US Patent 7289994 Interconnected zones within a process control system

A process control system includes multiple zones containing process control network communicatively interconnected to exchange information necessary to monitor the system and to perform process control. Each zone may include an inter-zone server that controls the exchange of information between the zones via communication links. In addition to controlling the routing of information between the zones, the inter-zone servers may perform additional processing on the information being exchanged, such as security monitoring, language translation and version control.