IP pass-through

IP pass-through creates a subnet (/29) consisting of the WAN-IP and gateway addresses. In order that the taken IP's are still reachable in the APN network, the subnet must be decreased:

Example: IP received from your APN: 10.203.1.2/17

Network: 10.203.0.0/17 HostMin: 10.203.0.1 HostMax: 10.203.127.254

Without configured optional WAN network and WAN netmask the connected device receives 10.203.1.2/29 gw 10.203.1.3. The IP's 10.203.1.1 - 10.203.1.6 are no reachable in the APN network.

Decrease subnet:
WAN network: 10.203.0.0
WAN netmask: 255.255.0.0

Network: 10.203.0.0/16
HostMin: 10.203.0.1
HostMax: 10.203.255.254

The device receives: 10.203.1.2/16 gw 10.203.128.0

The gateway is outside the APN network but the hosts are still reachable