Overview - Grandstream Networks UCM6100 Series Configuration

This document describes basic configuration to interconnect UCM6100 series and HT503. This is typically
applied to the scenario where users would like to add a HT503 not only as a remote extension but also as
an external PSTN trunk. It could be common that we prefer to grab a PSTN line from another PBX or a
PSTN line in a remote location, but we don't want to invest too much on a FXO gateway.
There are two ways to set up the UCM6100 series IP PBX with the HT503.

Method 1: Register the HT503 to the UCM6100 directly.

Method 2: Configure HT503 as a SIP peer trunk.
Warning:

When the UCM6100 series is interconnected with other HT503, it is NOT recommended to turn on
"Allow Guest Calls" under the UCM6100 web GUI->PBX->SIP Settings->General. Turning on this
option will allow unauthenticated calls coming through the UCM6100 series. Please be aware of
the security concerns when using this option.

When using the IVR in UCM6100 series, please be aware that if "Dial Trunk" option is turned on in
IVR settings, the call into the IVR will be able to dial outbound call using UCM6100's trunk. The
IVR's permission level will be used when making outbound calls in this case. Please select proper
permission level for the IVR to control the outbound calls allowed via "Dial Trunk".
Firmware Version 1.0.1.25

OVERVIEW

Configuring UCM6100 Series with HT503 Page 4 of 18