Is STIR/SHAKEN exclusive to SIP? Are there any plans to implement something similar on legacy SS7/TDM networks?

1. General Battling Robocallers with STIR/SHAKEN
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Explained in the presentation, using trunk groups on TDM gateways to segregate calls of various attestation levels. Check out the video starting at the TDM explaination https://youtu.be/zHullJT-yRI?t=1212