Introduction

As of the end of 2019, AT&T, Bandwidth, Charter, Comcast, Cox, T-Mobile, and Verizon announced that they had upgraded their networks to support STIR/SHAKEN. See Letter from Linda S. Vandeloop, Assistant Vice President, Regulatory Affairs, AT&T Services, Inc., to Marlene H. Dortch, Secretary, FCC, WC Docket No. 17-97, at 1 (filed Feb. 5, 2020) (AT&T ................
................