Interview Questions

How do I know which application uses what port?

Java Security,Windows code security, Windows Server 2003 Security,Internet Explorer 7 Security and Internet Firewalls questions and answers


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How do I know which application uses what port?

There are several lists outlining the ``reserved'' and ``well known'' ports, as well as ``commonly used'' ports, and the best one is: ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers. For those of you still reading RFC 1700 to find out what port number does what, STOP DOING IT. It is horribly out of date, and it won't be less so tomorrow.

Now, as for trusting this information: These lists do not, in any way, constitute any kind of holy bible on which ports do what.

Wait, let me rephrase that: THERE IS NO WAY OF RELIABLY DETERMINING WHAT PORT DOES WHAT SIMPLY BY LOOKING IN A LIST.

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