VPNs (Virtual Private Networks) are becoming a critical business tool, providing remote and mobile staff with access to their email, files and applications. This increased dependency on access to business information from anywhere creates a significant risk for a business should the VPN system fail.With no remote access mobile sales staff can’t place orders and action customer mails. Staff in remote locations may not be able to process shipments. All this can lead to significant interruption of business and result in significant losses to a business.A VPN system outage can be caused by the VPN hardware failing or the failure of communications links. The time to recover from an outage may depend on how quickly the technology supplier can provide a replacement unit or how quickly communications services can be restored. As a business may have little or no control over how long a resolution f the issue may take, the prudent approach is to ensure that VPN can recover immediately from the failure of any single component by implementing a highly-available VPN.The normal approach to implementing a highly available VPN is to purchase two VPN hardware units and to configure them as a highly available pair using vendor supplied technology or a third party solution. With this approach, when one unit fails, the other unit will be available to provide VPN services. To allow for communication failures, the normal approach if possible is to install two different access circuits from two different providers. Using different providers removes the risk of a single operator having a fault that impacts each circuit. If a circuit fails, remote users will have to re-establish connectivity via the new circuit. The re-establishment of connectivity is normally done by users selecting an alternative VPN server. Another approach is to provide multiple Internet routes to the VPN servers although this is much more complex approach.An alternative to doubling up on hardware and incurring the associated cost is to use a hosted VPN service that delivers high availability VPN without incurring the cost of doubling up on VPN Hardware. With a hosted VPN service, high availability is provided by installing the VPN server software on more than one existing Windows server. As hosted services use the Internet, low cost Internet circuits can be sourced from different provider giving resilience against failure of an Internet link. Hosted VPN Services provide transparent failover for the remote users with no disconnect and reconnect required.When considering a highly available VPN solution, consider all the factors including the complexity of implementation and management, how transparently the failover is for remote users and how much any solution may cost in the long term.