11.02 How Data Moves On The Internet Packets Ip Dns Protocols - Quiz

Check your understanding

1. Which record types map a hostname to an IPv4 or IPv6 address?

   • A and AAAA { data-correct }
   • CNAME and TXT
   • MX and SRV
   • NS and SOA

2. Which protocol and default port does HTTPS use?

   • HTTP over TCP, port 80
   • HTTP over UDP, port 80
   • HTTP over TLS on TCP, port 443 { data-correct }
   • TLS over UDP, port 443

3. Which is true about TCP vs UDP?

   • UDP guarantees delivery and ordering; TCP does not
   • TCP establishes a connection and guarantees ordered delivery; UDP does not { data-correct }
   • Both TCP and UDP use handshakes
   • Both TCP and UDP retransmit lost packets by default

4. What does TLS primarily provide? (choose the best set)

   • Confidentiality, integrity, authentication { data-correct }
   • Compression, routing, congestion control
   • Name resolution, caching, negative responses
   • Load balancing, multiplexing, prioritisation

5. Place these in order for a first HTTPS request with a cold DNS cache:

   • HTTP request, TCP handshake, TLS handshake, DNS resolution
   • DNS resolution, TCP handshake, TLS handshake, HTTP request { data-correct }
   • TLS handshake, DNS resolution, HTTP request, TCP handshake
   • TCP handshake, DNS resolution, HTTP request, TLS handshake

6. Which of the following commonly use STARTTLS to upgrade a plaintext connection?

   • SMTP submission, IMAP, POP3 { data-correct }
   • DNS, HTTP, FTP
   • SSH, SFTP, SCP
   • TLS 1.3, HTTP/2, QUIC

7. When would DNS use TCP instead of UDP? (choose two)

   • For large responses that don’t fit in a single UDP packet { data-correct }
   • For zone transfers between DNS servers { data-correct }
   • For typical small A/AAAA record lookups
   • For better latency on lossy links

8. Match protocol to default port:

   • DNS → 53 { data-correct }
   • SMTP → 25 { data-correct }
   • IMAP (unencrypted) → 143 { data-correct }
   • HTTPS → 443 { data-correct }

9. What does SNI (Server Name Indication) in TLS allow?

   • A client to specify the domain it’s requesting during the TLS handshake { data-correct }
   • DNS to tell the browser which IP to use
   • The server to force the client to use HTTP/2
   • A client to bypass certificate validation

10. Which developer tool would you use to view the certificate chain and TLS version for a site?

    • Browser Security tab / padlock details { data-correct }
    • Browser Console tab
    • traceroute / tracert
    • ping