Question 1hardmulti select
Full question →hardmulti selectObjective-mapped
Which two statements accurately describe UDP compared with TCP?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
UDP is connectionless.
This is correct because UDP does not establish a connection before sending data.
B
Distractor review
UDP always guarantees delivery and sequencing.
This is wrong because guaranteed delivery and sequencing are TCP features, not UDP features.
C
Best answer
UDP has lower overhead because it uses a simpler header and no session establishment.
This is correct because UDP uses a simpler header and avoids connection-establishment overhead.
D
Distractor review
UDP requires a three-way handshake before application data can be sent.
This is wrong because the three-way handshake belongs to TCP.
E
Distractor review
UDP cannot be used by DNS.
This is wrong because DNS commonly uses UDP for standard queries and responses.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting answers that incorrectly attribute TCP features to UDP, such as guaranteed delivery, sequencing, or the three-way handshake. Candidates might mistakenly think UDP requires connection setup or that it cannot be used by services like DNS. This confusion arises because TCP and UDP both operate at the transport layer but serve different purposes. Remember, UDP is connectionless and does not guarantee delivery, while TCP is connection-oriented and reliable. Misunderstanding these differences can lead to incorrect choices on the exam.
Technical deep dive
How to think about this question
UDP (User Datagram Protocol) is a transport layer protocol that provides a connectionless communication model. Unlike TCP, UDP does not establish a session or connection before sending data, which means it sends packets called datagrams without prior handshaking. This design results in lower latency and overhead, making UDP suitable for applications where speed is critical and occasional data loss is acceptable, such as DNS queries, streaming, or VoIP. The fundamental rule distinguishing UDP from TCP is that UDP does not guarantee delivery, ordering, or error recovery. TCP, by contrast, uses a three-way handshake to establish a connection and implements mechanisms for reliable delivery, sequencing, and flow control. UDP’s simpler header and lack of session establishment reduce protocol overhead, which is why UDP is considered connectionless and lightweight in Cisco networking contexts. A common exam trap is confusing UDP’s connectionless nature with unreliability or assuming UDP cannot be used for important services. In practice, UDP is widely used for DNS and other critical applications because its speed and simplicity outweigh the lack of built-in reliability. Cisco devices and protocols often leverage UDP for efficiency, so understanding this balance is crucial for CCNA exam success and real-world network design.
KKey Concepts to Remember
- UDP is a connectionless protocol that sends data without establishing a session or performing a handshake before transmission.
- UDP uses a simpler header than TCP, which reduces protocol overhead and improves transmission speed in Cisco networks.
- TCP guarantees delivery, sequencing, and error recovery by establishing a connection through a three-way handshake before data transfer.
- UDP does not guarantee delivery or sequencing, making it suitable for applications prioritizing speed over reliability.
- DNS commonly uses UDP for standard queries because UDP’s low overhead supports fast request and response cycles.
- The absence of connection establishment in UDP means it does not perform flow control or retransmission of lost packets.
- Cisco devices leverage UDP for services that require minimal delay and can tolerate occasional data loss, such as streaming and VoIP.
- Confusing UDP’s connectionless nature with unreliability can lead to exam mistakes; understanding the protocol’s design purpose is essential.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
UDP is a connectionless protocol that sends data without establishing a session or performing a handshake before transmission.
What is the correct answer to this question?
The correct answer is: UDP is connectionless. — UDP is designed for simplicity and speed rather than built-in reliability. In plain terms, it sends data without creating a formal conversation first. That is why it is called connectionless. Because it does not perform the same reliability features as TCP, its header is smaller and the protocol adds less overhead. This makes UDP a good fit for applications that care more about speed or low delay than guaranteed delivery at the transport layer. UDP does not perform a three-way handshake, and it does not guarantee delivery. It is also used by many real services, including DNS in common query scenarios.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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