We currently service a client that has a PIX firewall that connects to multiple, separate outside vendors via IPSEC VPN. The VPN connections are mission critical and if for any reason the VPN device or the internet connection (currently only a T1) goes down, the business goes down too. We're looking for a solution that allows dual-ISP, failover, and load balancing. I see that there are several ASA models as well as the IOS that support this but what I'm confused about is what are the requirements for the other end of the VPN, keeping in mind that the other end will always be an outside vendor and out of our control. Current VPN endpoints for outside vendors are to devices like VPN 3000 Concentrator, Sonicwall, etc. that likely do not support any type of fail-over, trunking, load-balancing. Is this just not possible?