DNS
What is the Domain Name Service (DNS) and what does it do for email services?
The DNS is a fundamental Internet service that converts human-readable names (domains, web addresses, computer names) into IP addresses. DNS is hierarchically organized, whereby one area (domain) can have other subordinate domains. Within a domain, an organization has control over all entries.
The most important entry for e-mail is the MX record, which provides the responsible mail server for a domain.
The Domain Name System is hierarchically organized and distributed worldwide. Each operator of DNS servers manages parts of the namespace, the “zones” or “domains”.
DNS can also be used to retrieve other information, such as spam detection using a DNS blacklist.
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