About > Glossary

Bit - Binary digit in the binary numbering system. Its value can be 0 or 1. In an 8-bit character scheme, it takes 8 bits to make a byte (character) of data.

Bytes - A collection of eight bits that represent a character, letter or punctuation mark.

Cable - Transmission medium of copper wire or optical fiber wrapped in a protective cover.

Client/Server - A networking system in which one or more file servers (Server) provide services; such as network management, application and centralized data storage for workstations (Clients).

DA – data access.

Internet - A global network of networks used to exchange information using the TCP/IP protocol. It allows for electronic mail and the accessing ad retrieval of information from remote sources.

IP, Internet Protocol - The Internet Protocol, usually referred to as the TCP/IP protocol stack, allows computers residing on different networks to connect across gateways on wide-area networks. Each node on an IP network is assigned an IP address, typically expressed as 'xx.xx.xx.xx'.

IP address (Internet Protocol address) - The address of a computer attached to a TCP/IP network. Every client and server station must have a unique IP address. Client workstations have either a permanent address or one that is dynamically assigned to them each dial-up session. IP addresses are written as four sets of numbers separated by periods; for example, 198.63.211.24.

LAN (Local Area Network) - A network connecting computers in a relatively small area such as a building.

OPC (OLE for Process Control) – a set of universally accepted specifications providing a universal data exchange mechanism in control and management systems.

OPC Alarms and Events - the OPC interface for access to alarm and event data.

OPC Data Access - the OPC interface for access to real-time data.

OPC DA - see OPC Data Access.

OPC Historical Data Access - the OPC interface for access to archived data.

OPC HDA - see OPC Historical Data Access.

PC - abbreviation for a Personal Computer.

TCP/IP, Transport Control Protocol / Internet Protocol - TCP and IP are communications protocols, that is, structured languages in which data is communicated between one process and another, and between one network and another. TCP/IP is implemented in a multi-level layered structure. TCP/IP is the 'glue' that that ties together the many heterogeneous networks that make up the Internet.