Direction: Read the questions carefully. Write the letter that corresponds to the correct answer. What is the primary characteristic of "tight coupling" in software integration?

• Components are independent and communicate via a message broker.

• Two components are highly dependent on each other, with detailed knowledge of each other's interface and location.

• A single, giant application handles all tasks.

• Communication follows a "fire-and-forget" principle.

What is a major drawback of a tightly coupled system, described as "brittleness"?

• The system is flexible and can easily add new services.

• The system performs faster because services communicate directly.

• If one service fails, the entire chain of services that depend on it also fails.

• It only requires scaling the specific service that is a bottleneck.

What is the core idea behind asynchronous messaging?

• A service makes a call and must wait for a direct response before continuing its own work.

• A service announces an event and can immediately respond to the user without waiting for other services to complete their tasks.

• All services in a system are combined into a single monolithic application.

• Services have detailed knowledge of each other's inner workings to ensure proper communication.

How is "loose coupling" defined?

• Two components are highly dependent on each other, similar to two people holding hands.

• Components are independent and interact through a well-defined interface without knowledge of each other's existence or internal workings.

• A system where a change in one service often requires changes in all the services that call it.

• A system where an order service makes a direct HTTP call to a payment service and waits for a response.

In the restaurant kitchen analogy, what does the central ticket queue represent?

• The Producer/Publisher

• The Consumer/Subscriber

• The Message Broker

• The "order placed" message

What is the correct pip command to install the Paho-MQTT library?

• pip install mqtt

• pip get paho-mqtt

• pip install paho-mqtt

• python -m install paho

The Paho-MQTT library's mental model is built around which two key concepts?

• The Broker and the Topic

• The Client Object and Callbacks

• Publishers and Subscribers

• loop_start() and loop_stop()

In a Paho-MQTT subscriber script, what is the primary purpose of the on_message callback function?

• To check if the connection to the broker was successful.

• To run when a message has been successfully published to the broker.

• To start the network loop in a background thread.

• To run when a message has been received from the broker on a subscribed topic.

What is the function of the client.loop_start() method?

• It starts a while True: loop to keep the main script alive.

• It starts a new background thread to automatically handle all network traffic.

• It publishes a message in a continuous loop.

• It immediately stops the network connection.

What happens if a second client connects to a broker with the same Client ID as an existing client?

• Both clients will receive all messages.

• The second client's connection will be rejected.

• The first client gets kicked off the broker.

• The broker will automatically assign a new unique ID to the second client.