Definīcija: A component of Exchange transport that processes all incoming messages and determines what to do with the messages based on information about the intended recipients. In Exchange Server 2007, the Edge Transport server uses the categorizer to route the message to the appropriate destination. The Hub Transport server uses the categorizer to expand distribution lists and identify alternate recipients and forwarding addresses. After the categorizer retrieves full information about recipients, it uses that information to apply policies, route the message, and perform content conversion.