ZyXEL Communications ISG50-ISDN Application Note page 49

Configure the LCR in both ISG50-1 (Main Office) and ISG50-2 (Remote Office) to let the extensions of ISG50-1 (Main Office) and ISG50-2
(Remote Office) make call to each other over Trusted Peer.
In this example, for extensions in ISG50-1 (Main Office), they need to dial 49XXXX to reach extensions in ISG50-2 (Remote Office).
For extensions in ISG50-2 (Remote Office), they need to dial 48XXXX to reach extensions in ISG50-1 (Main Office).
LCR for ISG50-1 (Main Office) LCR for ISG50-2 (Remote Office)
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