• A distributed computer system consists of several computer systems connected through a network for the communication and resource sharing purpose.
  • A distributed system is a system consisting of two or more nodes, where each node is a computer system with its own memory and some networking hardware.
  • It is used to share the information and it provides a rich set of features to users like accessing different resources available at another computers.
  • However, the possibility of network failures or failure of individual computer system complicates functioning of the operating system.
  • Networks vary by protocols and distances between two computers (it is a set of rules which offers conversation between two computer systems = protocol) Ex. TCP/IP.
  • IP is the most common network protocol. Most operating systems support TCP and IP including WINDOWS and UNIX. A network protocol simply needs an interface card, network adapter driver to manage it. Networks are divided on the base of the distance between the computers.
  1. LAN – Local area network exists within a room, a floor or a building.
  2. MAN– Metropolitan area network is a type of network, which exists within buildings of different cities.
  3. WAN– Wide area network exists between different countries. Ex. Internet – The media to carry network equally varied. The network media includes copper wires, co-axial cables, fiber optics and satellites.