Bear in mind though that all you'll be getting is whatever IP address the last proxy in the request chain was using at the time. IP addresses do not identify machines. IP addresses are assigned to interfaces. One machine may have multiple interfaces (even the simplest setup will typically have at least two interfaces: 127.0.0.1 for the loopback interface is also an IP address). One interface may have multiple IP addresses. And IP addresses may move.

I have 20 machines connected through LAN with a single gateway. I need to track/log those 20 machines activity from the gateway machine(I just need to log what are all the websites requested, and from which machine that website was requested). Can I do it with Perl script. If yes, can you please guide me.

You've already posted this question as a new thread, which already has an answer. Please read PerlMonks for the Absolute Beginner and How do I post a question effectively?.

What is the server serving? Someone else assumed it was a web server, but I don't see that in your request. This does matter. If you can hack up the source for the server, then the easiest command is  getpeername() . If not, you'll have to go through some secondary thing like scanning log files or running  netstat .

- doug