From: woody@ucscb.UCSC.EDU (Bill Woodcock)
Newsgroups: ba.internet
Subject: Re: ISDN, PacBell, phone charges, USENET and you
Date: 27 Sep 1992 04:46:57 GMT
Organization: University of California; Santa Cruz
NNTP-Posting-Host: ucscb.ucsc.edu


                                             Saturday, September 26, 1992
    
          jordan@IMSI.COM (Jordan Hayes) writes:
        > Say I had a Sparc 10 that has an ISDN interface built in.  
        > What else would I need at my house to get to the network, 
        > or would it just plug into the wall?
    
    You'd need an NT1, or "network terminator one."  It's kind of like a
    tiny PBX.  It's what converts the DSS1 (digital subscriber signal one)
    to ISDN.  (I may be misusing the term DSS1.  It may refer specifically
    to the signaling protocol stack, rather than the format of the data as
    it travels from the CO to the subscriber.)  The DSS1 signal runs on a
    single pair, while ISDN requires two pairs, plus power on the other
    two.  Both AT&T and NT make NT1s, and each company's product is
    interoperable with service from the competitor's switches, but I don't
    think they're interoperable with each other's station and terminal
    equipment.  I think they're in the $300-$500, depending largely on how
    you want to be able to access the D channel.  I may be wrong on a lit
    of this, though.
    
          dtlai@srv.PacBell.COM (Danh Lai) said:
        > Package C = 2B+1D : This package is the ultimate offering 
        > of BRI-Centrex IS. You can used any of the 2B channels for
        > either voice or data and X.25 packet data on the D channel.
    
          eric@telebit.com (Eric Smith) writes:
        > This doesn't allow you to use both B channels for voice
        > simultaneously.  You can only use one at a time for voice.
        > I have no idea why they tariffed it that way [perhaps] so 
        > they can still sell you custom annoyance features like
        > call waiting and three way calling.
    
    I don't believe this last is correct, in reference to package three.
    I've heard exactly the same limitations referred to, but connected
    with packages 1 and 2, which really are designed for single-line voice use.
    
    One neat feature of even packages 1 and 2 is third-party dropout.  You
    can, of course, only talk to one person at a time, but you can have as
    many people on hold as you want, and _you can let them talk to EACH
    OTHER._  Ha.  Had to emphasize that.  Another interesting service
    PacBell is going to be offering, in response to a problem with ISDN,
    is music on hold.  Since the subscriber can't access people who are on
    hold, the subscriber can't supply MOH. Thus it has to be done at the
    switch, and both NT and AT&T provide that feature.  A PacBell ISDN
    product manager describing the proposed service to me said that
    subscribers would have their choice of "three channels of Muzak, all
    of which sound exactly the same."
  
                             -Bill Woodcock

________________________________________________________________________________
bill woodcock  woody@zocalo.com  woody@applelink.apple.com  woody@ucscb.ucsc.edu

Newsgroups: ba.internet