Land line down but internet still working?

[SteveC]

It appears that all of the telephone land lines in the village are not working, but our broadband internet is still functioning fine.
It hasn't failed over to the mobiles.

Any ideas?

[Kim]

Is failing over to mobiles a thing?

No doubt our-favourite-telco are working to fix it.

[SteveC]

TBH I don't know. The failover works the other way. If the phones cannot find a decent signal, but can find wifi all the calls, in and outbound, get routed that way.
That, of course, is rather easier to implement.

[Feanor]

Assuming ADSL / VDSL...

If it's affecting all landlines in an area, then the fault is not on any of the individual lines back to the exchange / street cabinet..
Once the line reaches the exchange (or street cabinet), then it basically splits: the Broadband goes to one set of equipment, and the voice calls to another.

So it's perfectly possible for the broadband stuff to remain working where the voice-call gubbinses has fallen over.

(Also, for a single line, ADSL / VDSL can continue to function even in the face of line faults which kill voice calls.)

[Kim]

TBH I don't know. The failover works the other way. If the phones cannot find a decent signal, but can find wifi all the calls, in and outbound, get routed that way.
That, of course, is rather easier to implement.

Oh, that's a completely different badger.

I mean, there's no reason your voice provider couldn't route calls to another number^[1] during an outage (at least one sufficiently far downstream that the call-routing stuff still works), but it's the sort of thing you'd have to explicitly set up.  It's not something Openreach would be able to do unilaterally in response to an exchange fault, because people will have different voice providers with their own upstream systems.


_{[1] VOIP from the Reassuringly Expensive Packet-Pushing Company of Bracknell, GREAT BRITAIN, can be configured to route calls to arbitrary PSTN numbers instead of (or in addition to) your SIP phone or server, which is handy.}

[Kim]

So it's perfectly possible for the broadband stuff to remain working where the voice-call gubbinses has fallen over.

And if it's a single line, it's possible for the DSL signal to jump a physical gap that would appear as a break in the circuit at voice frequencies.  RF can be sneaky and confusing like that.

[Feanor]

Yes, I added that line as you were typing that...

[SteveC]

If it's affecting all landlines in an area, then the fault is not on any of the individual lines back to the exchange / street cabinet..
Once the line reaches the exchange (or street cabinet), then it basically splits: the Broadband goes to one set of equipment, and the voice calls to another.

I suspect this is the issue. It's pretty well the whole village as far as we can tell. There was a chap in hi-viz with his head in one of the street cabinets when we came home.