You're reading from System Design Guide for Software Professionals Build scalable solutions – from fundamental concepts to cracking top tech company interviews

Product type Paperback

Published in Aug 2024

Publisher Packt

ISBN-13 9781805124993

Length 384 pages

Edition 1st Edition

Concepts

Application Development

Authors (2):

Dhirendra Sinha

Tejas Chopra

View More author details

Table of Contents (21) Chapters

Preface

1. Part 1: Foundations of System Design

2. Chapter 1: Basics of System Design FREE CHAPTER

3. Chapter 2: Distributed System Attributes

4. Chapter 3: Distributed Systems Theorems and Data Structures

5. Part 2: Core Components of Distributed Systems

6. Chapter 4: Distributed Systems Building Blocks: DNS, Load Balancers, and Application Gateways

7. Chapter 5: Design and Implementation of System Components –Databases and Storage

8. Chapter 6: Distributed Cache

9. Chapter 7: Pub/Sub and Distributed Queues

10. Part 3: System Design in Practice

11. Chapter 8: Design and Implementation of System Components: API, Security, and Metrics

12. Chapter 9: System Design – URL Shortener

13. Chapter 10: System Design – Proximity Service

14. Chapter 11: Designing a Service Like Twitter

15. Chapter 12: Designing a Service Like Instagram

16. Chapter 13: Designing a Service Like Google Docs

17. Chapter 14: Designing a Service Like Netflix

18. Chapter 15: Tips for Interviewees

19. Chapter 16: System Design Cheat Sheet

20. Index

Scalability, reliability, and consistency in DNS

When we talk about any large-scale system, especially something as vast as DNS, there are three buzzwords that often come up: scalability, reliability, and consistency. These are like the three pillars that hold up any robust system. Let’s dive into how DNS checks off these crucial boxes.

Scalability

The DNS achieves high scalability through its hierarchical design with root, top-level domain, and authoritative name servers distributed worldwide. Roughly 1,000 replicated instances of 13 root-level servers handle the initial user queries. They point to TLD servers, which, in turn, point to authoritative servers managed by individual organizations. This hierarchical structure divides the load between different levels, allowing DNS to scale to serve billions of daily queries for the entire internet.

The distributed nature of DNS also contributes to its scalability. Redundant replicated DNS servers are located strategically...