This paper highlights best practices in the application of the most popular communication protocols, such as IEC61850 and DNP3.0, with regards to the protection relay. It provides an overview of how SCADA and automation devices interact with protective relays from protection engineers' perspective. It also describes the different roles protection relays, RTUs and automation devices can play in SCADA and different architectures. Specific operational functionality such as SBO and control messages is detailed. This paper also compares the functionality and intent of the use of MMS messages in IEC 61850 as compared to GOOSE messages.