Any ideas on how this will be implemented? I use voip.ms and I can put in my cell phone number as my caller ID so I don't need to pay for a DID (basically, rent a phone number) and calls come back to my cell.

I've thought about some potential SaaS products that would leverage a similar approach. But I would authenticate the number back to the customer before allowing it to be used to avoid spam/malicious use.

Based on this:

https://www.zdnet.com/article/at-t-comcast-successfully-test...

I'm guessing this is down a layer at the provider level. So in my case, voip.ms would verify the number I'm using as my caller ID is actually a number that comes back to me. Right now, I just tested by swapping my wife's cell number in, they do not validate this. Now I understand how people are spoofing numbers so easily.

Obvious approach is to voice call or text the number and require the confirmation code to be entered on the website. Just curious though if there are other requirements or if this is up to the provider.