The building block of today's world are not materials, but, computers and algorithms with communication networks between physical entities. A cyber physical system (CPS) is a system in which the cyber and physical entities of the system work together towards a common goal, for example a water treatment facility or an electricity distribution system. These cyber physical infrastructures affect day to day lives of people and hence become target point for the attackers to disrupt normal daily life. Owing to the complexity of a cyber physical system, the attacks have themselves become sophisticated and harder to detect. These sophisticated attacks no longer attempt to steal information, however, intend to corrupt it inside the system in order to affect the normal functioning of the system. In order to identify such attacks in a CPS, this thesis uses the multiple security domain non-deduciblity model. The MSDND model divides the system into security domains and reduces the notion of trust into the system by replacing it with invariant based valuation functions. This work concentrates on the Future Renewable Electric Energy Distribution Management System (FREEDM) as a smart grid infrastructure. This thesis will attempt to identify potential ways in which smart grid infrastructure FREEDM can be attacked and suggest measures to identify the attacker using the MSDND model. While doing so this thesis concentrates on building blocks of the FREEDM system i.e. the state collection protocol and its distributed nature.