Dynalink ADSL Router/ RTA770 - Manual (Page 10)

ADSL Router Quick Set-up Guide
To set up IP extension, go to Advanced > Internet. Click on the "modify icon"
under Edit:
The next screen displays VPI and VCI as 8 and 35. Do not change these numbers.
Go Next. Select PPPoA VC MUX or PPPoE LLC/SNAP. If your ISP did not specify
PPPoE you can assume it is PPPoA. Go Next.
On the next screen untick Enable NAT, and tick PPP IP extension as illustrated.
Go Next.