Communication networks
Synchronization
Tags (data processing)
Rotary switches
Labels
Open systems interconnection
Data transfer
Switches
Transport layer (OSI)
Addresses (data processing)
Data layout
Industrial
Time
Network layer (OSI)
Packets (data transmission)
Information exchange
Digital signals
Data link layer (OSI)
Process control
Control systems
Indicator lights
Physical layer (OSI)
Control panels
Flashing lights