Dial Plan - D-Link DPH-128MS User Manual

Section  - Installation
A dial plan establishes the expected number and pattern of digits
for a telephone number. This includes country codes, access codes,
area codes and all combinations of digits dialed.
Internal:
Extension numbers of three digits in length.
Local numbers:
A seven or ten digit number, which may be preceded by
an 8 or 9 if required to access an outside line.
Long distance:
An eleven digit number that consists of a 1, then a
three-digit area code, then a seven-digit number;
preceded by an 8 or 9 if required to access an outside
line.
D-Link DPH-18MS User Manual

Dial Plan