David,

In answer to your queries:

1.
In Europe the UK has a Caller Display Service up and running. France are
scheduled to implement CLI in September 1997. Both UK and France use
protocols based on the Bellcore spec: GR - 30, (FSK modem) but with
differences in the method of alerting, timings and impedances.

Sweden, Denmark and Holland have implementations based on DTMF signalling.

2.

Both the UK and France specify AC impedances which can be found in the
following specs:

UK:
 BT network: SIN 242, Issue 2, November 1996 " Calling Line Identification,
Terminal equipment requirements, Part 1 Idle state, down stream signalling.
Part 2 Loop state signalling.
 Cable Communications Association network:  TW/P&E/312  Issue 3, August
1995. "Caller Display Services Specification"

The AC impedance is mandatory for the BT network and optional for the Cable
networks (AC impedance specification is different for the two networks as is
the method of alerting).

France:

France Telecom: B 14-10 W,  October 1995. " Interface de reception de
l'identite du demandeur et de la notification pour terminaux analogiques"



3.

Software requirements are based on the requirements of the Bellcore CLI
protocol:  GR - 30 "Voiceband Data Transmission Interface. Generic
Requirements".


There are a number of pan-European specifications in progress at ETSI
(European Telecommunications Standards Institute) of which two are scheduled
for publication this year:

ETS 300 659-1 "Public Switched telephone network (PSTN); Subscriber line
protocol over the local loop for display (and related) services; Part 1: On
hook data transmission"

ETS 300 778-1 "Public Switched telephone network (PSTN); Protocol over the
local loop for display services; Caller Display Service - Terminal Equipment
Requirements; Part 1: Off-line data transmission".


Hope this helps.


Best regards, 



...............................................
Bjorn Hansen 
Nortel Technology, London Road, Harlow,Essex,UK
[email protected], ESN 742-3265, 
Tlf: +44 1279 403265, Fax: +44 1279 451866
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