Jonathan de Boyne Pollard,

25-Aug-99 08:33:12, Jonathan de Boyne Pollard wrote to Barry Geller
          Subject: PCI(?) modem and OS/2 Warp 4

I changed the Subject in this thread because the topic has changed and the new
topic was covered in great detail from med to end of Feb-99 in the OS2 echo
with the Subject: USR internal Sportster 56

 JdBP>>> I did consider ISDN, but again, that would limit whom I could place
 JdBP>>> calls to.  I couldn't send Jack Stein a crash netmail if I had an
 JdBP>>> ISDN connection, for example.  (-:

 BG>> Actually, you can.  USR/3-COM's I-Modem will allow you to do
 BG>> Analog V90/V34 calls originating on the digital connection, I
 BG>> beleive.

Yes, the USR Courier I-Modem with an integrated Courier V.Everything.

But at this point there is likely to be some confusion if we use "USR/3Com"
implying there is only 1 product, instead of separate the older USR product
(Courier I-Modem) from the newer different (cheaper) 3Com products.

http://www.3com.com/products/isdn.html

Courier I-modem ISDN with integrated V.Everything data/fax/modem
http://www.3com.com/products/dsheets/400369.html

pricewatch.com
3COM courier i-modem w/isdn/v.34 ext. w/analog device port $244
BUY.COM 888-880-1030

---
3ComImpact IQ External ISDN Modem
http://www.3com.com/products/dsheets/400232.html

pricewatch.com
3COM 3C882 IMPACT IQ EXT 230.4K ISDN MODEM PC/MAC $165 Firesale.com
---                                                               

Not to mention a new Sportster ISDN WinModem.  

 JdBP> One thing that concerns me about ISDN is whether or not the modem has
 JdBP> to be powered on all of the time.

Yes it does.

Look at it this way.  On a normal Dialup line the TeleCo provides the battery
power and conversion from analog to digital.  On ISDN lines the I-Modem does
that.  So essentially the I-Modem can provide an analog device a connection
to the digital lines.  So in a way the I-Modem is like moving the digital
portion of the TeleCo C.O. directly to your house or business.  It's a little
more complex than that, but that's a simple analogy.

 JdBP> This is of most concern when it comes to making voice calls.  If I
 JdBP> went for ISDN, I'd need to be able to make voice calls at the same
 JdBP> time, which I gather can be done using one of the "B" channels.  True,
 JdBP> some ISDN systems have an external socket for an ordinary voice
 JdBP> telephone (Does the USR Courier I-modem have this, anyone?),

Yes, the USR Courier I-Modem with an integrated Courier V.Everything
connected to digital ISDN lines can support analog devices.  Both
internally as in the Courier V.Everything and externally with
another modem or voice phone connected to the pass-through port.

 JdBP> but it seems to me that logically the ISDN modem has to be
 JdBP> continuously powered if I want to make voice calls over the ISDN line

Yes it does.

 JdBP> The important thing that I'm concerned with is being able to make (and
 JdBP> receive) voice calls at the same time as ordinary data calls.  If, in
 JdBP> order to achieve this, ISDN requires that the PC, or modem, be
 JdBP> continually powered,

Yes it does.

 JdBP> then it may turn out to be cheaper just to rent a second voice line
 JdBP> instead.

Yes it could be a lot cheaper.  Another voice line in addition to ISDN would
actually be 3 phone numbers.  This gets complex considering that you can use 1
of the ISDN "B" channels for voice.

--- Excerpt ISDN_FAQ.ZIP ---
A Basic Rate Interface (BRI) is two 64K bearer ("B") channels and a single
delta ("D") channel.  The B channels are used for voice or data, and the D
channel is used for signaling and/or X.25 packet networking.  This is the
variety most likely to be found in residential service.
--- End Quote ---

If I understand ISDN correctly, the common modes of operation would be voice
on the pass-through port of 1 of the "B" channels, with it's own phone number,
with the integrated Courier V.Everything (V.90) on the other "B" channel, with
another phone number, that can send or receive data calls like any ordinary
modem; OR full ISDN digital data that bundles both "B" channels.

BUT...!
Here in the US the TeleCo assumes anytime we use ISDN that we can make use of
the full bandwidth, so we will get billed for it all at the higher "data rate"
fees for LD rather than be able to take advantage of the lower analog fees,
even if we only use 1 channel, such as for V.90, or the other channel, such as
for voice.  Thus we will pay more for using ISDN for anything other than ISDN.
The TeleCo recommends having a separate analog line for voice and/or V.90 and
using a non-ISDN modem whenever possible to save on our phone bill.

So it is not a question of the technological capability to send and receive
ordinary V.90 and make or receive voice calls all at the same time with ISDN.
The only time ISDN is economical is when it is being used only for 2 bundled
"B" channels for data.  Otherwise the higher fees for that service will
quickly amount to more than the expense for a separate analog (voice) line.
Thus unless your ISDN usage justifies the expense of the ISDN line and the
I-Modem in addition to another voice line and another V.90 modem, then you
could be much better off with just an ordinary V.90 and voice line, without
any ISDN.

In my case (not just because of the BBS) it is very important that my voice
line is not tied up for any length of time for data, such as browsing the net.
So I have 1 line for data and another for voice.  Here, if it were available,
ISDN would cost $25 more than a single voice line.  So I could trade in both
of my existing lines and only have to pay about $5-10 more for ISDN on my
basic bill.  But the increased fees for all LD V.90 and voice calls would make
my total bill go sky high.

     Thanks and Good Luck,        Andy Roberts
                                  andy@shentel.net
--- Terminate 5.00/Pro*at