Netgear XS728T – ProSAFE® 10 Gigabit Smart Managed Switch Guia Do Administrador

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Quality of Service
Use the features you access from the QoS tab to configure Quality of Service (QoS) settings on 
the switch. 
In a typical switch, each physical port consists of one or more queues for transmitting packets on 
the attached network. Multiple queues per port are often provided to give preference to certain 
packets over others based on user-defined criteria. When a packet is queued for transmission in 
a port, the rate at which it is serviced depends on how the queue is configured and possibly the 
amount of traffic present in the other queues of the port. If a delay is necessary, packets are held 
in the queue until the scheduler authorizes the queue for transmission. As queues become full, 
packets have no place to be held for transmission and get dropped by the switch.
QoS is a means of providing consistent, predictable data delivery by distinguishing between 
packets that have strict timing requirements from packets that are more tolerant of delay. 
Packets with strict timing requirements are given special treatment in a QoS-capable network. 
With this special treatment in mind, all elements of the network must be QoS capable. The 
presence of at least one node that is not QoS capable creates a deficiency in the network path, 
and the performance of the entire packet flow is compromised.
The QoS tab contains menus that provide access to the following sections: