https://docs.google.com/drawings/d/1fhrZgI_MEczqug9JHSa6UEfJHWKRp7k0A3NwlUUC4do/
https://www.128technology.com/wp-content/uploads/2019/10/white-paper_-quality-of-service.pdf
AT&T Service Classes
https://docs.128technology.com/docs/bcp_att_avpn_configuration/#att-service-classes
The 128T solution supports a 4 class model ( Traffic-class = High, Medium , Low and Best effort ) .
The 128T router uses four traffic engineering queues for prioritizing egress traffic during times of congestion or link contention.
