Hello,
This is CUCM and not CME?
I was helping somebody yesterday with a similar issue, have a look at https://supportforums.cisco.com/message/3268643#3268643
To hide the calling name and/or number between IP phones you need a translation pattern to remove the caller details.
If your case the room phone calling search space needs to have a partition that can ring the reception and a partition the contains a translation pattern but NOT the room phones
the translation pattern looks something like:-
Pattern [78]xxxx
Calling search space, must include the room phone DN partition
Set all Calling Line ID Presentation, Calling Name Presentation, Connected Line ID Presentation, Connected Name Presentation to 'Restricted'
That should meet your needs, let me know if you need further assistance.
Craig
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