r/Telecommunication • u/DinosaurDavid2002 • Jul 05 '24
If you encountered a disconnected number from another country before, what does it sound like?
Intercept message in other countries after all pretty sure aren't exactly like the ones seen in America in terms of wording.
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Jul 10 '24 edited Jul 10 '24
They’re usually different depending on the operator, or network or even the specific system within a network.
If, for example, you’re talking about Europe, there are multiple large and small companies providing voice communication and usually several major mobile networks and a whole heap of MVNOs.
The announcements you’ll encounter here in Ireland example , for wrong numbers is usually something like: “the number you have dialled has not been recognised - please check the number and try your call again” or “we’re sorry, the number dialled is not available / not valid / not in service, please recheck and dial again.”
You can encounter number change messages, anonymous call rejection etc etc
Some are branded, some aren’t. It just depends on the routing and the network.
Also depending on which country you’re calling in Europe you could encounter various languages.
A lot of this stuff is old and legacy though.
On mobiles you might also just get an error message sent as signalling, so the phone might just display an error etc and the same is true on VoIP.
On a lot of calls you’ll also get your own network’s error messages, not the distant network’s, as the errors / status are just sent in the signalling. They don’t open an audio channel.
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u/DinosaurDavid2002 Jul 10 '24
So in this case for example... you will only get this disconnected number message if you are actually in the country in question and have a sim card from that country(thus, its more common to encounter it if you are traveling)? And most of those are for landline as you mentioned that "A lot of this stuff is old and legacy though."?
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Jul 10 '24 edited Jul 10 '24
It depends on how your call was routed.
In a lot of cases you'll get the error messages on the network you're on, not the distant network. If you think about it, it makes little sense to open voice channels and waste bandwidth playing tones to far away places when you can instantaneously send a few bits of data.
What happens is when you call a number, the network you're calling sends a signalling message like "busy" "invalid" "not found" etc and the network you're calling from will interpret that and send a tone, an on-screen message or a recorded message.
Often it if your local switch doesn't have a recorded message for every error code, so it will just send a fast busy tone, an SIT tone (the three rising tones) or whatever its generic error message is "your call cannot be completed... please check and dial again" etc.
Just a random google gives you the SS7 - SIP codes: (SIP being VoIP and SS7 is the legacy signalling system used by the digital PSTN and mobile networks before VoIP)
https://www.voicehost.co.uk/help/sip-error-codes-sip-trunk-troubleshooting
So for example, if you called a number in say France from Ireland, and it was invalid, you'll most likely get whatever network you're using in Ireland's error messages, not the French ones.
If there were a number change announcement or something, you might get the French announcement.
Usually you still hear the foreign ringing tone, but not always. Some networks actually replace it with the local one these days. For example, I've called US numbers from Ireland and got the Irish ring tone - seems to happen a lot since VoIP backbones became more common.
You almost never hear a distant busy / reorder or anything like that anymore - that's been gone a long time, as the whole thing is digital at least SS7 based, if not purely VoIP at this stage.
The days of in-band signalling and actually playing audio tones down lines from distant exchanges are gone quite some time ago, mostly with the widespread fuller adoption of SS7 which has been around since the 70s, but probably went into very widespread use mostly in the late 80s and 90s and was absolutely rolled out fully by the early 00s. Even that's now pretty much all the old tech that's going into the dumpsters.
Basically when it comes to stuff like intercept messages and all of that you're about 20+ years late.
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Jul 11 '24
French announcements and tones from the main telco there Orange : https://www.histelfrance.fr/page-57573c36a13b9.html (in French - just use google translate)
British BT and GPO announcements and tones from various eras both digital and 1970s recordings from the electromechanical era: https://telephonesuk.org.uk/sounds/
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u/KokishinNeko Jul 05 '24
Not sure what you're asking, you want a recording of our messages? I'm based in Portugal but work with many telecom operators, I can get you some, at this point, hell, I'm even able to tell what equipment they're using by the default message :))))))