6.2.b [vi] HQoS, sub-rate ethernet link
The QoS Hierarchical Queuing Framework (HQF) feature enables you to manage quality of service (QoS) at three different levels–the physical interface level, the logical interface level, and the class level of scheduling for applying QoS queuing and shaping mechanisms by using the modular QoS command-line interface (MQC) to provide a granular and flexible overall QoS architecture.
You can apply class-based queuing to any traffic class in the parent or child level of a hierarchical policy and obtain service levels for different sessions or subscribers.
Adam, Paul (2014-07-12). All-in-One CCIE V5 Written Exam Guide (Kindle Locations 5735-5736). . Kindle Edition.