Netcat is a networking service used for reading or writing from TCP and UDP sockets using an easy interface. Netcat can be used directly by other programs and scripts. It has network debugging and investigation tools.
Ncat is a general-purpose command-line tool for reading, writing, redirecting, and encrypting data across a network. It handles a wide variety of security testing and administration tasks. Ncat is suitable for interactive uses.
Chatting Using Netcat
If chatting has to be done between two machines A and B, do the following:
In machine A,type the following command:
$ nc -l <port_no.>
And in the machine B, execute the command
$ nc <ip_address of A> <port_no.>
Now machines A and B can chat.
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