Circuit-switched vs Packet-switched networks

Computer Engineering Computer Network MCA

Definitions

Circuit Switched Networks − Circuit switched networks are connection-oriented networks. Here, a dedicated route is established between the source and the destination and the entire message is transferred through it.

Packet Switched Networks − Packet switched networks are connectionless networks. Here, the message is divided and grouped into a number of units called packets that are individually routed from the source to the destination.

Comparisons

Differences with respect to technology

Serial Number	Circuit – Switching	Packet – Switching
1	It is a connection oriented network switching technique.	It is a connectionless network switching technique.
2	A dedicated path has to be established between the source and the destination before transfer of data commences. Once, the data is transmitted, the path is relinquished.	There is no need to establish a dedicated path from the source to the destination.
3	It is inflexible in nature since data packets are routed along the same dedicated path.	Each packet is routed separately. Consequently, it is flexible in nature where the different data packets follow different paths.
4	It was initially designed for voice transfer.	It was initially designed for data transfer.
5	The entire message is received in the order sent by the source.	The individual packets of the message are received out of order and so need to be reassembled at the destination.
6	It is implemented at Physical Layer.	It is implemented at Network Layer.
7	It has two approaches − Space division switching, and Time division switching	It has two approaches − Datagram, and Virtual Circuit
8	It is not a store and forward transmission.	It is store and forward transmission.
9	Data is processed and transmitted at the source only.	Data is processed and transmitted, not only at the source but at each switching station.

Differences with respect to applicability, advantages and disadvantages.

Serial Number	Circuit – Switching Networks	Packet – Switching Networks
1	They are suitable for long continuous transmission, like voice calls.	They are unsuitable for applications that cannot afford delays in communication like high quality voice calls.
2	Once a route is established between the source and the destination, the route cannot be used by any other user. This leads to poor utilization of resources.	It allows simultaneous usage of the same channel by multiple users. This guarantees better resource utilization.
3	Bandwidth requirement is high even in cases of low data volume.	It ensures better bandwidth usage as a number of packets from multiple sources can be transferred via the same link.
4	Time required to establish connection may be high.	Delay in delivery of packets is less, since packets are sent as soon as they are available.
5	Initial cost is low.	Packet switching high installation costs.
6	The protocols for delivery are relatively simpler.	They require complex protocols for delivery.
7	It is more reliable.	It is less reliable.