When We talk about the Object identification in QTP. the object identification is done on Windows handle. it means, in object repository we store the mapping of the actual windows handle of the object and during executing the test this mapping is used to identify the same element and perform desired action on it.
When QTP uses the recorded description to identify an object, it searches for an object that matches with property values in the description. In most cases, this description is the simplest way to identify the object and unless the main properties of the object change, this method will work.
Smart Identification is used by QTP, whenever it is unable to identify any object during run time. While identifying an object, QTP tries to match the mandatory properties first, if it couldn’t find the object, then it adds assertive properties one by one to identify the object correctly. This operation is done by smart identifier and it is displayed in the results section along with one warning message. It’s generally used to identify Web elements only.
The Smart Identification mechanism uses two types of properties:
Base filter properties—Properties of a particular test object class, those whose values cannot be changed without changing the essence of the original object
Optional filter properties—Other properties that can help to identify test objects of a particular class as they are unlikely to change on a regular basis