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When running netstat -a on my local machine, i see ports on the address listening. I would assume that is my local machine, except that i also see listening to specific ports.

What is the address? What is the difference between and

Below is an example of the output:

Proto  Local Address          Foreign Address        State
TCP            MyComputer1:0          LISTENING
TCP          MyComputer1:0          LISTENING
TCP          MyComputer1:0          LISTENING
TCP         MyComputer1:0          LISTENING
TCP         MyComputer1:49801      ESTABLISHED
TCP         MyComputer1:57172      TIME_WAIT
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up vote 9 down vote accepted

Listening on means that the program is listening on all IPv4 addresses assigned to the machine, whereas is the loopback address, only accessible from the same machine.

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Sweet, didn't know that. – Ciaran Feb 1 '11 at 0:10
forgive my ignorance, but what is a loopback address? – contactmatt Feb 1 '11 at 4:51
It's an address that loops back to the same machine it's on. – Ignacio Vazquez-Abrams Feb 1 '11 at 4:57

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