QoS Definition, Measures and Requirements
QoS is the ability of a network element (e.g., an application, host or router) to have some level of assurance that its traffic and service requirements can be satisfied
- enables a network to deliver a traffic flow end-to-end with the guaranteed maximum delay and guaranteed rate required by the user process (within agreed error boundaries)
Three levels of QoS measures
- Application QoS
- bandwidth control & traffic policing for individual traffic stream accessing servers
- Access QoS
- bandwidth control & traffic policing for individual traffic stream entering the Net
- Backbone/Core QoS
- network resource allocation & control on aggregate traffic
QoS requirements
- Traffic classification, Traffic shaping, Policing, Prioritization, Measurement, Provisioning, Service level management/monitoring