Quality of Service
QoS Features and Components
Cisco 350, 350X and 550X Series Managed Switches, Firmware Release 2.4, ver 0.4
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QoS Features and Components
The QoS feature is used to optimize network performance.
QoS provides the following:
•
Classification of incoming traffic to traffic classes, based on attributes, including:
-
Device Configuration
-
Ingress interface
-
Packet content
-
Combination of these attributes
QoS includes the following:
•
Traffic Classification
—Classifies each incoming packet as belonging to a specific
traffic flow, based on the packet contents and/or the port. The classification is done by
ACL (Access Control List), and only traffic that meets the ACL criteria is subject to
CoS or QoS classification.
•
Assignment to Software Queues
—Assigns incoming packets to forwarding queues.
Packets are sent to a particular queue for handling as a function of the traffic class to
which they belong. See
•
Other Traffic Class-Handling Attribute
—Applies QoS mechanisms to various
classes, including bandwidth management.
QoS Operation
The type of header field to be trusted is entered in the
page. For every value of
that field, an egress queue is assigned, indicating through which queue the frame is sent, in the
page or the
page (depending on whether the trust
mode is CoS/802.1p or DSCP, respectively).
