Packets are routed to their destination through the most expedient route. The packets of a single message may follow different routes. The destination computer reassembles the packets into their appropriate sequence. Packet switching is used to optimise the use of the bandwidth. Plain old telephone service.
Radio frequencies are electromagnetic signals which range from microwave to radio in length.
A conference between different locations where the communication links are made between orbiting satellites and various points on Earth. Communications satellites provide telephone,television, and data services between widely separated locations such as universities or television stations in different cities. The technique involves the transmission of signals from an Earth station to a satellite. The satellite has equipment that receives the signals, amplifies them, and transmits them to Earth. Receiving stations then pick up the signals and provide the communications link.