AT INTERNET FIBER

Depends on which fiber tier subscribed to, but I would speculate that 80% of fiber customers subscribe to the lowest fiber speed tier of 300/300. Running the SHM app gateway to ATT server is likely seeing around 110% of speed tier, once leave the ATT network speeds can be influenced by many different factors and are not guaranteed. 

My 80% estimate is based upon company provided information that current monthly fiber average is around $67 for around 8.2 million fiber subscribers, and current retail fiber pricing by speed tier are $60, $70, $85, $155 and $255 before autopay/paperless billing discount leading to $55, $65, $80, $150 and $250 for 300, 500, 1000, 2000 and 5000 plans. 

https://www.att.com/internet/internet-service-plans/

... you posted this in the wireless forum. Wireless is cell phones not internet

Moving....