Router

Firewall

Web server

Load balancer

The two different tiers are the application tier and the data tier.

A 2-tier architecture consists of a decentralized network of nodes that are both clients and servers.

The interface resides on client machines and makes requests to a server for data or services.

A 2-tier architecture consists of producers and consumers of events.

Microservices and event-driven

Peer-to-peer and two-tier

Peer-to-peer and event-driven

Three-tier and microservices

A unit of functionality that focuses on a solution to a business need, is deployed independently, and is reused by multiple systems.

A focus on the decomposition of a design into logical components.

It is a type of object.

A service defines, composes, and implements loosely coupled independent components so they work together to create an application.

They all use JavaScript.

They describe which parameters should be passed when instantiating an object.

They explain which methods should be included when coding an object.

They serve to bring new team members up to speed quickly.

UML diagrams

Software requirements specification (SRS)

Administrator user guide

Test cases

Designing a component so it operates in different environments.

A component’s design so it doesn’t have dependencies on other components.

A component should be easily replaced with another component.

Bundling data and methods to hide an internal state, so a component’s specific implementation is not exposed.

tightly cohesive

tightly coupled

loosely constrained

loosely cohesive

The choice of technology stack drives the software architecture.

It describes how the application should be coded.

It represents the earliest design decisions.

It captures implementation details.