What is ADD?

ADD (Architecture Design Document) is a document that describes the overall system architecture and technical design of a software application.

 It explains how the system is structured, how components interact, and what technologies are used.

This document helps developers, architects, and testers understand the system design.

History of ADD

The concept of documenting system architecture became important in the 1990s when software systems became large and complex.

Software architects started creating Architecture Design Documents to clearly describe:

• System structure

• Components

• Technology stack

• Communication between modules

Organizations like IEEE and frameworks such as The Open Group encouraged structured architecture documentation.

Today, ADD is a standard practice in software engineering and enterprise system design.

How ADD Document is Created

The Software Architect or Technical Architect usually prepares the ADD.

Steps to Create ADD

1️⃣ Understand Business Requirements
Requirements are first collected from the BRD (Business Requirement Document).

2️⃣ Analyze Functional Requirements
Detailed system functionality is studied from the FRD (Functional Requirement Document).

3️⃣ Design System Architecture
The architect decides:

• Application layers

• Components

• Communication flow

How ADD Document is Created

4️⃣ Select Technology Stack

Example:

• Programming language

• Database

• Framework

• Cloud platform

5️⃣ Create Architecture Diagrams

Examples include:

• System architecture diagram

• Component diagram

• Data flow diagram

6️⃣ Document Security and Performance Design

Includes:

• Authentication methods

• Data encryption

• Scalability planning

 Key Contents of ADD

Typical sections in an ADD include:

• System architecture overview

• Technology stack

• Component design

• Database design

• Integration details

• Security architecture

• Deployment architecture

Real-World Example

For an online banking system, the ADD may define:

Frontend: Web application
 

Backend: Application server
 

Database: Customer and transaction data
 

Cloud: Amazon Web Services

Architecture Flow:

User → Web Application → Application Server → Database

 Purpose of ADD

1️⃣ Define system architecture clearly

2️⃣ Help developers understand technical design

3️⃣ Improve system scalability and maintainability

4️⃣ Provide a reference for development and testing

 Who Creates ADD, BRD, and FRD?

BRD (Business Requirement Document)

FRD (Functional Requirement Document)

ADD (Architecture Design Document)

 Simple Project Flow

BRD Example (Business Requirement)

The bank wants a mobile banking application where customers can:

• Check account balance

• Transfer money

• View transaction history

 This is written in the BRD.

Focus:
Business goals and user needs.

 FRD Example (Functional Requirement)

The system must provide the following features:

• User login with username and password

• Balance check option

• Fund transfer functionality

• Transaction confirmation message

 These detailed features are written in the FRD.

Focus:
System functionality.

SRS Example (Software Requirement Specification)

The SRS document contains both:

Functional Requirements

• Login system

• Fund transfer

• Balance check

Non-Functional Requirements

• System response time < 3 seconds

• Secure authentication

• 99.9% system availability

 SRS gives complete software requirements

ADD Example (Architecture Design)

The system architecture is defined in the ADD.

Example architecture:

User Mobile App
⬇
Application Server
⬇
Database Server

Technologies used:

• Frontend → Mobile App

• Backend → Application Server

• Database → MySQL

These technical design details are written in ADD

Simple Flow of Documents in a Project

Easy Way to Remember

One-Line ANSWER