We currently use a SF VPN to deliver fixed IP for our cellular routers. We do this by NAT mapping a public IP to a private IP on our Balance 710 and delivering to our router over the SF VPN. This works great and we have many customers who then create their own L3 VPN’s over this solution from their connected device back to their own central server. However we have been trying to make this work with a LAN to LAN VPN between a Cisco (on a FTTC with fixed IP) and a customers Draytek (connected to a BR1 using the above fixed IP methodology) but the session connects and then disconnect on a session timeout. This works if the Drayteek is connected to a DSL with fixed IP.
Can anyone help?