Quality Of Service (Qos); Chapter 16 Quality Of Service (Qos); Overview; What You Can Do In This Chapter - ZyXEL Communications P-870HN-5xb User Manual

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H A P T E R

16.1 Overview

Quality of Service (QoS) refers to both a network's ability to deliver data with
minimum delay, and the networking methods used to control the use of
bandwidth. Without QoS, all traffic data is 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 application such as video-on-
demand.
Configure QoS on the Device to group and prioritize application traffic and fine-
tune network performance. Setting up QoS involves these steps:
Configure classifiers to sort traffic into different flows.
1
Assign priority and define actions to be performed for a classified traffic flow.
2
The Device assigns each packet a priority and then queues the packet accordingly.
Packets assigned a high priority are processed more quickly than those with low
priority 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.
This chapter contains information about configuring QoS and editing classifiers.

16.1.1 What You Can Do in this Chapter

• The General screen lets you enable or disable QoS, set the bandwidth, and
allow the Device to automatically assign priority to upstream traffic according to
the IEEE 802.1p priority level, IP precedence or packet length
page 195).
• The Queue Setup screen lets you lets you configure QoS queue assignment
(Section 16.4 on page
• The Class Setup screen lets you add, edit or delete QoS classifiers
16.5 on page
P-870HN-5xb User's Guide

Quality of Service (QoS)

197).
200).
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(Section 16.3 on
(Section
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