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- Newsgroups: comp.dcom.isdn
- Path: sparky!uunet!wupost!howland.reston.ans.net!bogus.sura.net!darwin.sura.net!cos!cos!bob1
- From: bob1@cos.com (Bob Blackshaw)
- Subject: Re: Newbie Q
- Message-ID: <bob1.726244625@cos>
- Organization: Corporation for Open Systems
- References: <24677@galaxy.ucr.edu>
- Distribution: world
- Date: Tue, 5 Jan 1993 14:37:05 GMT
- Lines: 43
-
- In <24677@galaxy.ucr.edu> rogue@ucrengr.ucr.edu (ed zeamba) writes:
-
- >Ahhh.. if you can excuse an ignorant but enthusiactic student of
- >dcom asking a dumb question... :)
-
- >What exactly is ISDN?
-
- >simple enough eh?
-
- Hmm? A Canadian at UC Riverside?
-
- To put ISDN in very simple terms, it does two basic things. Firstly,
- it extends digital transmission right out to the user over the local
- loop - in one interface (Basic Rate I/F or BRI), the user gets two
- 64 kbit/s lines. In the second interface (Primary Rate I/F or PRI),
- the user gets 23 64 kbit/s lines or 30 64 kbit/s lines - depends
- on the carrier system used.
-
- Secondly, ISDN extends a common channel signaling system to the user.
- Unlike POTS where once the necessary number of digits had been sent
- to the switch, at which point the only signaling left was the switch-
- hook, the ISDN ccs is always alive and much more powerful. In the
- BRI, this signaling channel is 16 kbit/s wide, in the PRI it is 64
- kbit/s wide.
-
- A very simplified description to be sure, but think about the idea
- that now you will have a powerful (in terms of protocol) access to
- the intelligence available in the network. Almost anything you can
- think of is possible. Oh, BTW, in the BRI all this runs over a
- single copper pair, the PRI uses two pair or co-ax, depending on
- the carrier system.
-
- If I can answer any more questions, you can try e-mail to my site,
- or if it is of general interest, pop them up here.
-
- >--
- > / \
- >@###I===============> "Know me as GORD of GREYHAWK..." <===============I###@
-
- Bob [bob1@tango.cos.com]
-
- > \ /
- >rogue@ucrengr.ucr.edu UC Riverside -- home of the Guildsman
-