Distributed Computing Quiz

What is a key feature of distributed systems?

• Single processor

• Centralized control

• Shared memory

• Geographical separation

Answer explanation

A key feature of distributed systems is geographical separation, as they consist of multiple interconnected components located in different physical locations, allowing for scalability and fault tolerance.

Which algorithm is used for distributed mutual exclusion?

• Suzuki-Kasami’s Broadcast Algorithm

• Lamport’s Algorithm

• Ricart-Agrawala’s Algorithm

• Chandy-Misra-Haas Algorithm

Answer explanation

Ricart-Agrawala’s Algorithm is specifically designed for distributed mutual exclusion, allowing processes to request and grant access to critical sections in a decentralized manner, making it the correct choice.

What does the term 'logical time' refer to in distributed systems?

• Physical clock synchronization

• A framework for logical clocks

• The time of day

• The time taken by a process

Answer explanation

'Logical time' in distributed systems refers to a framework for logical clocks, which helps to order events in a system without relying on synchronized physical clocks. This is crucial for consistency in distributed processes.

Which of the following is NOT a characteristic of cloud computing?

• Scalability

• High cost

• Load balancing

• Elasticity

Answer explanation

High cost is NOT a characteristic of cloud computing, as it typically offers cost efficiency through pay-as-you-go models. In contrast, scalability, load balancing, and elasticity are key features that enhance resource management.

What is the main purpose of message passing in distributed systems?

• To communicate between processes

• To manage resources

• To synchronize clocks

• To share memory

Answer explanation

The main purpose of message passing in distributed systems is to communicate between processes. It allows different processes, potentially on different machines, to exchange data and coordinate their actions effectively.

Which of the following is a model of communication in distributed systems?

• Centralized

• FIFO

• LIFO

• Synchronous only

Answer explanation

FIFO (First In, First Out) is a model of communication in distributed systems that ensures messages are processed in the order they are sent, making it suitable for maintaining consistency in message delivery.

What is the main challenge in designing distributed systems?

• Limited scalability

• Heterogeneity

• Single point of failure

• High latency

Answer explanation

Heterogeneity is the main challenge in distributed systems as it involves integrating diverse hardware, software, and network components, which can complicate communication and coordination, making system design more complex.

Which of the following is a property of causal ordering in message delivery?

• Messages must be delivered in the order they were sent

• Messages are delivered in any order

• Messages are always delivered immediately

• Messages can be dropped

Answer explanation

Causal ordering ensures that messages are delivered in the exact sequence they were sent. This means that if one message is sent before another, the first must be received before the second, making 'Messages must be delivered in the order they were sent' the correct choice.

What is the primary purpose of rollback recovery protocols in distributed systems?

• To increase the number of processes

• To reduce message transmission time

• To restore the system to a consistent state after a failure

• To enhance system performance

Answer explanation

The primary purpose of rollback recovery protocols in distributed systems is to restore the system to a consistent state after a failure, ensuring data integrity and continuity of operations.

What is a consistent global checkpoint?

• A checkpoint that can be taken at any time

• A global state that may occur during failure-free execution

• A checkpoint that is always outdated

• A checkpoint that does not involve any processes

Answer explanation

A consistent global checkpoint represents a global state that can be reached during normal execution without failures, ensuring that all processes are in a coherent state. This is why the correct answer is 'A global state that may occur during failure-free execution'.