Communication Exam
Study Guide: Questions, Answer Choices, Correct Answers, and Explanations
Green highlighted choices are the correct answers.
Question 1
What does a client do when it has UDP datagrams to send?
○ It sends to the server a segment with the SYN flag set to synchronize the conversation.
○ It queries the server to see if it is ready to receive data.
○ It sends a simplified three-way handshake to the server.
✓ It just sends the datagrams.
Explanation: UDP is connectionless, so it does not set up a session or use a three-way handshake
before sending data.
Question 2
Why does HTTP use TCP as the transport layer protocol?
○ because transmission errors can be tolerated easily
○ because HTTP is a best-effort protocol
✓ because HTTP requires reliable delivery
○ to ensure the fastest possible download speed
Explanation: HTTP relies on TCP because web data should arrive complete and in the correct order.
Question 3
Which three statements characterize UDP? (Choose three.)
○ UDP provides sophisticated flow control mechanisms.
✓ UDP is a low overhead protocol that does not provide sequencing or flow control mechanisms.
○ UDP provides connection-oriented, fast transport of data at Layer 3.
✓ UDP relies on application layer protocols for error detection.
○ UDP relies on IP for error detection and recovery.
CSIS330 Module 15 - Network Application Communication Exam Study Guide
, ✓ UDP provides basic connectionless transport layer functions.
Explanation: UDP is a simple Layer 4 protocol with low overhead. It is connectionless and does not
provide TCP-style sequencing or flow control.
Question 4
What kind of port must be requested from IANA in order to be used with a specific application?
○ dynamic port
✓ registered port
○ private port
○ source port
Explanation: Registered ports are assigned through IANA for specific applications or services.
Question 5
Which two fields are included in the TCP header but not in the UDP header? (Choose two.)
○ source port
✓ window
○ checksum
○ destination port
✓ sequence number
Explanation: TCP includes a window field and sequence numbers for reliable, ordered delivery.
Source port, destination port, and checksum are found in both TCP and UDP.
Question 6
What information is used by TCP to reassemble and reorder received segments?
○ port numbers
✓ sequence numbers
○ acknowledgment numbers
○ fragment numbers
Explanation: TCP uses sequence numbers to place received segments back into the correct order.
CSIS330 Module 15 - Network Application Communication Exam Study Guide