Understanding Domain Name System (DNS) can greatly enhance your online experience and help you troubleshoot network issues more effectively. DNS acts like a phonebook for the internet, translating human-readable domain names into IP addresses that computers use to communicate with each other.

How DNS Works

When you type a website address (domain name) into your browser, several steps occur behind the scenes to connect you to the correct server:

  1. Your device's resolver is contacted. This could be Internetport's DNS servers or another service configured on your network.
  2. The resolver queries a set of root servers, which are like the main directories in a phonebook.
  3. The root server directs the resolver to a Top-Level Domain (TLD) server, such as .com, .org, or .net.
  4. The TLD server then points the resolver to an authoritative nameserver for the specific domain you're trying to reach.
  5. Finally, the authoritative nameserver provides the IP address of the website's server, allowing your browser to establish a connection.

DNS Components Explained

Resolvers

A resolver is software on your device that handles DNS queries. It caches responses to speed up future requests for the same domain name.

Root Servers

There are 13 sets of root servers worldwide, each identified by a letter from A to M. They don't store information about specific domains but direct resolvers to the appropriate TLD server.

TLDs (Top-Level Domains)

TLDs are the extensions at the end of domain names, such as .com, .org, or country-specific codes like .se for Sweden. Each TLD has its own set of authoritative servers.

Authoritative Nameservers

These are the final stop in the DNS lookup process. They store and provide information about specific domain names, including their IP addresses.

DNS Record Types

Different types of DNS records serve various purposes:

  • A (Address): Maps a domain name to an IPv4 address.
  • AAAA (IPv6 Address): Maps a domain name to an IPv6 address.
  • CNAME (Canonical Name): Aliases one domain name to another.
  • MX (Mail Exchange): Specifies mail servers for the domain.
  • NS (Name Server): Delegates a DNS zone to use the given authoritative nameservers.

TTL (Time-to-Live)

TTL is a value set in each DNS record that indicates how long a resolver should cache the information before checking with the authoritative server for updates. A shorter TTL means more frequent updates but can slow down performance slightly.

Troubleshooting

If you encounter issues accessing websites, DNS problems might be to blame:

  • Check your DNS settings: Ensure that your device is using the correct DNS servers. Internetport's primary and secondary DNS servers are 193.168.0.254 and 193.168.0.253, respectively.
  • Flush your DNS cache: This can resolve issues with outdated cached records. On Windows, use the command ipconfig /flushdns. On macOS or Linux, use sudo killall -HUP mDNSResponder.
  • Contact Internetport support: If problems persist, reach out to our customer service for further assistance.