User Manual

Class
You can classify incoming packets at Layers 2, 3 and 4 by inspecting the following
information for a packet:
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Source/destination MAC address
•
EtherType
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Class of Service (802.1p priority) value (first/only VLAN tag)
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VLAN ID range (first/only VLAN tag)
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Secondary 802.1p priority value (second/inner VLAN tag)
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Secondary VLAN ID range (second/inner VLAN tag)
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IP Service Type octet (also known as: ToS bits, Precedence value, DSCP value)
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Layer 4 protocol (TCP, UDP and so on)
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Layer 4 source/destination ports
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Source/destination IP address
From a DiffServ point of view, there are two types of classes:
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DiffServ traffic classes
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DiffServ service levels/forwarding classes
DiffServ traffic classes
With DiffServ, you define which traffic classes to track on an ingress interface. You can
define simple BA classifiers (DSCP) and a wide variety of multi-field (MF) classifiers:
•
Layer 2; Layers 3, 4 (IP only)
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Protocol-based
•
Address-based
You can combine these classifiers with logical AND or OR operations to build complex
MF-classifiers (by specifying a class type of all or any, respectively). That is, within a
single class, multiple match criteria are grouped together as an AND expression or a
sequential OR expression, depending on the defined class type. Only classes of the
same type can be nested; class nesting does not allow for the negation (exclude option)
of the referenced class.
To configure DiffServ, you must define service levels, namely the forwarding classes/PHBs
identified by a DSCP value, on the egress interface. You define these service levels by
configuring BA classes for each.
Main User Manual772Configuration Examples
AV Line of Fully Managed Switches M4250 Series Main User Manual