SI-PROFINET RT User Guide
45
Issue Number: 2
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Subnet
: A part of a network that has IP addresses in the same range. Devices on the
same subnet may communicate directly with other devices on the same subnet without
the use of a gateway.
Subnet mask
: Defines which part of the IP address constitutes the subnet address and
which part constitutes the host device address.
Switch
: A device that allows Ethernet devices to be interconnected.
Synchronous Transmission
: A constant time interval between characters is used to
ensure that all data communications equipment is in step with each other. The opposite
of asynchronous transmission, synchronous transmission, does not use start-stop bits
surrounding each byte, but relies on the transmitter and receiver to be functioning at a
fixed rate of transmission, thereby being a more efficient method of data
communication.
TCP (Transmission Control Protocol)
: This protocol is responsible for ensuring that
the data on the network reaches its destination.
TDM (Time Division Multiplexer)
: A multiplexer designed to apportion its composite
link time between its available channels, interleaving data at a higher speed on the main
or multiplexed channel. The data signals are then separated to restore the data to the
individual input channels.
URL (Uniform Resource Locator)
: A method used to give a web site a friendly name
such as www.controltechniques.com as an alternative to an IP address.
VPN (Virtual Private Network)
: A method of using a non-secure or public network that
allows devices to be connected together as if they were a part of a private network.
Word
: A collection of 16 binary digits.
XML (Extensible Markup Language)
: A document definition that is intended to store
and transfer data between applications.