ZyXEL Communications ISG50 ユーザーズマニュアル

 Chapter 30 Outbound Trunk Group

ISG50 User’s Guide

The screens for editing or adding FXO trunks on the ISG50 contain the same fields. Only the screen 
used to add FXO trunks is shown below. Click the Add (or Edit) icon in the FXO Trunk section of 
the Outbound Trunk Group configuration screen to view the screen as shown. 

Add/Edit FXO Trunk

Representative 
Number

This field displays the representative number configured for the trunk.

Enable Routing by 
SIP "To" Header

Select this if this auto-attendant interacts with a SIP server that uses the SIP To header to 
do the DDI/DID mapping. If this trunk outbound line group has DDI/DID mode enabled, 
using this deletes all of the this trunk outbound line group’s DDI/DID mapping settings 
and sets the DDI/DID Mask to 0.

Clear this to use the SIP request URI to do the DDI/DID mapping.

DDI/DID Mask

Enter a number (0~10) to decide the number of digits you want to enter for the next DDI/
DID number(s). 0 means you can enter any number of digits for the next DDI/DID 
number(s).

DDI/DID Mapping 
Summary

Use this section to manage the DDI/DID numbers which allow outsiders to call and reach 
extensions directly.

Add

Click this to create a new entry. Select an entry and click Add to create a new entry after 
the selected entry. See 

 for a description of adding a DDI/DID 

mapping.

Remove

To remove an entry, select it and click Remove. The ISG50 confirms you want to remove 
it before doing so.

DDI/DID Number

This field shows the DDI/DID number outsiders can call to reach the entry’s extension 
directly. 

Extension 
Number

This field shows the extension that outsiders can reach directly by calling the entry’s DDI/
DID number.

OK

Click OK to save your customized settings and exit this screen.

Cancel

Click Cancel to exit this screen without saving.

Trusted Peer Auto Attendant and DDI Setup