Miscellany

[13:38] <tristanbob> we have fire-alarms, public broadcasting systems, building automation devices, credit card modems, fax, and more that will need copper analog lines
[13:38] <tristanbob> jsmith: that is huge
[13:38] <jsmith> obviously that wasn't handled by a single Asterisk box
[13:38] <tristanbob> do we just get ATA for that type of device?  I am not very smart about telephony
[13:38] <jsmith> OK, you want to keep things like fax and credit-card machines out of Asterisk... they'll cause you nothing but problems if you try to run those off of Asterisk
[13:38] <jsmith> (Just trust me)
[13:38] <jsmith> For things like PA systems, you can buy Digium cards that have either FXO ports (for plugging phone lines from the telco into) or FXS ports (for plugging analog phones, etc. into)
[13:38] <tristanbob> jsmith: how do you keep those off of asterisk?  use a smaller TDM PBX?
[13:38] <jsmith> Just put them on raw analog lines from the telco
[13:38] <jsmith> Fax & modems = headaches
[13:38] *** Channel modes: topic protection, no messages from outside, no colors allowed
[13:38] *** This channel was created on 12/31/69 17:00:00.
[13:39] <tristanbob> I see - so they can give us dozens of analog lines?  I always thought they used a T1 if it was more than a few lines
[13:43] <jsmith> Yeah, for your normal voice calls, you'll want to use T1 lines
[13:43] <jsmith> But for things like PA systems and such, you may need some analog connections as well
[13:44] <tristanbob> I wonder if that is how we currently do our firealarms... (I'll try to find out)
[13:45] <tristanbob> jsmith: do you think qwest can offer numbers from our block of DIDs if we have both types (t1 and analog)?
[13:46] <jsmith> tristanbob: Probably
[13:48] <tristanbob> jsmith: I was just chatting in the #cisco channel and they also recommend analog - so it is a general VOIP issue, not just Asterisk specific (but you already knew that)
[13:49] <jsmith> Yup
[14:03] <tensai> jsmith: 29 T1s? I sure hope there was a DS3 in that mix. can you imagine doing that with analog lines instead?
[14:03] [Away] You are not marked as being away.
[14:04] <jsmith> tensai: DS3 + an extra T1
[14:10] <billyjean> tristanbob: you can do this to pull out analog lines if you want...
[14:10] <billyjean> qwest --> t1 --> channel bank --> break out analog lines and pass on the T1 to Digium card or something
[14:11] <billyjean> cbrown who never says anything in this channel is very familiar with old school telco solutions
[14:15] <tensai> jsmith: I'm not sure how big it was, but I did see an old old PBX which couldn't handle T1s at all so all their lines were delivered over analog DIDs
[14:16] <tensai> and they had a lot. I would estimate 100-200 lines. I did not envy their phone admin.
[14:16] <jsmith> tensai: Yeah, that's just sick and twisted
[14:16] <jsmith> billyjean: Yeah... I've done a lot of channel-bank solutions as well
[14:17] <tensai> they were supposed to have upgraded it last winter. for their sake, I hope so
[14:18] <tensai> so all the T1s I've seen were set up to deliver calls on whatever timeslot the switch felt like. is it possible to dedicate a certain timeslot to a single line?
[14:18] <tensai> seems like you'd have to in order to split it with a channel bank like that
[14:18] <jsmith> Nope, I don't think so
[14:18] <tensai> how does that work then?
[14:19] <jsmith> You have PRI lines (fancy T1's with lots of extra signaling on the 24th time-slot) coming into Asterisk, and then going out from Asterisk on another T1 port to the channel bank.
[14:19] <jsmith> When the call comes into Asterisk, it carries along a piece of information called the DNIS digits.
[14:20] <jsmith> This is usually a 4- or 10-digit number, which *usually* (but not always) matches up with the number that was dialed.