IP Passthrough allows a device connected to an Ethernet LAN port on the AirLink router to be assigned the IPv4 address of the cellular WAN interface. This bypasses the router’s Network Address Translation (NAT) layer, effectively allowing the connected device to act as if it is directly connected to the internet. All incoming traffic to the public IP is directed to the connected device.
To configure IP Passthrough, go to Networking > General > WAN Services.
To configure IP Passthrough:
Go to Networking > General > WAN Services.
Click CREATE WAN SERVICE to create a new service, or at the end of a table row, click and select Edit.
Configure the following fields for IP Passthrough:
SETTING | DESCRIPTION | DEFAULT SETTING | RANGE |
---|---|---|---|
IPV4 PASSTHROUGH | Enables IP Passthrough to the specified Ethernet LAN port | Off | Off,<list of available ethernet LAN ports> |
IPV4 PASSTHROUGH - UNSOLICITED INCOMING | Allow or Deny unsolicited incoming packets to the passthrough device. | Allow | Allow,Deny |
IPV4 PASSTHROUGH - ICMP GATEWAY REACHABILITY | Intercept ICMP packets and redirect to the router instead of fowarding to the connected passthrough device. | Disabled | Disabled,Enabled |
IPV4 PASSTHROUGH - NEXT HOP GATEWAY IP ASSIGNMENT | By default the passthrough device will receive a next hop IP within the same subnet of the assigned WAN IP via DHCP. The next hop IP will be a.b.c.1, or a.b.c.254 if a.b.c.1 is the WAN IP. If necessary, override the next hop IP manually. | Inside WAN Subnet | Inside WAN Subnet,Manually Configured IP |
IPV4 PASSTHROUGH - NEXT HOP GATEWAY MANUAL IP ASSIGNMENT | Only displayed when NEXT HOP GATEWAY IP ASSIGNMENT is set to Manually Configured IP. Manually set the next hop router IP via DHCP for the connected IPv4 Passthrough Device. | Blank | IPv4 address |
IPV4 PASSTHROUGH - DHCP OPTION SUBNET PREFIX |
Sets the subnet mask of the WAN IP. When set to Auto, for cellular devices this is 32. |
Custom | Auto,Custom |
IPV4 PASSTHROUGH - PREFIX LENGTH | Prefix length. Only available when DHCP OPTION SUBNET PREFIX is set to Custom | 24 | Prefix value |
IPV4 PASSTHROUGH - DESTINATION ALLOCATION MODE | The destination IP address for the traffic | First Host |
|
IPV4 PASSTHROUGH - DESTINATION MAC | Only displayed when DESTINATION ALLOCATION MODE is set to Select from List or Manual MAC entry. The hardware MAC address of the connecting device. | blank |
IPv4 passthrough can be used in conjunction with IPv6 XLAT. See Configuring IPv6 XLAT for more information.