PingGraph is a monitoring tool tailored to the needs of network administrators. PingGraph gathers ping response times from multiple host systems, and draws graphs of ping response over time, as well as estimating the current bandwidth available on the connection.
Scrolling graphs may be shown for a wide range of time scales from 10 minutes to a year, allowing you to quickly identify trends, connectivity problems and packet loss across your network. Data is saved in a simple XML format for easy use by external applications. The log file size is automatically managed so you don't have to worry so much about disk space.

The license of this software is Free Trial Software, the price is $39, you can free download and get a free trial.