Assuming that a Meridian digital telephone has a class of service (CLS) which allows the display to work, this will be ADD or TDD or DDD but not NDD, (for an explanation of these terms please click on the link at the base of the answer) then several options are available on how information is displayed on extensions, the CLS options are:
Always start with:
CNDA (called name display allowed), this allows the calling extensions name to be displayed on the called set.
CNDD prevents the above.
DNDA (dialled name display allowed) this can only be set if CNDA is also set, in this instance if a call is diverted the name displayed will be the originally dialled DN's name and not the callers.
DNDD prevents the above but if CNDA was still set then the callers name would display on diverted calls.
Even with the above settings allowing called TN's to display information it is possible to programme up a TN to withhold information as below:
DDGA (DN display on other set allowed) with this set the callers DN is allowed to be displayed on the called extensions display however if DDGD is set then the callers DN will not display.
NAMA (name display on other set allowed) this allows the callers name to be displayed on the receiving extensions display, but NAMD will prevent this.
How do I set the display on my Meridian digital extension to work? for information on allowing the display feature on a digital extension.