4 ms·
I would, from personal experience, construct a quite different list. Some of mine would be: * Every other country's telephone numbering is like one's own. *
by JdeBP 8y ago
I would, from personal experience, construct a quite different list. Some of mine would be:
* Every other country's telephone numbering is like one's own.
* Every other country's telephone numbering is like that of EU countries, or like the NANP.
* The last 10 digits are the subscriber number.
* Geographic numbers are actually geographic.
* 123456789 is a perfectly fine number to use for test calls.
* STD is exactly like NPA-NXX.
* The leading 1- in NANP long distance form is the country code.
* There are only national and international forms nowadays.
* Users do not use E.164 themselves.
* Emergency numbers are easy to filter out, as it's only one number.
There are also falsehoods that people believe about telephones, which I would start with:
* When you hear the ringing tone, the other end is already ringing.
* Your ringing tone comes from the other end.
* Every network sends in-band call progress tones.
* It's perfectly fine to use fax over a G.729 'phone.
* DTMF is in-band and universally supported.
* DTMF is out of band and synchronous to media.
* There is only one way that callees reject calls, and it never involves being connected.
* TPC does not need to know the correct physical location of your non-mobile 'phone.
* TPC tracks mobile 'phones through "a GPS chip".
* Calls can only be traced whilst the caller is on the line.
* Caller-ID is unspoofable and works across networks and across countries.
* The callee can always clear calls.
* Only the caller can clear a call.
- pault 8y ago> Calls can only be traced whilst the caller is on the line. You just punched a hole in the plot of every procedural crime drama. :)
- jedimastert 8y agoYou can add "Calls take a non-trivial amount of time (i.e 60 seconds) to trace" to that list. It's immediate.
- ams6110 8y ago> * The callee can always clear calls In the 1980s at school, the phone system in the dorms was a private system (you could connect to the public system by dialing 9 first). In this system, a call was not terminated until the originating side disconnected. So a common prank was to call someone, then not hang up. Now their phone was unusable.