HP VAN SDN Controller Administrator Guide v3

External applications can be developed in any language and are deployed on a platform outside
the controller platform or on the same platform as the controller. External applications interact with
the controller using the REST API services exported and advertised by the controller platform, and
by native applications deployed on the controller. Because external applications are deployed
outside the controller platform they cannot extend the REST API or GUI surface of the controller.
External applications are suitable for applications that have relatively infrequent and high latency
control interactions with network devices, and when deploying on a different platform is required.
1.1 Supported Switches and OpenFlow Compatibility
For information on supported network switches and OpenFlow versions, see the HP VAN SDN
Controller and Applications Support Matrix.
CAUTION: OpenFlow switches in a controller domain should not be connected in a loop topology
with switches outside the domain. Allowing such connections can create broadcast loops inside
the OpenFlow network. For more on packet-forwarding decisions, see “Hybrid mode for controlling
packet-forwarding” (page 75).
NOTE: Including a switch that does not support OpenFlow in a controller domain creates two
separate clusters.
1.1.1 OpenFlow requirements
The controller must be connected to a network that includes one or more switches configured to
run OpenFlow. HP recommends that you plan and implement the switch OpenFlow configurations
before connecting the controller to the network.
NOTE: Running the OpenFlow control mode on a specified switch VLAN disrupts the traffic on
that VLAN until the controller configures the required flow rules in the switch using the OpenFlow
controller API. For information on configuring OpenFlow, see the latest manual for the version of
OpenFlow running on your switches.
OpenFlow switches in the network must be configured to allow control by the HP VAN SDN
Controller. In a controller domain, including a switch that does not support OpenFlow or allow
control by the HP VAN SDN Controller creates separate clusters of OpenFlow networks.
1.1.2 IPv6 Traffic
IPv6 traffic running in the data plane of an OpenFlow network is supported when the controller is
operating with hybrid mode set to “true” (the default). In this state the controller is not aware of
the IPv6 traffic. However, with hybrid mode set to “false” (all packets sent to the controller), the
controller drops IPv6 packets, and they do not reach their destinations. For more information, refer
to the release notes.
8 Introduction