PLANET WGS3-24240 - Manual (Page 201)

User’s Manual of WGS3-24000 / WGS3-24240
201
4.5 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:
• 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.
The QoS page of the WGS3 Layer 3 Switch contains three types of QoS - the Access Control List mode, Differentiated
Services mode or Class of Service mode can be selected. Both the three mode rely on predefined fields within the packet to
determine the output queue.
„ Access Control List
„ Differentiated Services
„ Class of Service
z 802.1p Tag Priority Mode –The output queue assignment is determined by the IEEE 802.1p VLAN priority tag.
z IP DSCP Mode - The output queue assignment is determined by the TOS or DSCP field in the IP packets.
z Port-Base Priority Mode – Any packet received from the specify high priority port will treated as a high priority
packet.
4.5.1 IP Access Control List
An ACL consists of a set of rules which are matched sequentially against a packet. When a packet meets the match criteria of a
rule, the specified rule action (Permit/Deny) is taken and the additional rules are not checked for a match. On this menu the
interfaces to which an ACL applies must be specified, as well as whether it applies to inbound or outbound traffic. Rules for the
ACL are specified/created using the ACL Rule Configuration menu.