DNS & HTTP · Beginner – Online Test

Question 1 DNS Beginner Practice

What does DNS do?

Encrypts web traffic Routes packets between networks Translates host names such as learnfrenzy.com into IP addresses (and other records), using a distributed hierarchy of servers Assigns IP addresses to hosts

Question 2 DNS Beginner Practice

Which transport and port do ordinary DNS queries use?

UDP port 53 (falling back to TCP 53 for large responses and zone transfers) UDP port 67 TCP port 25 TCP port 80

Question 3 DNS Beginner Practice

Which DNS record type maps a name to an IPv6 address?

MX CNAME AAAA A

Question 4 HTTP Beginner Practice

What does HTTP status 404 mean?

Server error Not Found – the server has no resource at that URL Unauthorised Moved permanently

Question 5 HTTP Beginner Practice One or more answers

Which HTTP methods are defined as idempotent (repeating them has the same effect as doing them once)?

PUT POST DELETE GET

Question 6 HTTP Beginner Practice

HTTP is stateless. How do websites keep you logged in?

DNS stores the session The server sets a cookie (often a session ID or token) that the browser sends back with every later request The IP address identifies the user HTTP remembers the TCP connection

Question 7 DHCP Beginner Practice

What is the order of DHCP messages when a laptop joins a network?

Getting an address

OfferDiscoverAcknowledgeRequest DiscoverOfferRequestAcknowledge RequestOfferDiscoverAcknowledge DiscoverRequestOfferAcknowledge

Question 8 Email Beginner Practice

How do SMTP, POP3 and IMAP divide the work of email?

IMAP sends, SMTP reads All three send mail SMTP sends and relays mail between servers; POP3 downloads (and usually deletes) it; IMAP keeps mail on the server and syncs folders across devices POP3 encrypts mail

Question 9 FTP Beginner Practice

Why is FTP said to send its control information "out of band"?

It uses UDP It has no commands Commands go over a separate control connection (port 21) while files travel on separate data connections (port 20 in active mode) It sends commands inside the file

Question 10 Architectures Beginner Practice

What is the key advantage of peer-to-peer file distribution (like BitTorrent) over a single server?

It is always more secure Self-scalability – each new peer also uploads, so total capacity grows with demand It needs no Internet Peers never leave

Question 11 HTTP Beginner Practice One or more answers

Which pairings are correct?

503 Service Unavailable 301 Moved Permanently 200 OK 304 Not Modified 403 Internal Server Error

Question 12 DNS Beginner Practice Answer computed

How many named root server identities (a.root-servers.net to m.root-servers.net) are there?

Your answer

Question 13 HTTP Beginner Practice Code executed

What does this print?

Python main.py

from urllib.parse import urlparse

u = urlparse('https://learnfrenzy.com:8443/technical-tests/cn?level=2#top')
print(u.scheme, u.hostname, u.port, u.path, u.query)

https learnfrenzy.com 8443 /technical-tests/cn level=2 https learnfrenzy.com 443 /technical-tests/cn level=2 http learnfrenzy.com 8443 /technical-tests level=2 https learnfrenzy.com:8443 None /technical-tests/cn level=2#top

Question 14 HTTP Beginner Practice

Which is a real difference between GET and POST?

GET cannot return data POST is encrypted, GET is not GET carries parameters in the URL and should not change server state; POST carries data in the request body and is used to submit or create POST cannot be used by forms

Question 15 Architectures Beginner Practice

How does a CDN speed up a website for users around the world?

It compresses the user's Internet link It caches content on servers close to users (often chosen via DNS or anycast), cutting RTT and offloading the origin It removes DNS lookups It upgrades HTTP to FTP

DNS & HTTP · Beginner

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