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A Virtual Private Network (VPN) provides an encrypted connection (secure tunnel) from outside networks or Internet Service Providers (ISPs) to the internal network.

Q. What is a VPN?

A. A Virtual Private Network (VPN) provides an encrypted connection (secure tunnel) from outside networks or Internet Service Providers (ISPs) to the internal network.

Q. Who should use the VPN?

A. You should use the VPN if you are off-campus and need to access departmental servers and/or services that require a campus IP address. You should also use the VPN if you need to comply with federal regulations regarding data confidentiality.

Q. How does a VPN work with my computer?

A. The VPN client software is installed on your home computer or laptop. After you connect to the on-campus VPN Concentrator, the software client creates a secure tunnel. We are using Cisco Unified VPN Clients, which can be used on Windows, Mac OS X, Solaris and Linux. You will be required to authenticate with your Onyen and password.

Q. Why am I getting a "not available" error message when I use the VPN?

A. You may encounter the following error message: "The necessary VPN sub-system is not available. You will not be able to make a connection to the remote IPSec server." It is likely that the Cisco VPN service did not start. Please reboot your computer, and if the problem does not clear up, go to: Control Panel -> Administrative Tools -> Services. Look for the Cisco Systems, Inc. VPN Service and confirm that the service has started. Please also confirm that the Deterministic Network Enhancer protocol (DNE), which was installed at the same time as the VPN client, is still installed.

Q. Why am I having problems connecting using the VPN?

A. If you are still having problems connecting, look under Properties for your VPN connection and select the General tab. Make sure that "Enable Transparent Tunneling" is checked, and choose to allow IPSec over UDP. Note that if you are connecting through a router and are experiencing intermittent connectivity, you may need to uncheck "Enable Transparent Tunneling."

Q. Can I use two VPN clients at the same time?

A. No. If you have two Cisco clients installed and try to open a second instance, you will simply see the connection window. You can only have one IPSec connection at a time. Beginning a second instance of the client for Linux or Solaris will yield the following error message: "A connection already exists. You will need to disconnect before making a new connection."

Q. How should I configure my Linksys router to work with the VPN?

A. Note: The following is provided for information only. If you are using a Linksys router/firewall with your broadband connection, enable IPSec and PPTP to pass through. Also enable the "Block WAN Request" option. If you are having difficulties, try upgrading your Linksys firmware to the latest version; however, please do not upgrade beyond firmware version 1.39.2 until Linksys releases a new firmware that is compatible with the VPN client. Note that a Linksys router will allow a maximum of one VPN session at a time.

Q. Why am I having trouble uninstalling my VPN client running on Windows 2000 or XP?

A. Please see for more details on removing the VPN client if the uninstall fails for some reason.