Quality Of Service; Understanding Qos - Planet GS-5220 Series User Manual

4.9 Quality of Service

4.9.1 Understanding QoS
Quality of Service (QoS) is an advanced traffic prioritization feature that allows you to establish control over
network traffic. QoS enables you to assign various grades of network service to different types of traffic, such as
multi-media, video, protocol-specific, time critical, and file-backup traffic.
QoS reduces bandwidth limitations, delay, loss, and jitter. It also provides increased reliability for delivery of your
data and allows you to prioritize certain applications across your network. You can define exactly how you want
the switch to treat selected applications and types of traffic. You can use QoS on your system to:
• Control a wide variety of network traffic by:
• Classifying traffic based on packet attributes.
• Assigning priorities to traffic (for example, to set higher priorities to time-critical or business-critical
applications).
• Applying security policy through traffic filtering.
• Provide predictable throughput for multimedia applications such as video conferencing or voice over IP
by minimizing delay and jitter.
• Improve performance for specific types of traffic and preserve performance as the amount of traffic
grows.
• Reduce the need to constantly add bandwidth to the network.
• Manage network congestion.
QoS Terminology
• Classifier－classifies the traffic on the network. Traffic classifications are determined by protocol,
application, source, destination, and so on. You can create and modify classifications. The Switch then
groups classified traffic in order to schedule them with the appropriate service level.
• DiffServ Code Point (DSCP) － is the traffic prioritization bits within an IP header that are encoded by
certain applications and/or devices to indicate the level of service required by the packet across a
network.
User's Manual of GS-5220 LCD Series
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