DASS, Q931, ISDN - What is the difference

[David W. Haggett]

We are just about to change our 33.6 modems for an ISDN terminal
adapter, it's primary purpose being to connect to Demon.

Our switchboard (Seimens Hicom 150E) will handle outgoing calls of any
flavour, but say to ask our cable company.

We are on Telewest cable, and I have been told that the existing set-up
is a 15 channel DASS. Telewest can "reconfigure" us to have Q931 which
is supposed to be Euro standard. Telewest say to ask a TA manufacturer.

USR say we would need specifically ISDN 2e to use either the Courier i
or the Sportster TA, and had never heard of DASS or Q931. They
therefore suggested we talk to the manufacturer of our PBX and our cable
company.

So - four questions

1 Does anyone know of a TA that can be plugged in to a DASS line to use
1 x 64k channel?

2 Is Q931 the same as ISDN 2e?

3 If we get "reconfigured" to Q931, will this enable us to use "any"
ISDN TA

4 Would we be better advised to pay for a BT ISDN 2e line in addition
to our existing set-up.

Many thanks for reading.
--
Best Regards

David W. Haggett Tel 0181 288 7119
Project Manager Fax 0181 288 0780
READ Process Engineering A/S (UK)

[Bob Geddes]

In article <6QAtnBAJ...@readprocess.co.uk>, David W. Haggett
<david....@readprocess.co.uk> writes

>We are just about to change our 33.6 modems for an ISDN terminal
>adapter, it's primary purpose being to connect to Demon.
>
>Our switchboard (Seimens Hicom 150E) will handle outgoing calls of any
>flavour, but say to ask our cable company.
>
>We are on Telewest cable, and I have been told that the existing set-up
>is a 15 channel DASS. Telewest can "reconfigure" us to have Q931 which
>is supposed to be Euro standard. Telewest say to ask a TA manufacturer.
>
>USR say we would need specifically ISDN 2e to use either the Courier i
>or the Sportster TA, and had never heard of DASS or Q931. They
>therefore suggested we talk to the manufacturer of our PBX and our cable
>company.
>

sounds like you have a 2mbps ISDN 30 link into your switchboard running
DASS 2 protocol. this can have typically 6->30 voice/data/64k channels,

sounds like telewest could change this protocol to Q931 of you wish.
Perhaps your Siemens could also change protocol but I dont see any need
for a change if its not broke dont fix it.

A TA typically uses an ISDN2/ISDN2e line which has 2 voice/data/64k
channels and a different physical presentation from ISDN30.

boxes which take in an ISDN30 line and pass out an ISDN2 line are
expensive, but perhaps your Siemens can do this and give you an S0/ISDN2
interface?

>So - four questions
>
>1 Does anyone know of a TA that can be plugged in to a DASS line to use
> 1 x 64k channel?
>

no such animal

>2 Is Q931 the same as ISDN 2e?
>

no

>3 If we get "reconfigured" to Q931, will this enable us to use "any"
> ISDN TA
>

no

>4 Would we be better advised to pay for a BT ISDN 2e line in addition
> to our existing set-up.
>

probably unless your existing seimens can give you the equivalent of an
isdn2 interface.

>Many thanks for reading.

--
Bob Geddes

[Simon Goodfellow]

David W. Haggett wrote:

> We are just about to change our 33.6 modems for an ISDN terminal
> adapter, it's primary purpose being to connect to Demon.
>
> Our switchboard (Seimens Hicom 150E) will handle outgoing calls of any
> flavour, but say to ask our cable company.
>
> We are on Telewest cable, and I have been told that the existing set-up
> is a 15 channel DASS. Telewest can "reconfigure" us to have Q931 which
> is supposed to be Euro standard. Telewest say to ask a TA manufacturer.
>
> USR say we would need specifically ISDN 2e to use either the Courier i
> or the Sportster TA, and had never heard of DASS or Q931. They
> therefore suggested we talk to the manufacturer of our PBX and our cable
> company.
>

> So - four questions
>
> 1 Does anyone know of a TA that can be plugged in to a DASS line to use
> 1 x 64k channel?
>

> 2 Is Q931 the same as ISDN 2e?
>

> 3 If we get "reconfigured" to Q931, will this enable us to use "any"
> ISDN TA
>

> 4 Would we be better advised to pay for a BT ISDN 2e line in addition
> to our existing set-up.
>

> Many thanks for reading.
> --

> Best Regards
>
>
> David W. Haggett Tel 0181 288 7119
> Project Manager Fax 0181 288 0780
> READ Process Engineering A/S (UK)

DASS and Q931 are both varieties of ISDN PRI (ISDN30). If you can't get
the Hicom to provide you with an ISDN2 connection (which it is capable of
doing either with a Basic Rate card in the system or if you use the
dedicated phones an adapter on one of these) then Telewest can provide
ISDN2 connections, in our case we have a Q931 on the telephone system then
a second fibre with just one ISDN2 multiplexed off (Telewest's
mulitplexer,we just pay for an ISDN2 line).

Simon

[Adrian Kennard]

David W. Haggett wrote:
>
>...

> So - four questions
>
> 1 Does anyone know of a TA that can be plugged in to a DASS line to use
> 1 x 64k channel?
>
> 2 Is Q931 the same as ISDN 2e?
>
> 3 If we get "reconfigured" to Q931, will this enable us to use "any"
> ISDN TA
>
> 4 Would we be better advised to pay for a BT ISDN 2e line in addition
> to our existing set-up.

