To explain this, let’s define the expenses involved in a communication circuit switched. Earlier conventional telephony, in mid-1960, each call must have a dedicated cable going from one end to the other communication throughout the time that lasted the same. So if for example a person located in Argentina had to make a call to another person in Spain switches your telephone operator would connect cables along the entire route to form a path between the two ends of the communication.

In this case if the call lasted 10 minutes commutated those cables running along the entire route between Spain and Argentina along the length of the conversation would be used. This made long-distance communications were very expensive.


Today telephone communications are much more efficient for that cost less. The voices are digitized, and your voice, can travel along with many other girders of a fiber optic cable for most of the way (still a dedicated piece of wire, which is going right into your home). Those calls are transmitted to a quality of 64kb per second (kbps) in each direction, for a total transmission of 128kb (64kb 64kb back and back). As 8KB exist in a kilobyte (KB), this is transacted in a transmission of 16KB per second that the circuit is open, and 960KB every minute is open. Then, in a communication of 10 minutes, the total transmitted serious 9,600KB, which is roughly equivalent to 10 megs. If you looked at a typical conversation you would realize easily that much of this information is wasted.


Priate’re talking, the other party is listening, which means that only half of the connection is in use at a given time. Based on that, we can deduce that could cut the size of the conversation just half 4.7MB bone while maintaining the same quality of communication.

In addition, a lot of time in conversations is dead time, time that neither speech. If we could remove these time intervals died size even smaller serious conversation. So instead of sending a continuous string of bits (both of silence or noise), what if we only send packets at times that noise occurs, when created. That is the basis of packet switching, the alternative to packet switching.