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- Newsgroups: comp.protocols.nfs,comp.dcom.isdn
- Path: sparky!uunet!mcsun!sunic!ugle.unit.no!humpty.edb.tih.no!lumina.edb.tih.no!ketil
- From: ketil@edb.tih.no (Ketil Albertsen,TIH)
- Subject: Re: PC-NFS PPP Serial/ISDN driver wanted
- Message-ID: <1993Jan25.153121.20067W@lumina.edb.tih.no>
- Sender: ketil@edb.tih.no (Ketil Albertsen,TIH)
- Organization: T I H / T I S I P
- References: <2936706683.1.p00136@psilink.com>
- Posting-Front-End: Winix Conference v 92.05.15 1.20 (running under MS-Windows)
- Date: Mon, 25 Jan 1993 15:31:09 GMT
- Lines: 63
-
- In article <2936706683.1.p00136@psilink.com>, "Bob Larribeau"
- <p00136@psilink.com> writes:
-
- >In the U.S. (unlike most of the rest of the world) the NT1 is customer
- >equipment and not network equipment. It is the customer's
- >responsibility to purchase and install the NT1.
- >
- >The reason for having a U interace in the ISDN bridge is that it can
- >reduce cost by eliminating the need for the U interface to T interface
- >conversion and then the T interface to Ethernet conversion by converting
- >directly from the U interface to Ethernet.
- >
- >Note that this is not necessarily the same as integrating the bridge
- >with an NT1. NT1s have an S/T inteface and support the passive bus.
- >The U interface bridge would not require this function.
- >
- >The primary advantage of having an NT1 is that it permits support for
- >passive bus and the ability to connect multiple devices on an ISDN line.
- >However given the limitations of NI-1 in supporting B channel
- >contention, this is not a strong reason. These limitations are supposed
- >to disappear with NI-2.
- >
- >In the U.S. there are ISDN telephones and TAs with U interfaces. It
- >does represent the lowest cost for connecting to an ISDN line. A voice
- >only, U interface ISDN telephone is in the $200 price range.
-
- Pity me. I am a European. I can't select from a whole crowd of Ether-to-
- U-variant-1 and Ether-to-U-variant-2 and ... praying to God that I'll
- get the right one THIS time. Whatever Ether-to-S/T I buy, it will fit
- into my ISDN network. How boring. How unimaginative. How unchallenging.
-
- Pity me. If in the future the phone company replaces the copper U
- with a fiber based U, I am not forced to stimulate economy by buying
- a new Ether-to-U bridge - the old one still works. The economy might
- come to a standstill that way.
-
- Pity me. On my S/T connection, I hook up fax machines, phones, PC ISDN
- cards and other equipment side by side, rather than ordering a whole
- bunch of ISDN lines, one for each. I must have misunderstood the "IS"
- in "ISDN" - the idea is to do it on different but similar connections,
- isn't it?
-
- Pity me. On my ISDN connection I can transfer sound and files and E-mail
- and what have you, I do not have a dedicated voice solution. I probably
- have a very inefficient solution.
-
- Pity me. The standard components of my standard ISDN system honors the
- ISDN standard. So if I want non-standard (with respect to ISDN) equipment
- to interface with a unstandardized U network connection, in *my* world
- there is none of ISDN left. In *your* world, you can continue calling it
- ISDN although there is no place in the system where actual ISDN standards
- are employed fully, no place where equipment that 100% follows the ISDN
- standards can be plugged in.
-
- Pity me. I cannot get a standard ISDN phone with all the added ISDN
- functionality and flexibility as cheap as your socalled ISDN phone
- that really has nothing to do with ISDN. I will have to pay a little
- bit more (at least until the volume comes up because in Europe, we
- will all be using the same standard), but I will get A LOT more.
-
- Or maybe I don't need all that pity, after all...
-
- :-) :-) :-) :-) :-) :-) :-) :-) (-: (-: (-: (-: (-: (-: (-: (-:
-