ZyXEL ISG50-PSTN User Guide - Page 479

Chapter 30 Outbound Trunk Group AA (Auto Attendant) After calling the number, the caller is prompted to dial the extension number. Figure 307 Auto Attendant (AA) Example Please AA dial extension! 6012 6012 ISG 555-123456 ISDN 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. 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). Figure 308 DDI Example DDI Mask = 2 ... So, DDI Number = 57 DDI Mapping Table 08 1234 ISG Caller number: 999654321 Callee number: 1111 BRI ISDN A Caller number: 999654321 Callee number: 555123457 Caller number: 1111 Callee number: 999654321 B Caller number: 555123457 Callee number: 999654321 Caller number: 7777 Callee number: 999654321 C Caller number: 555123456 Callee number: 999654321 999654321 ISG50 User's Guide 479