In a local network :
1) How can I get all availabe IP addresses?
2) How can I find out which one is active and which deactive?
3) How can I sniff (like Linux) around and see what ports are being used. The reason I'm asking this one is because I know there are some emplyees that use a networking game among themseleves and need to see which port they are using and how can I interrup it?