BLUETOOTH: An open wireless standard for short-distance communication. Bluetooth provides a wireless interface to replace cable connections between devices.

BRIDGE: A device for connecting two separate networks.

ETHERNET: Network standard developed by Intel, DEC, and Xerox, which has been widely used since 1976.

FIBER OPTIC: A transmission medium with an inner conductor made from glass or plastic and several coatings as protection against mechanical strain.

FIELDBUS: A fieldbus or bus is an industrial communication system that connects different devices, sensors, actuators, and drives to a controller.

FREQUENCY: The key identifier for a radio, which defines whether the system is license-free or requires a license from a local regulatory body, such as the FCC.

FRESNEL ZONE: The area around the direct line connecting the transmitting and receiving antennas in a wireless installation.

FIREWALL: A network component that uses special protocols to monitor and restrict requested services, the data they contain, and the direction of information flow.

MALWARE: An unsolicited program that is usually installed secretly or without the user’s knowledge. These programs can harm the system.

MULTICAST: Sending data packets from a sender to a defined group of receivers.

PACKET: A set of binary data typically sent over Ethernet connections. It is often compared to an envelope.

ROUTER: A connecting element that acts on layer 3 of the ISO/OSI reference model between different networks.

SCADA: Acronym for supervisory control and data acquisition. SCADA systems monitor, manage, and control equipment in many industries, and include data transfer between a central host computer and a number of remote field devices.
   
SPREAD SPECTRUM: A method of transmitting a wireless signal by “spreading” it over a broad range of frequencies, one much wider than the minimum bandwidth needed to transmit.

SWITCH: Switches connect areas of the network that operate at different speeds, for example, or keep areas with very high traffic separate from other areas of the network.

TRANSMISSION SPEED: The transmission speed is the number of bits that are transmitted on one unit of time.

WIRELESSHART: A wireless sensor networking technology based on the Highway Addressable Remote Transducer (HART) protocol.

YAGI: A simple dipole antenna with elements placed along the bottom.

Source: Phoenix Contact, www.phoenixcontact.com/us, a supplier of industrial connection & automation technology.