This paper firstly introduces the concepts of Software Defined Networking (SDN), Network Function Virtualization (NFV), and Cloud Computing Technologies with their interdependencies and then focuses on the SDN based technology named “Service Chaining.” Service Chaining applications provide a means to dimension and utilize services such as Firewall, Deep Packet Inspection (DPI) and Intrusion Detection System (IDS) in the most efficient manner, attempting to only carry the flows that only require a particular service to that particular service box. Efficient service chaining requires some topics to be investigated such as relation between Network/Cloud Management System and service chaining application, task distribution among NFV and SDN Controller and the case when a particular service can be provided over the cloud in a Network as a Service model (NaaS). Second half of the paper is dedicated to describing these problems which are open research areas.