Im having some problems lately with our new site network configuration.
We have there new Cisco 891 router and from isp we have Zyxel P-660HN-T1A router/modem as isp connection termination and one public ip from isp.
Problem is, how to setup router for this to work with zyxell? we want to use GRE tunnels to create site to site vpn, but im completly lost.
Should zyxell be in routing/bridge mode?
Any thoughts please?