• A Network is a way of connecting different computers to allow data and message passing, and resource sharing.
• Early communication techniques included telegraphs (with morris code), telephones and teletypes.
- allows shared computers and peripherals
- provides communication and cooperation tools for people and computers
- increases reliability by having alternate computers available
- decreases isolation of many computers
- allows remote access to databases and libraries
- distributed computational facilities
- remote control of applications
• The relationship between various network types is shown below
• The Star Network topology uses many connections to a central server
• When all computers are connected to the same network cable, there are a number of structures which may be used. The bus topology below is simpler, and the tree topology is more flexible and versatile. This approach uses a single cable which is easy to add to
• The ring topology below shows a closed loop of cable which can be simple to implement, but limited in capabilities
• An enhanced ring topology is pictured below
• The figure below shows two ring networks, with a few possible devices hooked to them.
