Quality of Service | Glossary

Definition: 

Quality of Service is of particular concern for the continuous transmission of high-bandwidth video and multimedia information. This technologies provides differentiated handling and capacity allocation to specific flows in network traffic. This enables the network administrator to assign the order in which packets are handled, and the amount of bandwidth afforded to that application or traffic flow.

Further Reading: 

Book: End-to-end Qos Network Design  Book by Christina Hattingh and Tim Szigeti