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seCurity and PrivaCy in smart Grids
will be specific to the power domain, other supporting services such
as Web servers, authentication services (Lightweight Directory Access
Protocol (LDAP), Active Directory) and databases may be used.
Specific systems within this environment include
• SCADA/ EMS (energy management system) servers: Control
servers that perform monitoring, control, and state estima-
tion tasks
• Historians: Databases that maintain historic control system
data for trending analysis
• Human-machine interfaces (HMIs): Systems that provide
operator interfaces to the SCADA/ EMS systems
Often, control systems maintain some connectivity to other corpo-
rate local-area networks (LANs) or other third parties due to require-
ments to collec ...