Logic of customer interface program

Hi,

How the Customer Interface program checks the duplicacy of Customer which is already exists in AR ?

If there is customer already exists in AR e.g Customer Name : 'ABCPQR' and again from Source system a customer is sent with name ABC PQR, then , is this customer treated as same customer or different customer. The difference is of Space in both customer.

Take another example where customer which is exists in AR is 'ABC of PQR' and from Source system a customer is sent with name  is 'ABC Of PQR'. whether these customer will be treated as same customer or different customer by interface progaram ?