I think Catena is a great feature that make the Nexus Switches the best choice for data center among others vendors offering.that make the service chaining/Insertion much more easier.this is a great value added to the nexus switches. i have two Q regarding Catena . 1- what is the deference between Catena and ITD ? 2- it mentioned it can used for sending traffic flow for monitoring (i think for DPI , Packet Capture , IDS/IPS ).what is the deference with Nexus Data Broker ? Thanks