Network Terminology

Some general concepts need to be explained:

• Computer networks can be circuit switched or packet switched. The internet is mainly packet switched, and this is our focus.
• Within packet switched networks, we can still have two analogous forms of communications: connection-oriented (virtual circuit) or connectionless (datagram).
• TCP/IP is an example of the former. UDP/IP is an example of the latter.
• An everyday example of these two forms of communications are telephones (circuit switched or connection-oriented) and postal service (packet switched or connectionless).