Book Image

AWS Certified Developer - Associate Guide

By : Vipul Tankariya, Bhavin Parmar
Book Image

AWS Certified Developer - Associate Guide

By: Vipul Tankariya, Bhavin Parmar

Overview of this book

AWS Certified Developer - Associate Guide starts with a quick introduction to AWS and the prerequisites to get you started. Then, this book gives you a fair understanding of core AWS services and basic architecture. Next, this book will describe about getting familiar with Identity and Access Management (IAM) along with Virtual private cloud (VPC). Moving ahead you will learn about Elastic Compute cloud (EC2) and handling application traffic with Elastic Load Balancing (ELB). Going ahead you we will talk about Monitoring with CloudWatch, Simple storage service (S3) and Glacier and CloudFront along with other AWS storage options. Next we will take you through AWS DynamoDB – A NoSQL Database Service, Amazon Simple Queue Service (SQS) and CloudFormation Overview. Finally, this book covers understanding Elastic Beanstalk and overview of AWS lambda. At the end of this book, we will cover enough topics, tips and tricks along with mock tests for you to be able to pass the AWS Certified Developer - Associate exam and develop as well as manage your applications on the AWS platform.
Table of Contents (29 chapters)
Title Page
Credits
About the Author
Acknowledgments
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface
Index

Subnets


Subnet is short for subnetwork. As we saw at the beginning of this chapter, a network is subdivided into multiple logical parts for controlling access to individual logical subparts of the network. When we create a subnet, we need to specify a unique CIDR block for the subnet. This CIDR block has to be a subset of the VPC CIDR block. Each subnet must reside entirely within a single AZ as a subnet cannot span multiple AZs.

Subnets are categorized as public and private subnets based on their security profile, or in other words, based on their route table. We will now discuss different types of subnets.

Private subnets

A private subnet is a subset of a network wherein resources within a subnet are isolated and restricted for access from within the VPC. Any incoming traffic from the internet cannot directly access the resources within a private subnet. Similarly, outgoing traffic from a private subnet cannot directly access the internet. Outgoing traffic to the internet is either restricted...