ISDN

Is ISDN still being sold? Why does it work out more expensive than ADSL?

On Sun, 11 Sep 2005 15:09:34 +0100, "BDA" <(E-Mail Removed)> scrawled:

>Is ISDN still being sold? Why does it work out more expensive than ADSL?
>
Because ISDN is entirely different from ADSL. ISDN isn't just for
internet access. The fact that it is quicker than dial-up internet
access is a extra feature of its primary use which is generally voice
lines on commercially installed telephone systems. I've
fitted\utilised hundreds of ISDN lines and only ever used 2 of them
for internet access.
--
Stuart @ SJW Electrical

Please Reply to group

On Sun, 11 Sep 2005 15:09:34 +0100, "BDA" <(E-Mail Removed)> wrote:

>Is ISDN still being sold? Why does it work out more expensive than ADSL?

yes. Its a switched circuit system using a different exchange line
card to provide a dedicated 2*64k channel. ADSL is a contended shared
medium service.

Providing & changing the line card will be part of the cost story,
rather than routing your line via one port of a multiport DSLAM.

Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali

AOL - the unlimited ISP of choice for heavy downloaders.

On 11 Sep 2005 15:09, "BDA" <(E-Mail Removed)> wrote:

> Is ISDN still being sold?

Yes, unless you want to have the (previously popular) "Home Highway" (which
offers most feaures that Business Highway offers, ie 64k data, and analogue
all from one box, compared with ISDN 2e, where you need extra kit to enable
plain analogue equipment to be plugged in. <http://www.mckerracher.org/>

> Why does it work out more expensive than ADSL?

Lower demand, for one thing, historic pricing, for another, and that while
most ISPs might have some internal contention, the 64k path from customer
to ISP (or 128k, or 64/128k voice from user to user, if used for radio OB)
is guaranteed, while ADSL is a contended service and subject to much lower
speeds if the exchange is heavily used, unles customer is paying extra for
a 1:1 service. Peter M.


--
|
| UK ADSL <http://tinyurl.com/5jpa4> - Happy to save cash with Plus.Net!!
|

Also, ISDN2 enables a single copper pair to support 2 virtual lines.
So you can use ISDN2 to support 2 simultaneous 2-way calls, where as
ADSL supports only one.

I would hazard a guess also that the silicon used in analogue exchange
line cards is getting expensive as the vendors migrate their
manufacturing to ADSL muxes.

Nick

On 14 Sep 2005 02:43:38 -0700, (E-Mail Removed) scrawled:

>Also, ISDN2 enables a single copper pair to support 2 virtual lines.
>So you can use ISDN2 to support 2 simultaneous 2-way calls, where as
>ADSL supports only one.
>
Erm....? ADSL doesn't support calls as such, but you can have many
many more than 2 simultaneous calls on ADSL (100's IIRC).

However, the voice side of and ADSL line will only support one call.
--
Stuart @ SJW Electrical

Please Reply to group

My apologies. The point I sought to make was that ISDN2 is capable of
providing the same functionality as 2 separate copper pairs, which for
most users is the ability to support a full-duplex call on each copper
pair. This would be consistent with pricing ISDN2 at a similar level
to 2-off analogue lines, so answering the OP's question in part.
Indeed, Pair Gain could have been a good application for ISDN2, but BT
stayed with DACS (BT engineers may have something to say about the joys
of installing telephony equipment running at 120v). With regard to
ADSL, owing to the way in which frequency spectrum is used, a copper
pair on which ADSL is provided is capable only of supporting one
full-duplex call. I concur that you can do what you like with VoIP
calls over the higher frequencies, depending on what your customers are
prepared to put up with in terms of QoS.

Nick