A method for operating a software defined network (SDN) includes creating, by a software defined network controller, packet template information including a packet template and fill-in instructions, wherein the packet template defines a fill-in-the-blank packet. The method also includes sending, from the software defined network controller to a switch via a control channel, the packet template information and receiving, by the switch from a requestor, an incoming packet. The method further includes triggering, by determining that the incoming packet matches the packet template, the switch to generate an output packet, wherein the output packet is generated by using the fill-in instructions to fill in the fill-in-the-blank packet defined by the packet template. In addition, the method includes sending, by the switch to the requestor, the output packet.