Using a Netgear DG834Gv3 as an ADSL modem

Last week I treated myself to a new NAS device (cost: £££; good backups: priceless) which also has a built-in 802.11N wireless access point. Consequently I needed to find a way to make my Netgear DG834Gv3 act as a pure ADSL modem to avoid the headache of two layers of NAT.

While not documented/officially supported, the Netgear can be used as a pure modem (sometimes called “Bridge-only Mode” by other vendors) using a hidden link and selecting “modem-only” mode:

This was trivial to find using the leading search engine, but it does not work using the default settings in the UK—you must also change the ADSL multiplex method to “LLC” on the “ADSL Settings” page 1. Having done this, connect the second wireless AP/router/computer to the Netgear via ethernet and configure it to connect to the Internet using PPPoE.

  1. Confusingly this is the opposite to the standard setting used when configuring UK ADSL which would normally be VC-based multiplexing[]