SCADA and local area networks

Local area networks (LAN) are all about sharing information and resources. To enable all the nodes on the SCADA network to share information, they must be connected by some transmission medium. The method of connection is known as the network topology.

Nodes need to share this transmission medium in such a way as to allow all nodes access to the medium without disrupting an established sender.

A LAN is a communication path between computers, file-servers, terminals, workstations, and various other intelligent peripheral equipments, which are generally referred to as devices or hosts. A LAN allows access for devices to be shared by several users, with full connectivity between all stations on the network. A LAN is usually owned and administered by a private owner and is located within a localized group of buildings.

Ethernet is the most widely use LAN today because it is cheap and easy to use. Connection of the SCADA network to the LAN allows anyone within the company with the right software and permission, to access the system. Since the data is held in a database, the user can be limited to reading the information. Security issues are obviously a concern, but can be addressed.