Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Which protocol is most directly responsible for keeping device clocks synchronized across a network?
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
NTP
This is correct because NTP is used to synchronize clocks across devices.
B
Distractor review
TFTP
This is wrong because TFTP is a lightweight file transfer protocol, not a clock synchronization protocol.
C
Distractor review
DHCP
This is wrong because DHCP assigns network settings to clients but does not primarily synchronize clocks.
D
Distractor review
CDP
This is wrong because CDP is a neighbor discovery protocol, not a time service.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting DHCP, TFTP, or CDP as the protocol responsible for clock synchronization. DHCP is often confused because it deals with network configuration, but it does not synchronize time. TFTP might seem relevant due to its role in transferring files like configurations, but it has no time-related function. CDP is a Cisco proprietary protocol for device discovery and neighbor information exchange, not for time services. Candidates must recognize that only NTP is designed specifically to keep device clocks synchronized across a network, which is critical for accurate logging and event correlation.
Technical deep dive
How to think about this question
Network Time Protocol (NTP) is the standard protocol used to synchronize the clocks of devices across a network. It operates by exchanging timestamped messages between a client and a time server, allowing devices to adjust their internal clocks to a common reference time. Accurate time synchronization is critical for network operations, including logging, security event correlation, and troubleshooting. Cisco devices support NTP as a key IP service to maintain consistent time across routers, switches, and other network elements. When a Cisco device is configured as an NTP client, it queries one or more NTP servers to obtain the current time. The device then applies algorithms to filter and select the best time source, adjusting its clock gradually to avoid abrupt changes. This process ensures that all devices in the network share a synchronized time base, which is essential for time-sensitive protocols and accurate event sequencing. Other protocols like DHCP, TFTP, and CDP serve different purposes and do not provide time synchronization services. A common exam trap is confusing NTP with other network protocols that serve different functions. For example, DHCP assigns IP addresses and network parameters but does not synchronize time. TFTP is used for simple file transfers, such as configuration backups, and CDP discovers neighboring Cisco devices. Understanding the distinct role of NTP in time synchronization helps avoid this confusion and ensures correct protocol identification in exam scenarios and real-world network management.
KKey Concepts to Remember
- NTP synchronizes device clocks by exchanging timestamped messages to maintain a consistent time reference across the network.
- Cisco devices use NTP clients to query reliable time servers and adjust their internal clocks gradually for accurate synchronization.
- Accurate time synchronization is essential for correlating syslog messages, security events, and troubleshooting records in network operations.
- DHCP assigns IP addresses and network configuration but does not provide any mechanism for clock synchronization.
- TFTP is a lightweight file transfer protocol used for transferring configuration files, not for time synchronization.
- CDP discovers directly connected Cisco devices and shares device information but does not synchronize clocks.
- NTP uses algorithms to select the best time source and prevent abrupt clock changes, ensuring network-wide time consistency.
- Misidentifying DHCP, TFTP, or CDP as time synchronization protocols is a common exam trap to avoid.
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?
NTP synchronizes device clocks by exchanging timestamped messages to maintain a consistent time reference across the network.
What is the correct answer to this question?
The correct answer is: NTP — The correct protocol is NTP. In plain language, NTP helps devices agree on the current time so that logs, authentication events, monitoring data, and troubleshooting records line up accurately. Without consistent time, a network team may see events from multiple devices but be unable to reconstruct the actual sequence correctly. This matters more than many people realize because accurate time underpins many operational workflows. Syslog messages, security events, and monitoring alerts become much easier to trust when devices are synchronized. DHCP, TFTP, and CDP are useful for other purposes, but they do not exist to align device clocks. NTP is the protocol specifically associated with time synchronization.
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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