Port
From Linuxintro
Revision as of 02:55, 7 April 2009 by imported>ThorstenStaerk (New page: In [http://en.wikipedia.org/wiki/Transmission_Control_Protocol TCP] and [http://en.wikipedia.org/wiki/User_Datagram_Protocol UDP] networking, a port is a two-byte number intended to define...)
In TCP and UDP networking, a port is a two-byte number intended to define to which service network packages will be delivered. As example, port 80 is for web browsing content and port 22 is for ssh.
To find out what ports are open (listening) on your system, use nmap.
To find out what connections are established on your system, use netstat -putan or lsof -i.
To create a socket on your system, use netcat.
To test a port use telnet.
