Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
Why might a controller return interface information as a JSON array instead of a single JSON object?
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
Because an array is the appropriate structure for an ordered list of multiple interface entries.
This is correct because arrays are used to represent lists of repeated items.
B
Distractor review
Because a JSON object cannot contain fields.
This is wrong because JSON objects are made of fields.
C
Distractor review
Because arrays are used only for IPv6 interfaces.
This is wrong because arrays are a general data structure, not an IPv6-only feature.
D
Distractor review
Because arrays eliminate the need for API authentication.
This is wrong because data structure and access control are different concerns.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is believing that JSON objects cannot contain multiple fields or that arrays are only used for specific interface types like IPv6. This misunderstanding leads to incorrect assumptions about data representation in network automation. Candidates might also confuse data structure choices with unrelated concepts like API authentication, mistakenly thinking arrays affect security. The trap lies in conflating the purpose of JSON arrays as a data structure for multiple similar items with other unrelated networking or security concepts. Understanding that arrays simply represent ordered lists of items, such as multiple interfaces, is crucial to avoid this confusion.
Technical deep dive
How to think about this question
In network automation and programmability, JSON (JavaScript Object Notation) is a widely used data format for exchanging information between controllers and network devices. JSON supports two primary data structures: objects and arrays. A JSON object is an unordered collection of key-value pairs, ideal for representing a single entity with multiple attributes. Conversely, a JSON array is an ordered list of values, which can be objects themselves, making it suitable for representing multiple similar entities, such as interfaces on a router or switch. When a controller returns interface information, it often needs to provide details for multiple interfaces simultaneously. Using a JSON array allows the controller to encapsulate each interface as an individual JSON object within the array, preserving the order and grouping all interfaces together. This structure simplifies parsing and processing by automation tools, as each interface entry can be iterated over consistently. This approach aligns with common RESTful API design patterns used in Cisco's network programmability solutions, such as Cisco DNA Center and RESTCONF. A common exam trap is misunderstanding the role of JSON objects versus arrays in API responses. Some candidates might incorrectly assume that a single JSON object can represent multiple interfaces by nesting them, but this is less practical and breaks the semantic clarity of the data. Practically, network automation tools expect interface lists as arrays to handle multiple entries efficiently. Recognizing this distinction helps avoid confusion when interpreting API responses or designing automation scripts that interact with Cisco devices.
KKey Concepts to Remember
- A JSON array is the appropriate data structure to represent an ordered list of multiple similar network entities, such as interfaces or VLANs.
- Network controllers use JSON objects to represent single entities with multiple attributes, like one interface with its name, status, and IP address.
- Automation tools expect interface information as arrays to efficiently parse and iterate over multiple interface entries in API responses.
- JSON objects can contain multiple fields and nested objects, so the claim that they cannot contain fields is incorrect.
- Arrays are a general-purpose data structure in JSON and are not limited to any specific interface type like IPv6.
- Data structure choices in JSON responses are independent of API authentication or access control mechanisms.
- Understanding JSON data structures is essential for interpreting network programmability outputs and designing automation scripts.
- Using arrays for multiple interfaces aligns with RESTful API best practices commonly used in Cisco network automation platforms.
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?
A JSON array is the appropriate data structure to represent an ordered list of multiple similar network entities, such as interfaces or VLANs.
What is the correct answer to this question?
The correct answer is: Because an array is the appropriate structure for an ordered list of multiple interface entries. — A controller might return interface information as a JSON array because there are multiple interface records to present as a list. In practical terms, an array is the correct structure when the response includes several similar items, such as multiple interfaces, routes, or VLANs. Each element in the array can then be its own object with fields like name, status, or IP address. This is a data-structure recognition question. It is not about networking behavior directly, but about understanding how automation systems represent repeated information.
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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