Caller ID (was Re: Enough!)
At 21:08 15/05/01 +0100, you wrote: They already offer it. You can bar up to ten numbers (IIRC). I don't know how it deals with withheld numbers. Never checked. I'm sure I remember reading somewhere that you always send your CID when you make a phone call. If you choose to withhold the ID, it still gets sent, it just gets sent with a 'do not disclose' flag set, which all (BT approved) phones and services (like 1471) must honour. Therefore it should be easy for BT themselves to offer something that can bar CID witheld calls. But this might be wrong, or might just be how the US system works or something. -- Jonathan Peterson Technical Manager, Unified Ltd, 020 7383 6092 [EMAIL PROTECTED]
Re: Caller ID (was Re: Enough!)
Jonathan Peterson [EMAIL PROTECTED] writes: I'm sure I remember reading somewhere that you always send your CID when you make a phone call. If you choose to withhold the ID, it still gets sent, it just gets sent with a 'do not disclose' flag set, which all (BT approved) phones and services (like 1471) must honour. Therefore it should be easy for BT themselves to offer something that can bar CID witheld calls. But this might be wrong, or might just be how the US system works or something. This is basically right but some ways of making a call don't send any CLI at all and the US and UK systems are different. The BT specs are online:- http://www1.btwebworld.com/sinet/227v3p1.pdf -- 1024/D9C69DF9 steve mynott [EMAIL PROTECTED] the difference between a moral man and a man of honor is that the latter regrets a discreditable act, even when it has worked and he has not been caught. -- henry l. mencken
Re: Caller ID (was Re: Enough!)
On Wed, May 16, 2001 at 10:59:07AM +0100, Robin Szemeti wrote: I do keep intending to do something cute with my ISDN adapter and log the stuff coming out of the D channel and see whats in there ... but time has prevented it etc. I'd be interested to hear how you get on... I was under the impression that the D channel was an always on 16k-thing. It'd be interesting to see what gets sent down there normally... -Dom
Re: Caller ID (was Re: Enough!)
On Wed, 16 May 2001, Dominic Mitchell wrote: On Wed, May 16, 2001 at 10:59:07AM +0100, Robin Szemeti wrote: I do keep intending to do something cute with my ISDN adapter and log the stuff coming out of the D channel and see whats in there ... but time has prevented it etc. I'd be interested to hear how you get on... I was under the impression that the D channel was an always on 16k-thing. It'd be interesting to see what gets sent down there normally... CLI / Destination number that kind of thing. Signalling information basically. MBM -- Matthew Byng-Maddick [EMAIL PROTECTED] +44 20 8980 5714 (Home) http://colondot.net/ +44 7956 613942 (Mobile) In California they don't throw their garbage away -- they make it into television shows. -- Woody Allen, Annie Hall
Re: Caller ID (was Re: Enough!)
On Wed, 16 May 2001, Dominic Mitchell wrote: On Wed, May 16, 2001 at 10:59:07AM +0100, Robin Szemeti wrote: I do keep intending to do something cute with my ISDN adapter and log the stuff coming out of the D channel and see whats in there ... but time has prevented it etc. I'd be interested to hear how you get on... I was under the impression that the D channel was an always on 16k-thing. It'd be interesting to see what gets sent down there normally... ummm it might be 9k6 but yes, its always on. My card will do either two B (64k) channels or a B and D channel ... most of what gets sent down there is CLID, charge info, etc .. I think they strip a load of it off if you only pay for home highway .. and allow it through if you pay for business highway... ie they actually go to some trouble to provide a worse service .. fules. -- Robin Szemeti Redpoint Consulting Limited Real Solutions For A Virtual World
Re: Caller ID (was Re: Enough!)
Matthew Byng-Maddick [EMAIL PROTECTED] writes: On Wed, 16 May 2001, Dominic Mitchell wrote: On Wed, May 16, 2001 at 10:59:07AM +0100, Robin Szemeti wrote: I do keep intending to do something cute with my ISDN adapter and log the stuff coming out of the D channel and see whats in there ... but time has prevented it etc. I'd be interested to hear how you get on... I was under the impression that the D channel was an always on 16k-thing. It'd be interesting to see what gets sent down there normally... CLI / Destination number that kind of thing. Signalling information basically. I have heard of people using the D channel signalling to communicate for free. -- 1024/D9C69DF9 steve mynott [EMAIL PROTECTED] liberty is always dangerous, but it is the safest thing we have. -- harry emerson fosdick
Re: Caller ID (was Re: Enough!)
Steve Mynott wrote: I have heard of people using the D channel signalling to communicate for free. I've also heard of phone companies cursing such users and trying to ban programs that support that. At least in Germany, there was a program (or several?) that took advantage of the fact that when you initiate a connection, you can also transfer a small data packet. So they would initiate a connection and include a small data packet, then immediately tear down the connection before it was answered, and initiate another connection with the next few bytes. All this stuff was free (since no connection was established completely), but apparently a lot of load on the switching network. However, German Telecom used to have a service (don't know whether they still do) whereby you could have an always-on connection using the D channel with a type of Datex-P-over-ISDN (a packet-switched(?) network in Germany where you pay by the packet rather than by the minute, and where no permanent connections are established: a bit like UDP). So you could have your email delivered to you, or stock ticks, or other stuff that didn't need high bandwidth. Cheers, Philip -- Philip Newton [EMAIL PROTECTED] All opinions are my own, not my employer's. If you're not part of the solution, you're part of the precipitate.
