ZyXEL Communications P-660HN-F1A, User Manual

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P-660HN-F1A User’s Guide
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Quality of Service (QoS)
16.1 Overview
Use the QoS screens to set up your P-660HN-F1A to use QoS for traffic
management.
Quality of Service (QoS) refers to both a network’s ability to deliver data with
minimum delay, and the networking methods used to control bandwidth. QoS
allows the P-660HN-F1A to group and prioritize application traffic and fine-tune
network performance.
Without QoS, all traffic data are equally likely to be dropped when the network is
congested. This can cause a reduction in network performance and make the
network inadequate for time-critical applications such as video-on-demand.
The P-660HN-F1A assigns each packet a priority and then queues the packet
accordingly. Packets assigned with a high priority are processed more quickly than
those with low priorities if there is congestion, allowing time-sensitive applications
to flow more smoothly. Time-sensitive applications include both those that require
a low level of latency (delay) and a low level of jitter (variations in delay) such as
Voice over IP (VoIP) or Internet gaming, and those for which jitter alone is a
problem such as Internet radio or streaming video.