The objective of this course is to prepare you for answering questions related to this domain. We’ll cover the need to know aspects of how to design Multi-Tier solutions using AWS services.

By the end of this course, you will be well prepared for answering questions related to Domain One in the Solution Architect Associate exam

Architecture basics 
You need to be familiar with a number of technology stacks that are common to multi-tier solution design for the Associate certification- LAMP, MEAN, Serverless and Microservices are relevant patterns to know for the exam. 

What is multi-tier?
A business application generally needs three things. It needs something to interact with users - often called the presentation layer -  it needs something to process those interactions - often called the logic or application layer - and it generally needs somewhere to store the data from that logic and interactions - commonly named as the data tier.

When should you consider multi-tier?
The key thing to remember is that the benefit of multi-tier architecture is that the tiers are decoupled which enables them to be scaled up or down to meet demand. This we generally call burst activity and is a major benefit of building applications in the cloud

When should we consider single-tier?
Single tier generally implies that all your application services are running on the one machine or instance. Single-Tier deployment is generally going to be a cost-effective and easy to manage architecture but speed and cost is about all there is for benefits. Single tier suits development or test environments where finite teams need to work and test quickly. Single tier can also suit very simple applications or small sites with low traffic demand which will benefit from the effective and economical resource utilization single tier allows

So Let’s move into design mode
First we review the design of a multi-tier architecture pattern using instances and load balances.  Then we’ll review how we could create a similar solution using serverless services or a full microservices design. Looking for the types of question material we might get in the exam/ 

AWS Services we use 
The Virtual Private Cloud
Subnets and Availability Zones 
Auto Scaling 
Elastic Load Balancers 
Security groups and NACLs
AWS CloudFront
AWS WAF and AWS Shield 

Serverless Design 
AWS Lambda 
Amazon API Gateway 

Microservices Design 
AWS Secrets Manager 
AWS KMS 

We then review sample questions to apply and solidify our knowledge 

Summary