VPN Load Balancing with DrayTek Routers
VPN Load balancing allows numerous VPN connections to exist between two sites, and their configuration over multiple WAN connections. This is used to provide both a larger capacity network pipe between the two sites as well as support redundancy should one of the WAN connections fail.
VPN load balancing is a process involving the combination of two individual VPN connections as a single VPN trunk. VPN traffic is then transmitted over both links, with each individual VPN link in the trunk connection determined by the Real Time Bandwidth of each link, which shares the VPN traffic load.
This is a useful feature when a site’s ADSL connection limits network speed. For example, a VPN load balanced connection can be established between head and remote offices over two ADSL links, which effectively doubles the link capacity between the two sites.
The two WAN connections may also come from separate ISP’s, meaning a VPN connection can be maintained over a second WAN connection should one of the providers fail.
Some devices, such as the Vigor3200 and the Vigor3300 can use 4 WAN connections to create a much larger VPN trunk between two interconnected sites, as outlined below. In the diagram, two VPN trunks are established (one for each LAN subnet) and then combined into one large VPN trunk.
Routers supporting VPN load balancing are the Vigor2850, 2930, 2955, 3200, 3300 and the eagerly awaited Vigor3900 and Vigor2960 series routers.
Details on how to configure VPN load balance using the Vigor3200 is available from:http://www.draytek.com/user/SupportAppnotesDetail.php?ID=973
This feature has recently been advertised in the printed media. A copy of this publication is available from our website: