To enable the integration of smarter and more flexible assets, requiring real-time data exchange, a progressive implementation of last generation Information and Communication Technologies (ICT), capable of providing management capabilities over more complex networks, must be expected [1]. As the modern energy transition brings more dynamic challenges to which the Electrical Power and Energy System (EPES) stakeholders will need to attend, in a digital enabled ecosystem, it is reasonable to consider the smart grid as a necessary evolution, to handle new requirements, such as digital security, real-time interoperability and extended connectivity. This work presents a general overview of relevant cross-cutting issues and fundamental requirements to be considered, while tackling important digital and security challenges in the implementation of prominent smart grid use cases.