DNS or Domain Name System is a system that lets users connect to websites by matching human-readable domain names with the unique IP address of the server where the website is stored.
What is DNS Used For?
An analogy of the DNS system would be a phonebook. Like a phonebook lists the names and surnames of people with phone numbers, the DNS lists domain names with their corresponding IP addresses.
When the user enters a domain name into their browser’s address bar, it looks up the IP address using DNS and connects the user to the server where that website is stored.
The domain name and its matching IP address in the DNS are called a DNS record. To reach a website, the first step is checking locally to see whether a DNS record is cached on a user’s machine. If it’s not, the query is sent to a local DNS server. Typically, this will be an ISP’s server and is often referred to as a resolving name server.
Here, it will check whether the records are cached. If not, the request is forwarded to a root name server to locate the DNS records. These servers are designated servers around the world that are responsible for storing DNS records and keeping the systems working smoothly.
Once the DNS records are located, a connection is opened to the website and it will be displayed on the user’s screen.
How does DNS Play a Role in Email?
Typically, email is sent from IP addresses. To this, the domain in an email address needs to be matched to an IP address to send the data with email. So, an email server uses DNS to match the address on the email address to its destination and deliver the email to the recipient.
When it comes to email, a business’s or organization’s sending reputation is the rating an ISP gives the business as a legitimate email sender. Therefore, every time the business sends an email, the ISP collects data that determines whether the business follows proper sending practices. It collates this into a score it uses to decide whether the email should be delivered or not.
Here, there are two types of email reputation, IP reputation, and domain reputation. IP reputation simply relates to the IP address of a business. Domain reputation, on the other hand, relates to the domain from where emails are sent. This means, if either part of the DNS record has a low reputation, it will impact a business’s email deliverability.