Draytek Vigor IPPBX 2820 Series User Manual page 58

Operand Number
Min Len
Max Len
Trunk
for the prefix number is set with 886.
Replace - When you choose this mode, the OP number will
be replaced by the prefix number for calling out through the
specific VoIP interface. Take the above picture (Prefix
Table Setup web page) as an example, the prefix number of
03 will be replaced by 8863. For example: dial number of
"031111111" will be changed to "88631111111" and sent
to SIP server.
The front number you type here is the first part of the
account number that you want to execute special function
(according to the chosen mode) by using the prefix number.
Set the minimal length of the dial number for applying the
prefix number settings. Take the above picture (Prefix
Table Setup web page) as an example, if the dial number is
between 7 and 9, that number can apply the prefix number
settings here.
Set the maximum length of the dial number for applying the
prefix number settings.
Choose the one that you want to enable the match prefix
settings from the saved SIP accounts.
Please set up one SIP account first to make this route
available. This item will be changed according to the port
settings configured in IP PBX>>PBX System>>Phone
Settings and IP PBX>>Trunks>>SIP Trunk.
50
VigorIPPBX 2820 Series User's Guide