The Get Calling Name function attempts to retreive a name for the caller. The calling number is searched using the AD attributes of msRTCSIP-Line, mobile, and telephoneNumber. Of course, you may modify this search to suit your requirements.
There are several methods which can be utilized to perform this AD search:
For single-equal AD Lookups: Remember that the first valid AD lookup in a Translation Table returns all the AD attributes for that user. Any subsequent AD lookup within that same Translation Table will internally query the attributes returned in the first lookup--it will not make another request to the AD itself.
For double-equal AD Lookups: Avoid using this functionality liberally. Requests to the AD server are time-consuming. A heavy load of AD queries will negatively impact call processing time. You should only use this function if, within a Translation Table, you need to perform an AD lookup of two or more user's AD records.