Custom Template DECT

[Mateusz_Tomaszewski]

Hello,
I am writing regarding custom template for DECT devices on PBX. There are several custom tamplats created on the PBX, but we are unable to assign any of them to the newly added W70B base.
Hence my question, how is it in version 18 adding custom tamplates to DECT devices?
I don't see such an option to select.

When adding a desk phone, we see all Custom Tamplates to choose from.

 

[JohnS_3CX]

Hi Mateusz,

There was never an option for DECT custom templates.

We only had the option for custom templates on IP phones, or rather anything appearing under this category (DECT not included).




We do not provide any method of doing so and it would probably cause issues in your system going forward (and can even break updates) so we strongly recommend against it.

 

[ltri37]

This is unfortunate, default 3CX FXS templates (which has the same concept as DECT templates) contain configuration issues that will lead to service outages.

For Grandstream FXS Gateways (GXW):

Disable voice prompt (P253) is not enabled, meaning every FXS user can put the entire FXS Gateway out of service with a few simple prompts (*** for the voice prompt, 001 for the Network mode setting, hit 9 until you get "PPPoE mode", exit with # and enter menu 099 and hit 9 to reboot the gateway into the new PPPoE configuration, that's a sure way to disconnect the Grandstream from the network requiring administrator intervention). By combining multiple features, the device can be fully factory reset from the FXS port (get the mac address by calling *** for the voice prompt and 010 for the mac address reading feature, then use the factory reset from FXS procedure - *** then 099, which - as a security measure - asks for the mac address that you just got).

<!-- Disable voice prompt. 0 - No, 1 - Yes. -->
<!-- Number: 0,1 -->
<!-- Mandatory -->
<!-- P253=0 -->

Above: 3CX template does not enable the most important setting of them all: Disabled voice prompt; causing FXS users in hotel rooms to be able to reboot/factory reset/disconnect from network entire FXS gateways.




At least when manually enabling this option ("Disable voice prompt") it is currently not rolled back by 3CX, which we can't say about Call Features (P191): 3CX force enables Call Features, which means that a user can insert all kinds of configurations and set features that are not acceptable for hotel rooms: call fowarding, dnd modes, caller id block. We can't have those features enabled in hotel rooms when hotel guests are untrusted and their FXS user configuration will affect the next guest.

Often this is not the results of sophisticated attackers (able to read Grandstream manuals), but simple someone trying to a few star codes randomly or by mistake, which then leads to issue for the current and the subsequent hotel guests in this room.

<!-- Enable Call Features. 0 - No, 1 - Yes, 2 - Enable All -->
<P191>1</P191>

Above: 3CX template force enabling Call Features.




The "Reply to ICMP" feature is force disabled by 3CX provisioning, meaning we can't even put those FXS Gateway in our monitoring system, because it will not respond to ping.

<!-- # Reply to ICMP. 0 -No, 1 -Yes -->
<!-- # Number: 0, 1 -->
<!-- # Mandatory -->
<P189>0</P189>

So, I can't say that I'm a fan of current FXS templates or the fact that there is not supported way to edit them.