Note for 1 & 1 VDSL users

I am also very pleased with the VDSL router (see, however, the update below!), The I operate exclusively as VDSL modem in front of a hardware firewall. The configuration as a modem together with a VDSL line Telekom is relatively simple. Here are the steps (starting from the factory settings):

1) Network -> WAN -> Internet Connection => delete the only profile
2) Under Network -> WAN -> Layer2Interface => delete the only profile and a new one with 'Add' Create with VLAN MUX Mode (no QoS)
3) Network -> WAN -> Internet Connection => a new mess with Bridging, VLAN ID tag ... (tick) and place each one for 7 802.P and 802.Q
Take> Enable DHCP (hook) - 4) Finally, under Network -> LAN

This applies to Telekom VDSL (without Entertain) and 1 & 1 VDSL connections (if this is handled by the Telekom).

It is important that you have previously updated the firmware to the state 0909!
Very important for users of our 1 & 1 VDSL connection who have previously used the 1 & 1 Fritzbox router: If you want to dial with the Zyxel modem using PPPoE, you have to observe during your internet access code prefixed 'H' Add otherwise the dial does not work !! So the user ID must then have the form H1und1 / ab1234-123 (at) online.de
Then slap with the dial ;-)

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Update: (from 20/09/2013)

As I now had to realize from their own experience and also got approved by ZyXEL support, the router as VDSL modem not IPv6 capable. So if you are behind the modem operates a firewall, the IPv6 capable, so it can lead to problems (like mine). Once I have the ZyXEL P-870H to replace an old W920V of Telekom (configured as a pure VDSL modem), there are no more problems. Too Bad ...