I would expect that a telecoms employee who was doing similar work on quality etc to be quite securely vetted.
If I was doing now what I did back in the day For BT / Dialcom (I had root on the UK's main ADMD) I would probably have to pass DV vetting (TS in USA terms)
What about all the telecom APIs like Twilio? They have raw access to millions of phone calls every day. I doubt they have ‘secure rooms’ for debugging.
If I was doing now what I did back in the day For BT / Dialcom (I had root on the UK's main ADMD) I would probably have to pass DV vetting (TS in USA terms)