DNS and IP Addresses

When you visit a website like codeharborhub.github.io, your browser doesn’t actually understand the name, it only understands numbers. These numbers are called IP addresses, and the system that translates human-friendly names into them is called the Domain Name System (DNS).

What Is an IP Address?

An IP (Internet Protocol) address is a unique identifier assigned to every device connected to the Internet. It’s like a postal address for computers, it tells other systems where to send or receive data.

Two Common Versions:

Version	Format	Example	Usage
IPv4	32-bit (4 numbers separated by dots)	192.168.1.1	Most widely used, limited supply
IPv6	128-bit (hexadecimal separated by colons)	2400:cb00:2048:1::c629:d7a2	Modern, supports billions of devices

What Is DNS?

The Domain Name System (DNS) is often described as the phonebook of the Internet. It translates easy-to-remember domain names (like google.com) into machine-readable IP addresses (like 142.250.190.78).

Without DNS, you’d have to memorize long strings of numbers just to visit your favorite websites.

How DNS Works — Step by Step

Let’s walk through what happens when you type https://codeharborhub.github.io into your browser:

Each lookup happens in milliseconds — that’s the magic of the Internet’s infrastructure.

DNS Components Explained

Component	Description
DNS Resolver	The first point of contact — usually operated by your ISP or a public service (like Google DNS 8.8.8.8).
Root Servers	The highest level in DNS — directs the query to the correct top-level domain (like .com, .org, .io).
TLD Servers	Handle requests for specific top-level domains.
Authoritative Name Servers	Contain the final IP record for the domain.

Types of DNS Records

Record Type	Purpose	Example
A	Maps a domain to an IPv4 address	example.com → 93.184.216.34
AAAA	Maps a domain to an IPv6 address	example.com → 2606:2800:220:1:248:1893:25c8:1946
CNAME	Alias to another domain	www.example.com → example.com
MX	Mail server record	example.com → mail.example.com
TXT	Stores text info (often for verification)	v=spf1 include:_spf.google.com ~all

Real-World Analogy

Think of DNS like asking for directions:

• You know the name of a restaurant (domain name).
• You ask a directory service (DNS) for its address.
• You drive to that location (IP address).

Without DNS, you’d have to remember every single street address (IP) manually.

Fun Fact

The first DNS system was invented in 1983 by Paul Mockapetris, replacing a single centralized text file (hosts.txt) that originally stored all Internet addresses!

DNS and Security

Since DNS is critical to Internet functionality, it’s also a target for attacks like:

• DNS Spoofing (Cache Poisoning): Fake responses redirect users to malicious sites.
• DNS Hijacking: Attackers modify DNS settings to steal traffic.

To mitigate this, technologies like DNSSEC (Domain Name System Security Extensions) ensure authenticity and integrity of DNS responses.

Quick Demo

Live Editor

function DnsLookupDemo() {
  const [ip, setIp] = React.useState("");
  const lookup = () => setIp("185.199.108.153");
  return (
    <div style={{ textAlign: "center" }}>
      <h3>DNS Lookup Simulation</h3>
      <p>Domain: codeharborhub.github.io</p>
      <button onClick={lookup}>Resolve Domain</button>
      {ip && <p> IP Address: {ip}</p>}
    </div>
  );
}

Result

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Key Takeaways

• IP addresses identify devices; DNS translates names to addresses.
• The DNS process involves resolvers, root servers, TLD servers, and authoritative servers.
• Common record types: A, AAAA, CNAME, MX, TXT.
• DNSSEC helps secure DNS lookups from tampering.
• Every website you visit goes through a DNS lookup first — it’s the Internet’s invisible phonebook.

“Every website starts with a name, but it’s DNS that tells your browser where that name truly lives.”