US Patent 9094227 Power management network system

A power management network system includes an advanced metering infrastructure (AMI) to communicate with a power supply source to receive power information and an energy management system (EMS) connectable to the AMI to control operations of home appliances on the basis of the power information. A first security table is in at least one of the AMI and the EMS, and the first security table has a security code to encode data with respect to the power information. A security reinforcement unit connectable to the AMI or the EMS includes a second security table to update the first security table.