3 ms·
AT&T shut down their GSM 2G network in 2017 - the remaining circuit switched calls were going out over UMTS (3G) until the shutdown.
by username190 4y ago
AT&T shut down their GSM 2G network in 2017 - the remaining circuit switched calls were going out over UMTS (3G) until the shutdown.
- p_l 4y agoThe radio interface used is 3G/4G, but it still used circuit switching instead of IMS (which uses GPRS channel - just like your 3G/4G/5G data - and SIP, iirc)