Where can i find a list of ports and what they do?

IANA (Internet Assigned Number Assocation, www.iana.org) maintains the most comprehensive (and official) list of well known and registered port numbers. The current location of the most up to date list is at http://www.isi.edu/in-notes/iana/assignments/port-numbers.

Is it possible to choose any free port for connections?

yep
well
i don;t think you can use 0

1-32767, as long as its not in use

You should really try to use ports above 1024, and if you call bind with a port number of 0, it should bind the socket to an anonymous port (some random, but free port on the interface).

Is there any program (for windows) that can monitor a port and return all information that passes thru that port as readable strings?

Network Monitor would work. When looking at the data, the bottom pane shows the binary data and if there are plain-text strings, it will show that too.

Tell me more about Network Monitor... is it part of the NT system, is it freeware/shareware etc? If so where can i dl it

There are a couple versions. One comes with Windows NT/2000. Another version comes with SMS Server that has the added ability of being able to view packets to/from another machine.

A search on yahoo for "Network Monitor" will return several hits I''m sure.

- One comes with Windows NT/2000.


I found network monitor as a protocol and i installed that, but I cant find any program to monitor any ports. I''ve searched my harddrive for "net monitor" and "net mon" etc. I''ve searched the net for info, my local help files etc. I''m an utter dork, and I need more help!