There's a protocol being worked on called STIR/SHAKEN to address robocalls [0]. It's more like website / browser certificate PKI than spam filtering. Some of th

There's a protocol being worked on called STIR/SHAKEN to address robocalls [0]. It's more like website / browser certificate PKI than spam filtering. Some of the major US telcos are working toward implementation already. [0] https://transnexus.com/whitepapers/understanding-stir-shaken/ https://transnexus.com/whitepapers/understanding-stir-shaken...