The DNS concept dates from the 1960s, also known as the ARPANET era. At that time, scientists engaged in the ARPANET project were trying to find a way of memorizing names instead of IP addresses. At the beginning of the 1980s, in the form of Requests for Comments (RFC) documents, the first specification documents were published about the DNS.
The nature of a DNS is that it has a tree structure (hierarchical), where each branch represents the root zone and each leaf has zero or more resource records. Each zone can represent a root domain or multiple domains and sub-domains. A domain name consists of one or more parts, known as labels, and are separated by a period (for example, packtpub.com). DNS is maintained by a database that uses distributed clients/server architecture where network hosts represent the servers' names. The following steps illustrate how...
