If you need to check on who is logged into a Windows Small Business (SBS) 2003 server via a VPN connection you can do so by using Routing and Remote Access under Start then Administrative Tools.
For analyzing the log files for information on VPN logins through the SBS 2003 server, Microsoft offers the iasparse tool, which can be found on Disc # 2 of the installation CDs. But the shareware tool, IAS Log Viewer, is better at displaying the data in a more manageable fashion.
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