Difference between revisions of "Port"

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(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...)
 
imported>ThorstenStaerk
 
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To find out what ports are open (listening) on your system, use [[nmap]].
 
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.
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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 create a socket on your system, use [[netcat]].
  
To test a port use [[telnet]].
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To test a port use [[telnet]]. For example testing the IMAP port 143 is described [[Testing IMAP via telnet|here]].

Latest revision as of 17:45, 3 July 2011

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. For example testing the IMAP port 143 is described here.