Right now I use BRI for the ISDN and regular copper for the incoming
analog
modem calls. I kept hearing of a provvider that always connect at 31200
and
33600. So i decided to give it a call with my modem and sure enough,
connected
at 33600 and 31200 almost everytime. Found out heuses and Acend 4000
max, I guess
that is why he gets good connections?
>
> > ports. I am thinking about going T1 not only to keep up with the
> > "Possible" technology of 56k since it only works if there is one
> > conversion in the line.
>
> This is true- but I wouldn't let the possibility of 56K 'fake digital'
> modems affect the decision to change how your lines come in.
>
> > What is the difference between channelized t1 and regular T1.
> >
> > Which is better?
>
> Physically they are all the same. Logically they are all 24 channels
> of 64000 bits each.
>
> There are three different common ways of provisioning service over a T1,
> in increasing order of (usual) price they are:
>
Any bandwidth loss for signaling here???
> 1. leased line 'clear channel' data.
> This is the usual 1.5Mbps line between internet sites.
> 2. Channelized T1
> This provides 24 channels of 56K digitized audio (the
> missing 8K is used for signalling). This is what USR
> 'Total Control' racks and some PBX systems use.
> 3. Primary Rate ISDN
> This is 23 'B' channels of 64K data, with the 24th channel
> being the 'D' channel signalling. Each channel can be used
> for pure data or digitized audio from analog calls.
>
> > Does the PM3 support both?
>
> I believe currently incoming calls are only accepted with PRI, but
> channelized T1 is in the works.
Funny, a salesman at ascend told me that the T1 on a max4000
will do ISDN, Hmm somewhat suspicious huh?
>
> > What is a rough estimate of a a T1 with 24 dialin numbers from
> > bellsouth? Channelized or not whichever apply?
>
> You need at least channelized to accept calls from your users.
> I've done ISDN consulting around the Midwest, but it's been mostly in
> Ameritech's service area, where you're looking at some really hefty
> rates.
>
> Take a look at Dan Kegel's ISDN page for links to price and hardware info:
>
> http://alumni.caltech.edu/~dank/isdn/
>
> > Can either T1 do ISDN? So the customer calls one phone number and gets
> > either ISDN or Analog when dialing in?
>
> Of the three, only PRI can do ISDN. It also can do analog.
> Channelized can do analog only.
>
> Either should be able to do new '56K' fake-digital modems.
>
> > Does the PM3 do ISDN on the 24 channels without any modem cards. In
> > other words the modem card are only if you are going to support analog
> > calls.
>
> Yes.
>
> > conecerning the PM3 Do you have to provision the t1 so that lets say 8
> > are for analog and 16 are for ISDN, so if 8 analog users are on and
> > another call will it get a ninth channel that is not used or do you have
> > to specify which are anolog and which are digital.
>
> PRI gives 23 channels...
>
> The PM-3 itself does not require that you pick- it might not even be possible?
>
> Some telcos do require that you specify which DNs are analog and which
> digital in order to set up hunt groups.
>
> If you install 8 modems, then from one PRI you can have up to 23 total
> calls, if all 8 modems are in use, then 9th modem caller will be blocked.
>
> > I would appreciate a little light on the subject.