Allied Telesis AT-S63 - Manual (Page 258)

Chapter 13: Classifiers
258 Section II: Advanced Operations
Classifier
Guidelines
Follow these guidelines when creating a classifier:
ˆ Each classifier represents a separate traffic flow.
ˆ The variables within a classifier are linked by AND. The more variables
specified within a classifier, the more specific it becomes in terms of
the flow you are defining. For instance, specifying both a source IP
address and a TCP destination port within the same classifier defines
a traffic flow that relates to IP packets containing both the designated
source IP address and TCP destination port. However, there are some
restrictions to which variables can be used together in the same
classifier. For the restrictions, refer to “Classifier Criteria” on page 253.
ˆ The same classifier can be used for both an ACL and a QoS policy.
ˆ You can apply the same classifier to more than one ACL or QoS policy.
ˆ A classifier without any defined variables filters all packets.
ˆ You cannot create two classifiers that have the same settings. There
can be only one classifier for any given type of traffic flow.
ˆ The switch can store up to 256 classifiers.
ˆ You cannot modify a classifier if it belongs to an ACL or QoS policy
that has already been assigned to a port. You must first remove the
port assignments from the ACL or policy and reassign them after you
have modified the classifier.