[Asterisk-Users] European Caller ID

[Nicolas Bougues]

On Sun, Mar 14, 2004 at 11:45:38AM +0100, randulo wrote:
> 
> Here in France, we currently do not have it enabled on any of out lines, 
> but I would consider paying for it if I thought * via X100p cards would 
> be able to detect it properly.
> 

Can't say, I have no such board.

> I know for example that when people are calling us from the US or from 
> London CID is not captured by France Télécom, because we have a free 
> service here where you can call a number to see if you missed any calls.
> 

FT does forward caller id when it has a chance to. But foreign
carriers may use strange "path" in call routing, and may not be able
to be able to send proper caller id.

Basically, you will only see it if the foreign caller has direct SS7
connectivity. Otherwise, the foreign carrier is probably forwarding
the call via some PRI, and often can't hide himself without hiding
the original caller as well.

> Are the technical "specs" of CID different all over? Comments, 
> experiences please?

CID, at least in France, exists in two flavours :
- carrier guaranteed, called NDI in France
- user provided (and thus, not guaranteed by the carrier), called NDS
  in France

On ISDN, the (french) carrier will usually provide both (out of which
Asterisk will usually use the NDI). On POTS, France Telecom will
usually forward the NDS if it looks correct (9 digits without leading
0), the NDI otherwise.

International CID is usually carried in E.164 format (and may, or not,
be dialable, depending on your local private exchange configuration).

-- 
Nicolas Bougues
Axialys Interactive