10.1. NETWORK-BASED INFORMATION PROCESSING TECHNOLOGIES
Data transfer between computers has probably existed since the very beginning of computer science. It enables collaboration between individual computers, solving a task with the resources of several computers, assigning each of the computers to perform a single function, sharing resources and solving multiple other problems.
Definition
Computer network (CN) - a data processing system that includes a geographically distributed system of computers and their terminals, united in a single system.
Networking allows computers to share:
• hardware (hard drives, printers, communication devices, etc.);
• software tools (word processors, spreadsheet processors, database management systems, etc.);
• multiuser systems (e-mail, teleconferences, database-based information systems, e.g. databases for banking operations, etc.).
The main characteristics of networks include:
• bandwidth - the maximum amount of data transmitted by the network per unit of time; bandwidth is measured in megabits per second
(Mbps);
• network response time - the time it takes the network devices and software to prepare for data transmission over a given channel; network response time is measured in milliseconds (ms).
There exist several classifications of computer networks. By territorial spread there are:
• LAN, Local Area Network);
• Metropolitan Area Network (MAN, Metropolitan Area Network);
• WAN, Wide Area Network.
Computer networks in terms of information transfer speed can be classified as:
• low-speed, up to 10 Mbps;
• medium-speed - up to 100 Mbps;
• high-speed, over 100 Mbps.
The following distinctive features of the local network can be formulated: