ip
IPv4 address for the customer gateway device's outside interface. The address must be static. If `OutsideIpAddressType` in your VPN connection options is set to `PrivateIpv4`, you can use an RFC6598 or RFC1918 private IPv4 address. If `OutsideIpAddressType` is set to `PublicIpv4`, you can use a public IPv4 address.