In decentralized company structures that rely on VPN for networking the various locations, the availability of the central VPN gateway is of particular significance. The company-wide communications only remain reliable as long as these central dial-in nodes are working properly.
With the option of configuring several "remote gateway" addresses as the "dynamic VPN end point" for a VPN connection, VPN gateways offer a high level of availability by using redundant devices. This involves multiple gateways at the headquarters being set up with identical VPN configurations. On location at the branch sites, all of these available gateways are entered as possible remote sites for the VPN connection. If one of the gateways is unavailable, the remote router automatically redirects the request to one of the other routers.
To ensure that the computers in the LAN at the headquarters know which VPN gateway it to be used to reach a particular branch site, the outband router currently connected to the remote site is propagated via RIPv2 to the network at the headquarters.
