Question 1

What are the three primary cloud service models (IaaS, PaaS, SaaS), and how does a solutions architect decide which model fits a given workload?

Accepted Answer

The three primary cloud service models represent different levels of abstraction and management responsibility, and understanding them is fundamental to making sound architectural decisions.

Infrastructure as a Service provides the most control. The cloud provider manages physical hardware, networking, and virtualization, while you manage the operating system, middleware, runtime, and applications. Examples include Amazon EC2, Azure Virtual Machines, and Google Compute Engine. IaaS is the right choice when you need full control over the environment, have specialized OS or software requireme

Question 2

Explain the shared responsibility model in cloud computing and why it matters for solutions architects designing secure systems.

Accepted Answer

The shared responsibility model defines the division of security and management obligations between the cloud provider and the customer. It is one of the most important concepts a solutions architect must internalize because misunderstanding it leads to security gaps and compliance failures.

The cloud provider is responsible for security of the cloud. This includes the physical infrastructure such as data centers, hardware, networking equipment, and the hypervisor layer. Providers also handle global infrastructure availability, patching the underlying host operating systems, and ensuring th

Question 3

What is load balancing, what are the common types of load balancers, and why is it a fundamental component in system design?

Accepted Answer

Load balancing distributes incoming network traffic across multiple servers to ensure no single server becomes overwhelmed. It is a foundational system design component because it enables both scalability and high availability.

At its core, a load balancer sits between clients and a pool of backend servers. When a request arrives, the load balancer selects a server based on an algorithm and forwards the request. Common algorithms include round robin, which cycles through servers sequentially; least connections, which sends traffic to the server handling the fewest active requests; and weigh

Question 4

Explain the role of caching in system design. What are the common caching strategies, and where would you place caches in an architecture?

Accepted Answer

Caching stores frequently accessed data in a faster storage layer so that future requests can be served more quickly. It is one of the most effective techniques for improving system performance, reducing latency, and lowering the load on backend databases and services.

Caches can be placed at multiple layers of an architecture. At the edge, a Content Delivery Network caches static assets like images, CSS, and JavaScript at locations geographically close to users, reducing latency dramatically. At the application layer, an in-memory cache like Redis or Memcached stores computed results, data

Question 5

What is the difference between functional and non-functional requirements, and why must a solutions architect understand both?

Accepted Answer

Functional and non-functional requirements together define the complete picture of what a system must do and how well it must do it. A solutions architect must deeply understand both because they drive fundamentally different architectural decisions.

Functional requirements describe what the system should do. They define specific behaviors, features, and capabilities. Examples include allowing users to register with an email and password, processing credit card payments, generating monthly reports, and sending email notifications when an order ships. Functional requirements are typically ga

Question 6

How do you conduct effective stakeholder interviews to gather requirements for a new system or feature?

Accepted Answer

Stakeholder interviews are the primary method for understanding business needs, constraints, and priorities. Conducting them effectively requires preparation, active listening, and the ability to translate business language into technical understanding.

Before the interview, research the stakeholder's role and perspective. A CFO cares about cost and ROI, a product manager cares about features and timelines, a compliance officer cares about regulations and audit trails, and an operations manager cares about reliability and maintenance. Tailor your questions to their domain. Prepare a list of

Question 7

What is the difference between synchronous and asynchronous integration patterns, and when would you use each?

Accepted Answer

Synchronous and asynchronous integration patterns represent fundamentally different approaches to how systems communicate, and choosing correctly between them has a significant impact on system reliability, performance, and user experience.

In synchronous integration, the calling system sends a request and waits for a response before proceeding. This is the request-response pattern, most commonly implemented with REST or gRPC APIs. The caller is blocked until the response arrives or a timeout occurs. Synchronous integration is appropriate when the caller needs an immediate response to conti

Question 8

What is the API gateway pattern, and what problems does it solve in a distributed system?

Accepted Answer

An API gateway is a single entry point that sits between clients and a collection of backend services. It routes incoming requests to the appropriate service and handles cross-cutting concerns that would otherwise need to be duplicated across every service.

The API gateway pattern solves several problems in distributed systems. First, it simplifies the client experience. Without a gateway, a mobile application might need to call five different services to render a single screen, managing different URLs, authentication mechanisms, and response formats for each. The gateway provides a unified

Question 9

What are the main cloud pricing models such as on-demand, reserved, spot, and savings plans, and when is each most appropriate?

Accepted Answer

Cloud providers offer multiple pricing models that trade commitment flexibility for cost savings. Understanding these models is essential for building cost-effective architectures, and most production environments use a combination of several models.

On-demand pricing charges you by the hour or second with no commitment. You pay the full listed price but can start and stop resources at any time with no penalty. On-demand is appropriate for unpredictable workloads where you cannot forecast usage, short-term projects or experiments, initial development and testing before understanding resourc

Question 10

What is right-sizing in cloud computing, and how do you determine the appropriate instance types and sizes for a workload?

Accepted Answer

Right-sizing is the practice of matching cloud resource allocations to actual workload requirements so that you are not paying for unused capacity or suffering from insufficient resources. It is one of the most impactful cost optimization practices because over-provisioned resources are the single largest source of cloud waste in most organizations.

The process starts with understanding your workload's resource profile. CPU-bound workloads like computation, encryption, and data processing need compute-optimized instances. Memory-bound workloads like in-memory databases, caching, and large d

Solutions Architect

Topics

Cloud Fundamentals for Architects

System Design Basics

Requirements Gathering & Documentation

Integration Patterns

Cost Estimation & Sizing

Mock Interview

Quick Stats