I have adquired reciently a Cisco 857 router. I want to do a VPN site to site.
I have configured the interface ATM0.1 with "ip unnumbered" to VLAN 1. I haven't configured the router to enable NAT or PAT. The VLAN 1 is configured with one Ip public Address of my ISP. Behind the cisco router, I have a Zywall 5, this device is my VPN gateway. Initially, it works fine with other soho router but it blocked often, for this reason, I decided to change this one for a cisco router.
My problem now is that the router cisco doesn't permit the VPN establishment.
Do I need enable IPSEC pass-through?, How can I do this?
Thanks in advance!!