DNS Query Simulator
Interactive Step-by-Step Walkthrough of DNS Resolution
DNS Query Simulator
Interactive step-by-step visualization of how DNS resolution works
Step 1: User Types Domain
User enters www.example.com in browser
The DNS resolution process begins when a user types a domain name into their browser or application. This triggers the operating system to initiate a DNS query.
Step 2: Browser Cache Check
Browser checks its local DNS cache
Step 3: OS Cache Check
Operating system checks its DNS cache
Step 4: Recursive Resolver Query
Query sent to configured DNS resolver
Step 5: Root Server Query
Resolver queries root nameservers
Step 6: TLD Server Query
Query sent to .com TLD servers
Step 7: Authoritative Query
Query sent to authoritative nameserver
Step 8: Response Chain
IP address returned through the chain
How It Works
DNS resolution follows a hierarchical process, starting from your device and working through multiple servers to find the authoritative answer. This distributed system ensures reliability and performance while translating human-readable domain names into IP addresses that computers use to communicate.
Understanding DNS Resolution
Key Concepts
- •Recursive Resolution: Your resolver does all the work for you
- •Hierarchical Structure: Root → TLD → Authoritative
- •Caching: Results are cached at multiple levels for speed
- •Authoritative Answer: The final source of truth
Server Types
- •Root Servers: 13 root servers worldwide (.)
- •TLD Servers: Handle top-level domains (.com, .org)
- •Authoritative NS: Contains the actual DNS records
- •Recursive Resolver: Your ISP or public resolver
Why This Matters
Understanding DNS resolution helps you troubleshoot connectivity issues, optimize website performance, and make informed decisions about DNS providers. The hierarchical structure ensures the internet remains scalable and resilient.
Performance
Caching at multiple levels reduces latency and improves user experience.
Reliability
Distributed system with redundancy ensures high availability.
Scalability
Hierarchical structure handles billions of domains efficiently.