Re: answer supervision on CT1

Tim Hodges, Triangle Telephone Cooperative (7thodges@3rivers.net)
Fri, 23 May 1997 10:50:13 -0600

At 09:36 AM 5/23/97 -0600, I wrote:
>I have PM3's on CT1 lines running ComOS3.5.1b8. When calling from local
>telephone numbers they work great. If I try calling them over long distance
>carriers, the modems either fail to negoiate or the call is terminated after
>90 secs. The telephone guy that is helping me says that is because
>the PMs are not completing answer supervision. The long distance
>carriers (AT&T, MCI, Sprint) don't like this. So they either dont
>actually complete the call, or cut it off after a short time.
>
>What can anyone tell me about answer supervision and what I need to change?
>
>Tim Hodges
>7thodges@3rivers.net
>Triangle Telephone Cooperative
>
>

We found the problem. It is a bit of telephone network esoterica having
to do with feature bits on telephone trunks. Every trunk has a setting
for "charge/no charge" calls. Our trunks from the remote POP were set to
'no charge' because we want our customers to be able to call us for free.
When I called via AT&T, the AT&T switch would see this 'no charge' bit and
not allow the call because it doesn't want to lose the toll revenue.

The eventual solution will be the installation of an FXO/FXS circuit into
the remote POP.

Thanks for everyones help.

Tim Hodges
7twh@3rivers.net