QoS - Hierarchical QoS

HQoS, or Hierarchical Quality of Service refers to an advanced method of managing network traffic to ensure efficient utilization of resources and maintaining the QoS. In a typical QoS setup, traffic is managed based on defined policies to prioritize certain types of traffic over others. However, HQoS takes this a step further by allowing for multi-level (hierarchical) QoS policies.

This is sometimes referred to as the implementation of nested QoS policies.

HQoS is part of the wider Modular QoS CLI (MQC) feature set where MQC forms the foundation for implementing QoS policies like policing, shaping and prioritization, while HQoS extends the capabilities of MQC by allowing the introduction of hierarchy in those QoS policies i.e. the nesting of policies. This means you can have a QoS policy within another QoS policy, allowing for more complex and granular traffic management.

Here are the key features of HQoS:

  1. Layered Policy Structure: HQoS allows for the creation of a multi-tier policy structure. This means you can define QoS policies at different levels, such as per interface, per sub-interface, or even per traffic class within a tunnel.

  2. Enhanced Traffic Management: By using HQoS, network administrators can implement more granular control over traffic, ensuring that critical applications receive the necessary bandwidth and latency requirements, while less critical traffic is managed accordingly.

  3. Complex Traffic Shaping and Policing: HQoS enables more complex traffic shaping and policing mechanisms. This is especially useful in environments where bandwidth needs to be allocated and limited in a very precise manner.

  4. Improved Scalability: With HQoS, networks can handle a larger variety of traffic types and more complex network topologies, making it a good solution for large-scale or rapidly growing networks.

  5. Service Provider Applications: HQoS is particularly useful for service providers who need to manage different service levels for different customers or types of traffic.

HQoS provides a more sophisticated and layered approach to managing network traffic, ensuring optimal performance and adherence to specific QoS requirements for various types of network traffic.