Background

The ISA Server 2004 firewall can be configured as a VPN server or VPN gateway.
You can use the Microsoft Internet Security and Acceleration Server 2004 management console to manage almost every aspect of the VPN server configuration. The firewall manages the list of IP addresses assigned to VPN clients and places those addresses on a dedicated VPN clients network. 

VPN clients

On the Windows 2000 external client machine, right click the My Network Places icon on the desktop and click Properties. 

Double click the Make New Connection icon in the Network and Dial-up Connections window. 

Click Next on the Welcome to the Network Connection Wizard page.

On the Network Connection Type page, select the Connect to a private network through the Internet option and click Next. 

Then follow the wizard' guide.

VPN server

By default, the VPN server component is disabled. The first step is to enable the VPN server feature and configure the VPN server components.

Perform the following steps to enable and configure the ISA Server 2004 VPN Server:

Open the Microsoft Internet Security and Acceleration Server 2004 management console and expand the server name. Click on the Virtual Private Networks (VPN) node. 

Click on the Tasks tab in the Task Pane. Click the Enable VPN Client Access link.

Please go to http://www.isaserver.org/articles/2004vpnserver.html for more details.

Surely, you shall configure RADIUS server at the VPN server as the above figure showed.

Radius server

PowerRadius (provided by www.new-saga.com) can support this model. You can use PowerRadius to authenticate VPN users username/password, and can bind to their MAC address. You may have to configure separator=@ in the PowerRadius configuration file.

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