14. Interpret Sequence Diagram That Includes API Calls 200-901 Practice Questions (Page 5)

Questions 21–25

1. 21foundation · easy

   What does a thin rectangle overlaid on a lifeline in a UML sequence diagram represent?

   • AThe period during which the participant is active or processing
   • BThe message that is being sent to the participant
   • CThe time when the participant is created or destroyed
   • DThe combined fragment that contains the participant's logic
   Reveal Solution Discussion Select an answer first
2. 22application · easy

   A sequence diagram shows the following messages: 1) Client sends GET /auth/token to Auth Service, 2) Auth Service returns token to Client, 3) Client sends GET /devices to Device API, 4) Device API returns device list to Client. What is the correct chronological order?

   • AThe Auth Service sends the token after the Device API returns the device list.
   • BThe client obtains a token before requesting the device list.
   • CThe client requests the device list before obtaining a token.
   • DThe Device API returns the device list before the client sends the token request.
   Reveal Solution Discussion Select an answer first
4. 23foundation · easy

   When interpreting a sequence diagram for an API call, what does the arrangement of lifelines from left to right indicate?

   • AThe relative processing speed of each component
   • BThe physical network topology of the components
   • CThe security level of each component
   • DThe order in which participants are involved in the interaction
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5. 24foundation · easy

   Which sequence diagram notation best represents an asynchronous API call?

   • AA half-open arrow (stick arrowhead) from the caller to the API, with no immediate return arrow
   • BA message arrow with a filled diamond at the source end
   • CA combined fragment labeled 'alt' with two message alternatives
   • DA solid arrow from the caller to the API followed by a dashed return arrow
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6. 25application · medium

   A network automation script calls a REST API to retrieve device configurations. The sequence diagram shows a loop fragment around the GET /devices message, followed by a GET /devices/{id}/config message inside the loop. What does this indicate about the API call flow?

   • AThe script repeatedly fetches the entire device list until a configuration is returned.
   • BThe script retrieves the device list once, then iterates through each device to fetch its configuration.
   • CThe script fetches the device list only if a configuration is missing.
   • DThe script fetches the device list and configuration in parallel for all devices.
   Reveal Solution Discussion Select an answer first