Comcast is a BROADBAND CABLE COMPANY that decided to get into the phone biz. And like so many other CLECs, they've not done their homework.
Home phones are a lousy way to determine the worthiness of a line as they seem to tolerate all kinds of sloppiness...squarewave rings, blah blah.
Comcast has a protocol called XMPP. I understand that their cable TV customers can get Caller ID screen pops while they're watching the tube. But let's be honest, that's not Bellcore FSK. So while it may work on a Trimline, it's not exactly a surprise that the PACS may not like it.
NOT the fault of the Partner ACS. Period.
Allow me to quote a similar tale that I heard from Touchtone Tommy:
"A call would ring in, CID would show on the display, they would pick up the handset, the ringing on the phone would stop, the line turns green, but no one would be there. Put the handset back in the cradle, and the line would start ringing again, but this time NO CID. Lift the handset and the caller would be there. The entire time the caller was hearing ringback.
Did the standard troubleshooting, swap the lines from CO1 to CO2, see if the problem follows, happened mostly first thing in the morning for the customer, but I could never duplicate it.
We put a single line phone on the CO side ahead of the Partner, and asked them to answer on that when they answered on the Partner and no one was there. Wierd thing was that while the 2500 was connected, that line never experienced the problem!! It was on CO1, it was fine but they had the problem on CO2. Moved the 2500 to CO2, and the problem came back to CO1."
He concluded that the CO was providing the incorrect impedance which, by the way, plays a role in proper FSK signaling. Booyah.
