Communicate?
Devices connected via WiFi, Ethernet, ADSL, F-O, UHF, Satellite etc; LAN traffic handled by switches, Internet traffic
handled by routers; network devices work together to find optimal path; need to cope w/ 'lost' data, cope w/ congestion
or broken link redirection, encryption/decryption, new technology integration, range of different media sent
Protocols - rule set, designed for particular task, allows new technology working alongside existing protocols (2G, 3G...)