Configure IP Passthrough on Sierra Wireless Modems

You may need to change the following settings to allow the Public IP address assigned to you by the carrier to be used by an attached device. The settings are labeled as "Public" mode and "Private" mode in the modem LAN settings. Public Mode will provide the carrier assigned IP settings directly to an attached client device though the modem Ethernet port transparently. This mode will only support one Ethernet client device and disables all routing and firewall functionality on the modem.

AceManager Web
  1. Connect to the modem with AceManager Web. Navigate to the LAN tab
  2. From the DHCP Addressing section, choose the drop down box on the Host Connection Mode and select Ethernet Uses Public IP
  3. Set the Public Mode Subnet Mask to 255.255.255.0
  4. Apply the change to the modem and re-boot


The modem will now pass addressing information from the carrier to an attached device set to accept DHCP.  Because of the difference in Ethernet chip sets and possible synchronization issues, we recommend to "Hard code" the IP settings provided by the modem in the Ethernet settings of client devices.

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