At 04:22 AM 6/6/01 -0500, Dee wrote the following:
>I live in a small city have been using a dial up provider for interenet
>connnection. We are now offered ISDN and DSL. I have no clue which one
>to get. Would this group be kind enough to tell me the differences and
>which one I should select?
ISDN -- Integrated Services Digital Network
===============================
There are two types of ISDN: Primary Rate Interface (PRI) and Basic Rate
Interface (BRI). PRI ISDN is generally found in telephone switches, computer
telephony, voice processing, and dial-up Internet access. Residential
installations and small businesses chiefly use BRI ISDN. A BRI ISDN link
divides the telephone line into 3 digital channels: 2 "B" channels and one
"D" channel, each of which can be used simultaneously. The "B" channels are
used to transmit data, at rates of 64k or 56k (depending on your telephone
company). The "D" channel is used for
signaling functions, such as call setup. You can use either or both "B"
channels for LAN-to-LAN access, Internet access, videoconferencing, or other
applications that demand higher bandwidth than analog modems can provide.
To achieve an aggregate 128-Kbps throughput, all newer ISDN modems support
the multi-link PPP channel-bonding technology, which lets two connecting
units negotiate and combine two or multiple channels to serve as one larger
pipe with expanded bandwidth.
ISDN services never did not take off as planned in the U.S. Users complained
that it was difficult to install, that the phone companies took forever to
set up the lines, that technical support was inefficient, and that it was
too expensive. Most ISDN is used in Europe and Japan and with US businesses
involved in videoconferencing.
ISDN will cost more than DSL because of the special ISDN modem, circuits
required. The phone companies charge more for per minute access and most ISP
have an additional charge.
DSL -- Digital Subscriber Line
======================
This technology uses ordinary copper telephone wire to transmit data at
broadband speeds of up to 1.5Mbps. This is the same wire that is already
installed in hundreds of millions of homes and businesses throughout the
world. DSL is an "always-on" service, meaning you don't need to dial-in
every time you want to connect to the internet.
The nice thing about DSL is that your existing phone line can be converted
to DSL and you will then have two functions on one line. The local phone
company installs a line splitter and separates the telephone from the DSL line.
DSL is asymmetric, that is, the speed in one direction (upload) is different
than the speed in the other direction (download). Normally these are set to
a maximum of 384Kbps up and 1.5Mbps down. Other options are available and
are determined by the ISP and/or local telephone company. In addition, DSL
is limited to about 18,000 feet from the local telephone central office (C.O.)
DSL has been growing by leaps and bounds and in the US has surpassed almost
all other forms of Internet access. Pricing for DSL is very reasonable.
--
Gerry Boyd
============= PCWorks Mailing List =================
Don't see your post? Check our posting guidelines &
make sure you've followed proper posting procedures,
http://pcworkers.com/rules.htm
Contact list owner <[EMAIL PROTECTED]>
Unsubscribing and other changes: http://pcworkers.com
=====================================================
