I. Introduction
The increase in fuel prices, energy crisis, greenhouse gases emission, the increase in penetration of the renewable energy resources, and the increasing demand of energy are some of the major issues behind the driving force of upgrading the traditional grid into the intelligent grid. The basic power system topology has remained the same for the past decades, [1] with its operation limited within these domains, generation, transmission, distribution and customer domain with the solid ICT infrastructure. The conventional grid cannot resolve the major issues mentioned above due to its characteristic features i.e., one-way flow of information and electricity, its requirement of manual monitoring and restoration, limited control and also provide few choices to customers. Smart Grid is an intelligent power network that combines various technologies in power, communication and control which can monitor and optimize the operations of all functional units from electricity generation to end-users (customers/consumers) [2]. The emerging of SG presents some key benefits including, two-way flow of information and electricity, distributed generation, self-monitoring and self-healing, pervasive control and intelligent sensors through the entire network. The utilization of two-way flow of information and electricity, allow the SG to create an automated and distributed advanced energy delivery network [3] whereas the introduction of distributed generation and pervasive control enable the efficient delivery and exchange of real-time data between the devices within the domains [4]. Hence, the design and implementation of an efficient, sustainable, flexible, complex and secure communication infrastructure is of great importance, for high penetration integration of distributed renewable energy (DER) resources i.e. photovoltaic (PV), wind systems, e.tc in the SG [5].