P-2302HW/HWL-P1 Series User’s Guide

Figure 101 PSTN to PSTN Example - Incoming Authentication

13.9.4 Call Progression

The call is initiated by the manager dialing into the headquarter’s ZyXEL Device via PSTN. In this scenario a VoIP link is established between headquarters and the branch office and then the call is forwarded to Sales1 using PSTN.

Table 78 PSTN to PSTN: VoIP Trunking Call Progression

MANAGER

HEADQUARTERS

BRANCH OFFICE

SALES1

 

 

 

 

The manager dials the PSTN number of the headquarters’

 

 

ZyXEL Device. (222-222-2222)

 

 

 

 

 

The ZyXEL Device receives the call and sends a ringback

 

 

alert tone to indicate to the caller that VoIP trunking is

 

 

enabled.

 

 

 

 

 

 

The manager dials the PSTN number of Sales1 (555-555-

 

 

1234).

 

 

 

 

 

 

The ZyXEL Device prompts the manager to enter the PIN in

 

 

order to allow VoIP trunking.

 

 

 

 

 

The manager dials the PIN (12345).

 

 

 

 

 

 

 

The ZyXEL Device confirms the password and allows for VoIP trunking.

 

 

The ZyXEL Device inspects the phone number against call rules. Since the number

 

 

starts with the pattern (5555), it uses the account (CityB) associated with this pattern to

 

 

connect the call to the remote peer device at the branch office.

 

 

 

 

 

The remote peer device inspects the number and requests authentication in order to

 

 

forward the call.

 

 

 

 

 

 

Chapter 13 VoIP Trunking

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