OpenFlow. It is a multivendor standard defined for implementing Software driven networking in networking equipment. The OpenFlow protocol defines the interface between an OpenFlow Controller and an OpenFlow switch, see Figure 1 below. The OpenFlow protocol allows the OpenFlow Controller to instruct the OpenFlow switch on how to handle incoming data packets.

Multicast: is similar to a broadcast in the sense that its target is a number of machines on a network, but not all. Where a broadcast is directed to all hosts on the network, a multicast is directed to a group of hosts. The hosts can choose whether they wish to participate in the multicast group (often done with the Internet Group Management Protocol), whereas in a broadcast, all hosts are part of the broadcast group whether they like it or not! Class D IP used for multicast since they are only used as destination addresses. Application needs to support multicast. When router receives multicast traffic it asks every host connected if they want multicast. If the host wants multicast it will use IGMP protocol to say so.