[LINK] Why don't telcos cut off bulk scam calls

[David]

On Sunday, 21 September 2025 08:36:32 AEST Tom Worthington wrote:

>> But how?  If all banks ...
> Not, banks, telcos. They could identify scammers, by flagging large numbers of very short calls coming from the same source.

Whoops, you're right, I happened to be thinking about banks at the time!
But it's also true that doing things on a bigger scale (telcos instead of banks) might be more difficult and less reliable.

>> ... configure a white-list of acceptable calling numbers ...
> Yes, I could configure a white list. But that doesn't help where the sender blocks their number or uses a large bank of numbers.

I think the idea is to white-list your _approved_ calling numbers and unconditionally reject everything else.  If an approved caller initiates calls from a PABX, these can be handled by using wild cards.

Of course the ATA normally connects to a router, and all VoIP calls from a given country can be blocked there before they even reach your ATA.

_DavidL_