The internet's hidden directory: How DNS keeps the digital world connected

Domain Name System (DNS) is like the internet’s phonebook. It translates human-friendly domain names (e.g., www.upsc.gov.in) into IP addresses (e.g., 164.100.94.59) that computers use to identify each other on a network.

Without DNS, we would have to memorise long numeric IPs for every website.

How DNS works

• User enters URL in browser
• DNS Resolver checks if IP is cached locally; if not, queries start
• Root DNS Server directs to Top-Level Domain (TLD) Server (e.g., .in, .com)
• TLD Server points to Authoritative Name Server for that domain
• Authoritative Server returns IP address
• Browser connects to that IP → loads the website

Think of it as a hierarchical, distributed database maintained globally

Types of DNS records (important for tech security questions)

• A record → IPv4 address mapping
• AAAA record → IPv6 address mapping
• CNAME → Alias mapping
• MX → Mail server address
• TXT → Verification & security info (SPF, DKIM)

Analytical importance (Civil Services perspective)

Critical viewpoint

1. Centralisation risk – Although distributed, DNS root servers are few (Rs 13 logical root server clusters); potential geopolitical chokepoints.
2. Vulnerability to attacks – DNS spoofing can redirect traffic to malicious sites, threatening cybersecurity & citizen trust.
3. Dependency on US-based ICANN – Raises data sovereignty concerns for countries like India.
4. Censorship potential – Governments can block sites at DNS level, which may conflict with freedom of expression.
5. Lack of encryption – Traditional DNS queries are unencrypted; newer standards like DNS over HTTPS (DoH) and DNS over TLS (DoT) aim to fix this.

Relevance in India

• Digital India & BharatNet expansion → needs robust DNS infrastructure
• National Internet Exchange of India (NIXI) → manages .in domain
• CERT-In & MeitY initiatives → secure DNS practices for government websites
• Push for local DNS root servers to improve speed, security & sovereignty