Applications operating over a best-effort network such as the Internet receive no QoS guarantees.
The QoS experienced by flows from any particular instance of an application can vary considerably. It is often possible for the construction of the flows to be adjusted, e.g. by changing the data rate, packet size, encoding, etc. For example, an audio tool might have the ability to use a variety of voice encoding schemes. However, making such adjustments typically requires a user with some expert knowledge to make static configuration changes to an application. A QoSReport is formed by summarising information gathered from raw QoS parameter measurements for the flow.