ZyXEL Communications ISG50 User Manual
Chapter 30 Outbound Trunk Group
ISG50 User’s Guide
479
AA (Auto Attendant)
After calling the number, the caller is prompted to dial the extension number.
Figure 307
Auto Attendant (AA) Example
DDI (Direct Dial In)
DDI (also called DID, Direct Inward Dial) is a feature that maps a public number to an extension
number. DDI enables a caller to call an extension number without going through an operator. When
people give out their contact number and say it's a “direct line”, often what they mean is that it's a
DDI number.
number. DDI enables a caller to call an extension number without going through an operator. When
people give out their contact number and say it's a “direct line”, often what they mean is that it's a
DDI number.
For example, your company has 10 phone numbers (555-123456~555-123465). You can choose
555-123456 to be the directory number (the company’s representative phone number) and map
the others to extensions using DDI. Define 2 digits (from right to left) for the DDI mask. Associate
“57” to an extension number (for example, 1111).
555-123456 to be the directory number (the company’s representative phone number) and map
the others to extensions using DDI. Define 2 digits (from right to left) for the DDI mask. Associate
“57” to an extension number (for example, 1111).
Figure 308
DDI Example
ISG
ISDN
Please
extension!
dial
6 0 1 2
555-123456
6012
AA
BRI
Caller number: 999654321
Callee number: 555123457
Callee number: 555123457
Caller number: 999654321
Callee number: 1111
Caller number: 1111
Callee number: 999654321
Caller number: 555123457
Callee number: 999654321
999654321
DDI Mask = 2
... So, DDI Number = 57
08
1234
DDI Mapping Table
Caller number: 7777
Callee number: 999654321
Caller number: 555123456
Callee number: 999654321
A
B
C
ISDN
ISG