sentences:  Once a log file has been signed using ARRL's "TrustedQSL" (or equivalent) program, it is uploaded to the ARRL server and entered in the database.Log records in the LoTW database are automatically compared so that when a contact at a particular time, operating mode, and frequency band is claimed by both participating amateurs (who both must have submitted their logs), a "QSL" (confirmation) is declared for a later award claim, e.g., for contacts with all U.S. states or 100 different countries.The matching process is blind, meaning that none of the two stations can see pending confirmations for him before he uploads a matching record.