Interview Q&A / Computer Networks
Computer Networks interview questions
What happens when you open a website, TCP vs UDP, DNS and HTTP.
Prefer rapid revision? Practise Computer Networks short interview answers →
- What happens when you type a URL in the browser and press Enter?
The browser finds the server's IP address with DNS, opens a TCP connection, sets up TLS for HTTPS, sends an HTTP request, gets a response and then parses and renders the HTML, CSS and JavaScript into the page you see.
BeginnerIn-depth3 min read - What are the common DNS record types: A, AAAA, CNAME, MX, TXT and NS?
A maps a name to an IPv4 address, AAAA to an IPv6 address, CNAME makes one name an alias of another, MX names the mail servers, TXT holds free text such as verification and SPF data, and NS lists the authoritative name servers for the domain.
BeginnerQuick answer1 min read - What is DNS TTL, and why do DNS changes seem to take time to "propagate"?
TTL is how many seconds resolvers may cache a record. When you change a record, resolvers that cached the old one keep serving it until its TTL expires, so different users see the change at different times.
BeginnerQuick answer1 min read