PersianAdmins

PRTG Traffic Grapher is an easy to use Windows software for monitoring and classifying bandwidth usage. It provides system administrators with live readings and long-term usage trends for their network devices. The most common usage is bandwidth management, but you can also monitor many other aspects of your network like memory and CPU utilizations
more info
http://www.paessler.com/prtg

Download
http://rapidshare.com/files/22828314/prtg-fusion89.zip