Who's on that port?

[realm174]

Here's the setup:

                             -- Computer A
                            /
Internet -- Router/Firewall
                                                         -- Computer B

Ideally, what I would like to know is if there is a way to monitor who (from the internet) is accessing a specific port on Computer A, on which an application listening to that port is already running. I would like to be able to do that from Computer B. If not, well, from Computer A will work as well.

Once a connetion is established on the application of Computer A, there's a large amount of traffic being generated (which is expected). So installing a "port monitor" would probably generate too much of an output.

What I ideally would like is an application to tell me when someone gets there, their IP, their DNS name, then to ignore that IP and not report it anymore. (no point having the same line of information 4000 times).

Does this make sense? Need any more info?

Thanks!!

Realm174