Figure 6.   A non-Niagara network (SnmpNetwork, in this example) in the Drivers container

A driver network is a top-level component in a station. For drivers that use field bus communications, such as Lonworks, BACnet, Snmp and Modbus (among many others), this component corresponds directly to a physical network of devices. Except for BACnet, the network component matches one-to-one with a specific comm port on the host platform. This port could be a serial port (RS-232 or RS-485), Lonworks FTT-10 port, or an Ethernet port.

A BACnet network component is unique because it supports multiple logical BACnet networks, which may use different comm ports. For example, if a host uses BACnet MS/TP, it may have one or more RS-485 ports.

Other non-field-bus drivers also correspond directly to the physical network of devices. For example, the Ndio (Niagara Direct Input/Output) and the Nrio (Niagara Remote Input/Output) drivers correspond to physical I/O points on a host controller or hardware I/O module (either directly attached or remotely connected).