Re: ISDN on Channelized T1? (fwd)

Donald Reiher (dreiher@compsupport.com)
Tue, 29 Jul 1997 18:33:42 GMT

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-> Once upon a time Donald Reiher shaped the electrons to say...
-> >That is correct. But we were under the impression that CT1 could not
-> >support ISDN. Is DOV technically ISDN or not? Is it cheaper than
-> ISDN?

-> This is what is called technological slight of hand...

-> Technically a channelized T1 line is NOT capable of handling ISDN.

-> HOWEVER, data is data. Channelized T1 lines CAN handle voice calls.
-> And an ISDN DOSBS call is treated by the telco like a voice call. So
-> you are taking advantage of this little tidbit to route call that
-> originates as ISDN onto a non-ISDN line. You don't need a D channel
-> to *receive* an ISDN DOSBS call, just to make one. So all we are
-> doing is taking that 56K data stream and decoding it just as we would
-> if it were on a PRI.

-> Now, you *do* need full ISDN service (a PRI) to accept ISDN DATA calls.
-> Channelized T1 just lets you support a very strict subset of ISDN -
-> purely 56K ISDN DOSBS calls.

-> >If so, then why haven't I heard about it? I called BA Infospeed
-> yesterday, >and the person said their was no such thing as DOV. Are
-> they morons or

-> You cannot *order* DOV. It isn't a service. It is a protocol used
-> by the calling TA.

-> In any case it it is offically called DOSBS - not DOV.

-> What you need to do on the client end is order the BRI ISDN line with
-> speech capabilities. Do NOT order a data-only BRI or you can't make a
-> DOSBS call - period.

-> You still need to buy BRI service - no way around that. All DOSBS
-> allows you to do is make the 56K DOSBS calls at a *voice* tariff
-> instead of a *data* tariff. In some areas there is a major
-> difference, in others there is no difference at all and DOSBS is
-> pointless. (Well, from the client end - sometimes there is still a
-> difference on the server end cost of PRI versus chanT1.)

After several dozen calls to the phone company, I finally found a tech
support guy who admitted that Pac Bell has separate tariffs. Bell
Atlantic does not. I have a "Generic M" ISDN line which includes voice
capabilites (easy to check. . . just plug a phone in the pots jacks).
Therefore, when I call a CT1 using 56K, I take it I am making a DOSBS
call, only since the voice tariff is the same as the data tariff, it
really makes no difference.

By the way. . . thanks for the help. It is so rare in this business to
find someone who actually knows what they are talking about.