CSI Message Queuing & Event-Driven Architecture 3

Question 1

Which messaging protocol is commonly used for lightweight, low-bandwidth IoT device integration and operates on a publish/subscribe model over TCP?

Accepted Answer

MQTT

Answer

AMQP

Answer

STOMP

Answer

SOAP/JMS

Question 2

In event-driven architecture, what is an 'event schema registry' primarily used for?

Accepted Answer

Storing and enforcing versioned schemas to ensure producers and consumers agree on event structure

Answer

Authenticating producers before they can publish events

Answer

Load balancing events across multiple broker nodes

Answer

Archiving old events after their retention period expires

Question 3

What is 'back-pressure' in a message-driven integration pipeline?

Accepted Answer

A flow-control mechanism where a slow consumer signals the producer to slow down or pause to avoid being overwhelmed

Answer

Network latency introduced by encryption overhead

Answer

Duplicate message detection at the broker level

Answer

The process of reprocessing failed events from a dead letter queue

Question 4

When designing a message-based integration, what does 'message TTL' (Time-To-Live) control?

Accepted Answer

How long a message remains in the queue before being discarded or moved to a dead letter queue if not consumed

Answer

The encryption key rotation interval for message payloads

Answer

The maximum size of a message payload in kilobytes

Answer

The frequency at which consumers poll the broker for new messages

Question 5

Which pattern is best suited for integrating a legacy system that cannot be modified to publish events directly into a modern event-driven architecture?

Accepted Answer

Change Data Capture (CDC) from the legacy system's database transaction log

Answer

Event streaming via native API hooks

Answer

Direct consumer polling of the legacy application's in-memory cache

Answer

Schema migration to a canonical event format within the legacy system

Question 6

A system integrator is designing a workflow where multiple independent services each process the same order event. Which pattern best supports this requirement?

Accepted Answer

Choreography-based event fan-out where each service subscribes to the same topic

Answer

Competing consumers with a single queue

Answer

Synchronous request/reply chain through a gateway

Answer

Point-to-point routing with a dedicated queue per service pair

Question 7

What is the primary difference between message queuing and event streaming platforms like Kafka?

Accepted Answer

Streaming platforms retain messages as an ordered, replayable log, while traditional queues typically delete messages after consumption

Answer

Message queues support pub/sub while streaming platforms only support point-to-point

Answer

Message queues provide higher throughput than streaming platforms

Answer

Streaming platforms require synchronous acknowledgment while queues support asynchronous delivery