A switched network consists of a series of interlinked nodes, called switches. Traditionally’ three methods of switching have been important: circuit switching, packet switching, and message switching.
We can divide today’s networks into three broad categories: circuit-switched networks, packet-switched networks, and message-switched. Packet-switched networks can also be divided into two subcategories: virtual-circuit networks and datagram networks
A circuit-switched network is made of a set of switches connected by physical links, in which each link is divided into n channels. Circuit switching takes place at the physical layer. In circuit switching, the resources need to be reserved during the setup phase; the resources remain dedicated for the entire duration of data transfer phase until the teardown phase.
In packet switching, there is no resource allocation for a packet. This means that there is no reserved bandwidth on the links, and there is no scheduled processing time for each packet. Resources are allocated on demand.
In a datagram network, each packet is treated independently of all others. Packets in this approach are referred to as datagrams. There are no setup or teardown phases.
A virtual-circuit network is a cross between a circuit-switched network and a datagram network. It has some characteristics of both.
Circuit switching uses either of two technologies: the space-division switch or the time-division switch.
A switch in a packet-switched network has a different structure from a switch used in a circuit-switched network.We can say that a packet switch has four types of components: input ports, output ports, a routing processor, and switching fabric.
You may be interested in:
Data Communication and Networking MCQs by Behrouz A Forouzan.
Data Communication and Networking Randomly Picked MCQs
Fundamental of Networking online tests
Data Communication and Networking online tests
Data Communication and Networking Short Questions Answers
Data communication and networking MCQs PDF File for Download