CSI System Design & Architecture 2

Question 1

In a distributed system, which consistency model allows reads to return stale data but guarantees that all replicas eventually converge to the same value?

Accepted Answer

Eventual consistency

Answer

Eventual consistency guarantees that all replicas will converge to the same value over time, but reads may temporarily return stale data.

Question 2

Which architectural pattern separates the data modification (command) path from the data retrieval (query) path into distinct models?

Accepted Answer

CQRS (Command Query Responsibility Segregation)

Answer

CQRS segregates commands (writes) and queries (reads) into separate models, optimizing each independently.

Question 3

A system integrator needs to connect a legacy COBOL mainframe to a modern REST API. Which integration approach is most appropriate?

Accepted Answer

API Gateway with adapter layer

Answer

An API Gateway with an adapter layer translates between legacy protocols and modern REST, enabling integration without full replacement.

Question 4

In microservices architecture, which pattern prevents cascading failures by stopping requests to a failing service after a threshold is exceeded?

Accepted Answer

Circuit Breaker Pattern

Answer

The Circuit Breaker pattern monitors failures and opens the circuit to stop requests to a failing service, preventing cascading failures.

Question 5

Which load balancing algorithm routes each new request to the server with the fewest active connections?

Accepted Answer

Least Connections

Answer

Least Connections routing directs traffic to the server currently handling the fewest active connections, balancing load dynamically.

(CSI) Certified System Integrator Practice Test

(CSI) Certified System Integrator Practice Test

CSI System Design & Architecture 2