1. look at our web pages... <-:

DASS2 is a primary rate circuit, and can be Q931. You cannot connect
any small ISDN TA in to ISDN30.

You could ...

1. Get an internal ISDN2 extension on your PABX - as the PABX
manufacturer for this. It does not affect the telco. You then
use a TA or router or card on that (lots on or web pages).

2. You could take the chance to upgrade your PABX to something
nice like the network alchemmy Argent Office which does ISDN30
and includes an ISDN router and 10baseT hub and firewall and
NAT, and computer telephony integration over your LAN, and
analogue ports which support caller display...

The latter option may not sound to good, but I dont know the
details of what system you have now, or how much they would
charge for the internal ISDN2 card. A new system may be
cheaper <-:

Anyway, if you get ISDN2 internally have a look around for
equipment - dont assume that the imodem is the only option.
It is possibly not the best choice.

--
_
(_) _| _ . _ _ Andrews & Arnold Ltd, Bracknell, Berks, RG42 1ZZ
( )(_|( |(_|| ) ISDN Equipment and advice http://aa.nu/

[Barry Schofield]

On Wed, 11 Mar 1998 12:51:32 +0000, Bob Geddes <bo...@bobg.demon.co.uk>
wrote:

>In article <6QAtnBAJ...@readprocess.co.uk>, David W. Haggett
><david....@readprocess.co.uk> writes

DWH>>We are just about to change our 33.6 modems for an ISDN terminal

>>adapter, it's primary purpose being to connect to Demon.
>>

DWH>>Our switchboard (Seimens Hicom 150E) will handle outgoing calls

of any flavour, but say to ask our cable company.
>>

DWH>>We are on Telewest cable, and I have been told that the existing

set-up is a 15 channel DASS. Telewest can "reconfigure" us to have
Q931 which is supposed to be Euro standard. Telewest say to ask a TA
manufacturer.

I presume you are in Croydon the only area Telewest have Q.931 on a
Nortel switch. There should be no problem with our equipment, as
Telewest is trialing it in this area.

>>
DWH>>USR say we would need specifically ISDN 2e to use either the

Courier i or the Sportster TA, and had never heard of DASS or Q931.
They therefore suggested we talk to the manufacturer of our PBX and
our cable company.

This is completely wrong. Q.931 is used in the US and these are US
TA's. They do work with ISDN 2 which is based on the CCITT Q.931 and
cannot see why they should require ISDN2e which is a more up to date
version of the Q.931.

>>
BG>sounds like you have a 2mbps ISDN 30 link into your switchboard

running DASS 2 protocol. this can have typically 6->30 voice/data/64k
channels,

This is not relevent, DASS 2 is a signaling system behind the ISDN 2,
it is the reason for being unable to have Q.931 or ISDN 2e, ETSI
(super Euro-ISDN.)

>
BG>sounds like telewest could change this protocol to Q931 of you

wish. Perhaps your Siemens could also change protocol but I dont see
any need for a change if its not broke dont fix it.

No it requires a change of switch. Telewest have only one switch in
Croydon (DNS 100 from Nortel) under trial, and they eventually will
change their DASS 2 (GPT) switches to Nortel Q.931 switches, but do
not hold your breath.

>
BG>A TA typically uses an ISDN2/ISDN2e line which has 2 voice/data/64k

channels and a different physical presentation from ISDN30.

He has not mentioned primary rate ISDN and he does not have it anyway.

>
BG>boxes which take in an ISDN30 line and pass out an ISDN2 line are

>expensive, but perhaps your Siemens can do this and give you an S0/ISDN2
>interface?

He does not have primary, does he?

>
DWH>>So - four questions
>>
DWH>>1 Does anyone know of a TA that can be plugged in to a DASS line

to use 1 x 64k channel?
>>

BG>no such animal
>
DWH>>2 Is Q931 the same as ISDN 2e?
>>
BG>no

No that is misleading for his purposes the original specification
Q.931 (which is the original CCITT specification for ISDN on which all
others are based) is sufficient and he does not need ISDN 2e which is
a much higher standard.

>
DWH>>3 If we get "reconfigured" to Q931, will this enable us to use
"any" ISDN TA
>>
>no

Yes, you are right but most TA's will work on Q.931, ours do and can
see them working in Croydon. That is one of the advantages of Super
Euro-ISDN capability they are downwards compatible.

>
DWH>>4 Would we be better advised to pay for a BT ISDN 2e line in

addition to our existing set-up.

No you certainly would not, just look at the proce differences on our
web pages, count yourself lucky.

>>
BG>probably unless your existing seimens can give you the equivalent
of an isdn2 interface.

No this is not possible. if it were possible Siemens would have had a
field day many years ago.

>
DWH>>Many thanks for reading.

May we wish you every success, with Telewest, wish we had them near
us.

Barry Schofield

See our NEW POTS in a box. If your paying to much
to connect then look at see our NEW LCR routers.
see Lion's web site at www.lioncom.net.

[Adrian Kennard]

Barry Schofield wrote:
>
>....

> DWH>>4 Would we be better advised to pay for a BT ISDN 2e line in
> addition to our existing set-up.
>
> No you certainly would not, just look at the proce differences on our
> web pages, count yourself lucky.

Ah. Barry, you are a goldfish with the corresponding memory span...

You were the one, just a few days ago, insisting not only that ISDN2e
is so much better, but that an upgarde to 2e was free and a good idea.

This is a complete u-turn in recommendation and reasoning - just
goes to show.