Internet Protocol -
The internet protocol (IP) is the method or protocol by which data is sent from one computer to another on the internet.
The Internet Protocol is a protocol used for communicating data across packet switched netwaork.
Each computer (known as host) an internet has atleast ane IP address which uniquely identifies it from all other computers on the internet. When you send or recieve data (for eg. Email or a web page) the msg gets divided into little chunks called Packets. Each of these packets contains both sender and reciever address.
Because a msg is divided into no of Packets each packet can, if necessary, be sent by a different route across the internet. Packets can be arrived in differnt order than the order they were sent. The Internet Protocol just delivers them. It's upto another protocol TCP to put them back in right order.
No circuit setup is needed before a host tries to send packets to a host it has previously not communicated with (this is the point of packet switcjed network), thus IP is a connectionless protocol.
What is Packet Switched Network?
It describes the type of a network in which relatively samll units of data called packets are routed through a network based on destinition address contained within each packet. Breaking communication down into packets allow same data path to be shared among many users in the network. This type of communication between sender and reciever is known as connectionless which is in contrast with circuit switched (for eg. Telefone network).
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