System Architecture Principles Questions

Core principles and patterns for designing and evaluating high level and system architectures for distributed and cloud based systems. Candidates should understand high availability and redundancy, fault tolerance and graceful degradation, and how to design stateless and stateful components. They should be able to explain scalability and capacity planning strategies including horizontal and vertical scaling, partitioning and sharding, load balancing, caching and replication, and the trade offs involved. The topic covers consistency models and the trade offs between consistency, availability and partition tolerance, performance and latency optimization, reliability and durability, security for data and access control, and cost efficiency. Candidates should be able to discuss fault domains and why critical components are replicated across availability zones and regions, as well as backup, recovery and disaster recovery approaches. Common architectural patterns such as monolithic and microservice architectures, layered design, event driven and message based systems, and command query responsibility segregation are relevant. Monitoring and observability practices including metrics, logging, distributed tracing and alerting are part of assessments, together with the ability to justify architecture decisions based on functional and nonfunctional requirements, constraints, expected load and operational complexity.