Concepts of TCP/IP and the Link Layer GCIA Practice Questions (Page 7)

Questions 31–35

1. 31expert · hard

   A packet capture shows an IPv4 packet with the Identification field set to 0x1A2B, the Flags field set to 0x2 (Don't Fragment), and the Fragment Offset set to 0. The packet's total length is 1500 bytes, and the MTU of the outgoing interface is 1500. What will happen when this packet is forwarded to a network with an MTU of 1400?

   • AThe router will forward the packet without modification because the MTU is only 100 bytes smaller.
   • BThe router will drop the packet and send an ICMP Fragmentation Needed message.
   • CThe router will clear the DF bit and fragment the packet.
   • DThe router will fragment the packet into two fragments.
   Reveal Solution Discussion Select an answer first
2. 32foundation · easy

   Which TCP header field is used to control the amount of data a sender can transmit before waiting for an acknowledgment?

   • AWindow Size
   • BChecksum
   • CData Offset
   • DSequence Number
   Reveal Solution Discussion Select an answer first
4. 33expert · hard

   A security analyst is examining a TCP session and sees a packet with the SYN and FIN flags set, along with an acknowledgment number that does not correspond to any prior sequence number. Which of the following is the most likely explanation?

   • AThe packet is part of a TCP scan technique designed to evade simple firewall rules.
   • BThe packet is a retransmission of a lost SYN packet.
   • CThe packet is a normal part of the TCP three-way handshake.
   • DThe packet is a keep-alive probe sent by the server.
   Reveal Solution Discussion Select an answer first
5. 34foundation · easy

   What is the purpose of the Address Resolution Protocol (ARP)?

   • ATo translate domain names to IP addresses
   • BTo assign IP addresses to hosts dynamically
   • CTo resolve IP addresses to MAC addresses on a local network
   • DTo route packets between different networks
   Reveal Solution Discussion Select an answer first
6. 35foundation · easy

   What happens when an IPv4 packet exceeds the MTU of a network link?

   • AThe packet is automatically compressed to fit the MTU.
   • BThe packet is sent as is, and the receiver discards the excess data.
   • CThe packet is fragmented into smaller pieces, each with its own IP header.
   • DThe packet is dropped and an ICMP error is always sent to the source.
   Reveal Solution Discussion Select an answer first