Quality of service
Also known as QoS
Prioritizing certain network traffic so that latency-sensitive applications stay usable under load.
Voice and video degrade immediately when packets are delayed or dropped, while a file transfer does not care. QoS marks and queues traffic so the sensitive traffic goes first.
It only helps at points of congestion, which is usually the internet uplink. Applying it across an underused internal network achieves nothing.
Where this comes up
Quality of service sits inside our networks and infrastructure work. If you are trying to work out what this means for your own environment rather than in the abstract, that is the page worth reading next, and a short call will get you a straight answer faster than either.
Related terms
Latency The delay between sending data and it arriving, usually measured as a round trip in milliseconds. Packet loss Data that never arrives at its destination and has to be retransmitted, or is simply lost. Teams Phone Microsoft's calling capability that turns Teams into a business phone system with real phone numbers. SD-WAN Software-defined wide area networking, which manages multiple internet links intelligently across sites.