Circuit switching is a telecommunication technology by which two network nodes establish a dedicated communications channel before communication takes place whereas packet switching does not need a dedicated network to communicate, all network users can share the same paths at the same time.
In Circuit switching to provide communication among N computers, there must be a connection for each computer and at least N/2 independent paths.whereas in Packet switching a network must have a connection for each computer but only requires one path that is shared. Hence lower cost in Packet switching due to sharing of resources Circuit switching is more expensive because of the dedicated connection for example in PSTN (Public Switched Telephone Network) means one is renting the lines when making a call. However in Packet switching cost is shared for example VOIP where you can use the network even if there are other people using it at the same time.
Circuit switching is reliable in that you have a circuit dedicated to you during a session hence no information is lost where as in packet switching the circuit is open for all hence there is a possibility of congestion and delays in passing on the packets. Circuit switching is old and expensive for example in the case of PSTN whereas packet switching is modern. Examples of circuit switching include:•Public Switched Telephone Network(PSTN),•Integrated Services Digital Network(ISDN),•Circuit Switched Data Examples of Packet Switching,•VOIP •Newer mobile phone technologies e. g GPRS,•Datagram packet switching (packets are routed individually and the packets include complete addressing information) examples here include Ethernet, IP and UDP ,•Connection oriented packet switching - the packets include connection identifier and are delivered in order.
Examples include Frame relay and Multiprotocol Label Switching (MPLS).
