[miki123211]

> Step zero is actually having a process/protocol where any phone is tamper evident meaning we can tell 100% that this call came from this operator and the operator knows the call came from this user.

This basically doesn't work because the mapping between phone numbers, users and operators isn't exactly 1:1:1.

Some businesses have a single number that they use as Caller ID on all their calls , despite having one corporate HQ in New York, one branch in New Orleans and one customer support callcenter in New Delhi. All of these use different carriers and are based in different countries, yet they're all legally authorized to use that number.

If you want to read more about why this is such a hard problem to solve, see https://computer.rip/2023-08-07-STIRred-AND-SHAKEN.html

[SoftTalker]

> ...yet they're all legally authorized to use that number.

But why? I get that they want a unifed appearance, but as a phone subscriber I want to know if it's BigCo calling from New Delhi vs. BigCo calling from Chicago.

[collinmanderson]

Amazing article about why phone spam is so much harder to fight than email spam.

Thank you for sharing it!

Now I need to lean SS7 signaling.