About Quality of Service (QOS)

Quality of Service is a collection of components that enable differentiation and preferential treatment for subsets of data transmitted over the network. QOS components constitute the Microsoft implementation of Quality of Service.

QOS technology has implications for both the application programmer and the network administrator. By writing QOS-enabled applications, programmers can:

• Specify or request bandwidth requirements particular to their application, such as latency requirements for streaming audio.
• Write mission-critical applications for a corporate environment that are guaranteed to get their required bandwidth — provided permissions and bandwidth availability exist.

Just as importantly, network administrators can leverage knowledge of Quality of Service to:

• Control network device resources based on user policy and/or application usage.
• Reserve portions of a given bandwidth, whether an Ethernet subnet or a WAN interface, for applications or users that require such availability for core business activities.
• Shape and smooth the traffic that clients submit to the network, thereby avoiding the overburdening of switches and routers suffered with traditional burst transmissions.

QOS achieves all this through programmatic interfaces, the cooperation of multiple components, and communication with network devices throughout the end-to-end network solution.