardless of where you are physically located, 911 service will currently always connect you to an emergency call center, unless you meet the requirements for and have received Enhanced 9-1-1 service, in which case you will be routed directly to the 911 dispatcher.

Most TBB subscribers have a number in the 911 PSAP jurisdiction in which they live and have E911 service, so for the majority of subscribers this discussion is not an issue.

However, if you do not reside in the local calling area of your Primary TBB number, or if you use your TBB equipment from multiple locations, there are technical and administrative issues to resolve before VoIP 911 service can be routed and handled correctly by 911 centers.

How 911 currently works
Generally, 911 works where your call is routed to a 911 PSAP - (Public Safety Answering Point) - aka 911 dispatcher:

  • With Enhanced 9-1-1, the PSAP uses your call's ANI data to lookup a database (DB) for your address. The ANI is actually your TBB number which is always transmitted when you dial a number - it is also used for billing purposes. ANI is used because it is independent of Caller ID (CLI), which may or may not be blocked depending on your account's settings.

  • The DB address info is populated from the various Telcos - including Primus - and this is done when you get a new phone number, through the normal telephone number provisioning systems in place already (most likely through AllStream for TBB).

    FOR EXAMPLE: If you live in Toronto and have 416 TBB phone number, your 911 call will go right away to the Toronto 911 center and will transmit your CallerID. If you live in Oakville (905), and have a 416 number, your 911 call will still be forwarded to the Toronto 911 center, which may or may not be able to transfer you (or your request) to the appropriate Oakville 911 center or help you in any other way.

    The issues
    Currently, your call cannot simply be routed to another PSAP (for your street address) for the following reasons:

  • Not all PSAPS can handle or tolerate out of area code numbers that are routed to it.

  • There is no standard mechanism for PSAPs to lookup an out-of-town ANI (your TBB #). Some PSAPs search the internet etc, but this slows down PSAP service for everyone; which is a detrimental side-effect.

  • How does an Ottawa address get populated in the Ottawa 911 DB automatically - without an Ottawa telephone number ?

  • Even if Primus can route the 911 call to your local 911 PSAP, what ANI would they use? They cannot use a fake Primus ANI. Using your real ANI (TBB number) may break some PSAPs which cannot handle out-of-town ANIs.

    The solution
    With the new CRTC requirements, all TBB services are potentially nomadic (not fixed, as in Cable VoIP), so all 911 calls have to be routed to a special call center. This centre, in turn, will connect the call to the appropriate 911 PSAP.

    This means that there is 911-like service for those with phone numbers outside of their local exchange or people on the move. On a flip side, this also means a (CRTC) legislated downgrade of service to the majority of customers who have their phone number within their local exchange. Instead of going directly to their local 911 PSAP, their 911 calls first go to an intermediate call center, before being routed through - losing a few seconds of valuable time!

    Primus has received permission to have native/non-nomadic TBB users continue to connect directly to the local 911 PSAP (i.e. without the intermediate call center)- where the Primary Number is within their residential 911 calling area.

    Expand got feedback?

    by canoe See Profile edited by Styvas See Profile
    last modified: 2006-10-16 01:15:42