Understanding VPN Reconnect

VPN Reconnect is a new feature of Windows 7 and Windows Server 2008 R2 that allows VPN connections to remain alive even when the underlying Internet connectivity for the connection is temporarily lost. VPN Reconnect is designed to make VPN connections more reliable by eliminating the need for users to manually reestablish their connection when it has been interrupted.

In previous versions of Windows, when Internet connectivity is lost, the VPN connection is also lost. This means that if the user was working with an application or had a document open when the interruption occurred, the user's work would be lost. This issue occurred with any of the tunneling protocols supported on previous versions of Windows, including Point-to-Point Tunneling Protocol (PPTP), Layer 2 Tunneling Protocol over IPsec (L2TP/IPsec), and SSTP.

With VPN Reconnect, however, which uses the new IKEv2 tunneling protocol with the MOBIKE extension, when the user's Internet connectivity is interrupted, the user's VPN connection remains alive, and when Internet connectivity is restored, the user can continue using her application or working with her open document. VPN Reconnect thus eliminates the need to manually reconnect mobile computers to the corporate network after Internet connectivity is interrupted, thus making it easier for mobile users to access the corporate network and perform their work over a VPN connection.

VPN Reconnect also enables new types of mobile worker scenarios. For example, consider a mobile user who is traveling on a train and using a wireless mobile broadband card to connect her laptop to the Internet and establish a VPN connection to her company's internal network. As the train leaves the station, the user moves out of range of the train station's wireless access point, and the user's Internet connectivity is temporarily lost. The train comes into range of an access point at the next stop a few minutes later, and using VPN Reconnect, the user's VPN connection is automatically and seamlessly restored and she can continue doing her work.

Other scenarios in which VPN Reconnect can benefit mobile users can include maintaining a VPN connection when the user transitions between any of the following:

• A costly, slow wireless WAN (WWAN) to a cheaper, faster wireless local area network (WLAN), such as when a user is traveling and then arrives at a customer location or at her own home
• A public wireless network and the corporate wired LAN, such as when a traveling user arrives at work

Note DirectAccess can replace the VPN as the preferred remote access method for many organizations. However, some organizations will continue to use VPNs side by side with DirectAccess, and Microsoft has improved VPN usability in Windows 7 with VPN Reconnect to meet the needs of these organizations. For more information about DirectAccess, see the section titled "Understanding DirectAccess" later in this tutorial.