What is QOS in networking?

QoS(Quality Of service) in Networking:

In simple words, QoS is the ability of the network to provide better or special service to a set of users and application to the the detriment of others.

• “ability of the network”-it means that this will be done by network infrastructure i.e., switches and routers. There will be no traffic shaping server, the network infrastructure has to do this job.
• “to provide better or ‘special’ service”,- it means some traffic flow will be given preferential treatment and others will be given what is left over.
• “To a set of users and applications”, -it means which flow should get preference and which will get detriment treatment or less BW
• “To the detriment of others”-it means that since there will be a finite amount of bandwidth, if some flow is given more bandwidth there will be less available for the remaining traffic.
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