A packet-switched network (PSN) is a kind of computer communications network that sends data in the form of small packets. It allows the sender to send data or network packets to the source and destination node over an internet network channel that is transferred between multiple users and/or applications. A packet-switched is also called a connectionless network, as it does not create an endless connection between a source and destination points.
How Packet Switching Works:
In packet switching, the network packet is part of a file. The packet includes one letter of that email and the path of the email. It also includes a tiny chip of the letter next to it, in case that letter is lost. The packets are then transferred to the internet. The packets can be returned to many nodes and switches, going all the way around the world if they have to, each going their own different ways as internet traffic conditions allow. The data, sent at nearly the speed of light, makes it to its destination in milliseconds.
Hop in Networking:
In computer networking, a hop is the duration of the trip of a data packet when a packet is transferred from a source point to the destination point. Data packets pass via routers as they cross source and destination. The hop count is defined as the number of network devices by which the data packets passes from source to destination which is depending on routing protocol, It may include the source/destination. The first hop is counted as hop 0 or hop 1.
Network technologies in PSN:
There are many network technologies in PSN. Some of them are given below:
- CS: TDM, PDH, SDH, OTN
- CO: ATM, FR, MPLS, TCP/IP, SCTP/IP
- CL: UDP/IP, IPX, Ethernet, CLNP
Connectionless Forwarding:
A Packet Switched Network is connectionless (CL) for the following reasons:
- When there is no setup is needed before transmitting a packet, each router makes an independent forwarding decision.
- When Packets are self-describing packets are inserted anywhere and will be properly forwarded.
- When IP forwarding is detailed in RFC 1812 hundreds of software cycles per packet.
