Address mapping is the process by which a numeric Internet address is converted into an alphabetic IP address and vice versa.
This function is normally carried out by your ISP's domain name server. The settings within TCP/IP protocols normally allow you to select between 'Server assigned domain name server' and 'Specified domain name server'. The former setting is the default with most systems and, with most modern server technology, usually works well. The latter setting is sometimes seen as more reliable and efficient because it means that there is one less task to be carried out during the transmission of data.
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