priority, the application sets the logical priority as assigned by the flow class, and a cookie
that is derived from the base cookie of the OpenFlow class.
4.
Before sending the flow table modification message to the switch, the controller evaluates
the requested flow modification against the registered OpenFlow classes and replaces the
logical priority provided by the application with an actual priority.
In addition to enabling the controller to manage priorities for multiple applications, OpenFlow
classes enable the controller to validate flow modifications an application makes against a set
of expected flow modification requests. This capability means that the behavior of an application
must match the intent that the application disclosed when it registered with the controller:
•
The flow match must contain exactly the fields and field types that were disclosed when the
application registered with the controller. The controller validates field types but not field
value.
•
The action or instruction must fall into the category that was disclosed during registration.
An action is classified into one of the following categories:
FORWARD
DROP
PROCESS
STEAL
COPY
•
The upper 16 bits of the flow modification cookie must match the upper 16 bits of the base
cookie that was issued during registration.
OpenFlow Classes screen details
The OpenFlow Classes screen displays the OpenFlow classes that are currently registered with
the controller.
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Using the SDN controller UI