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Table of contents
What is Amazon S3
How Amazon S3 works
Amazon S3 Data Consistency Model
Concurrent Applications
Accessing Amazon S3
AWS Management Console
AWS Command Line Interface
Amazon S3 REST API
Services related to Amazon S3
PCI DSS Compliance
Advantages of Amazon S3 
Frequently Asked Questions
What are some features of Amazon S3?                                   
What is the maximum size for an Amazon S3 bucket?
How can we list objects on a bucket in Amazon S3?
Last Updated: Mar 27, 2024

Amazon S3

Author Vidhi Singh
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Amazon provides a number of Storage and Content Delivery Services. Amazon S3 is one such service. In this article, we will discover Amazon s3 in depth.

What is Amazon S3

S3 is short for Simple Storage Service. Amazon Simple Storage Service(S3)is a web-based cloud storage service that is highly efficient and scalable as well. It offers high performance, data availability, and secure service in many leading industries. This service is designed for the archiving and online backup of data on AWS.

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How Amazon S3 works

As discussed earlier, that amazon s3 is an Object Cloud Storage service that stores data within the buckets. It is different from other cloud storage services like block and file storage services.

Components used in the working of amazon s3 are:

  • Buckets: A bucket in amazon s3 is a container used for storing objects. We can store any number of things in our bucket.
  • Objects: Objects consists of the file and its metadata. The metadata is a set of name-value that describes the object.
  • Keys: A key name for an object is its unique identifier within a bucket. Within a bucket, each object has its unique key.
  • S3 versioning: It is used to preserve, restore and retrieve multiple types of objects in a single bucket. 
  • Version ID: When s3 versioning is enabled, amazon s3 creates a version ID for an object we add to the bucket. The objects already in a bucket before enabling s3 versioning have a null version ID.
  • Bucket policy: A bucket policy in amazon s3 is a resource-based AWS and IAM policy used to grant permissions to the bucket and its objects. Only the owner of the bucket can associate his bucket with the policy.
  • S3 access point: s3 access point is named the endpoint's network with access policies used to describe how data can be accessed using endpoints. It simplifies managing data access for datasets in amazon s3.
  • Access control list (ACL): ACLs are used to grant users permission to read and write for individual buckets and objects.
  • Regions: We can choose the AWS region where amazon s3 stores our bucket to optimize latency, address regulatory requirements and minimize cost. 

We first create a bucket and specify its name and region to store data. Then we upload our data as objects in the bucket. Each object has its unique identifier and is stored as a file that stores the metadata. Objects also have an ID number used by applications to access these objects. Amazon s3 allows customers to store, upload and download any file.

Amazon S3 Data Consistency Model

  • Amazon s3 has high availability as it replicated data across multiple servers within AWS data centers. It provides strong read-after-write consistency for delete and put requests. It is applied to both when we write a new object and when we put a request to overwrite existing objects.
  • If a put request is successful, our data is stored safely. Any other request initiated after the put request will return data written by the put request. For example :
  • A process replaces an existing object and instantly makes efforts to read it, then amazon s3 will return new data.

Concurrent Applications

This section is used with examples of behavior expected from amazon s3 when many clients write to the same items. For example:

Both W1and W2 finish before R1 and R2 are started. Since S3 is strongly consistent, R1 and R2 return color-ruby.

Let's see another example: 

W2 begins before W1. Therefore, these writes across multiple servers are considered concurrent. Amazon S3 internally uses last-writer-wins semantics to determine which write takes precedence. 

Bucket configurations have an eventual Consistency Model. By Consistency Model, it implies the following:

  • If a bucket is deleted and immediately all buckets all listed, the deleted bucket might still appear in the list.
  • If versioning on a bucket is enabled for the first time, it might take a short amount of time for the change to be fully propagated. It is recommended to wait for at least 15 minutes after enabling versioning before issuing write operations (PUT or DELETE requests) on objects in the bucket.

Accessing Amazon S3

There are mainly four(4) ways through which Amazon s3 can be accessed. Let us look into these ways in detail:

AWS Management Console

This console is a web-based interface used for managing amazon s3 resources. You can access the amazon s3 console by simply signing into the AWS management console.

AWS Command Line Interface

AWS command-line interface tools can be used to issue commands or build scripts on users' system command line to perform tasks. It provides command lines for various AWS services.


AWS software development kit consists of a library and samples for various programming languages code. It provides a convenient way to create programmatic access to amazon s3 and AWS.

Amazon S3 REST API

Amazon s3 rest API can be used to access amazon s3 and AWS programs. An HTTP interface is used to create, fetch, and delete objects and buckets.

Services related to Amazon S3

After adding data in amazon s3, we can also use it with other AWS services.

  • Amazon elastic compute cloud(Amazon EC2): This provides scalable and secure capacity for computing in AWS. We can use Amazon EC2 to launch a few virtual servers as required and manage storage.
  • Amazon EMR(Amazon Elastic MapReduce): It uses the Hadoop framework for running on the web-scale infrastructure of amazon s2 and s3 and helps in easy and cost-effective data processing for businesses.
  • AWS Transfer Family: It supports file transfers into and out of Amazon EFS. It uses a secure shell file transfer protocol, file transfer protocol, and file transfer protocol over SSL.

PCI DSS Compliance

PCI DSS stands for Payment Card Industry Data Security Standard. It is an information security standard. The PCI Security Standards Council administers it. Amazon S3 supports the storage, processing, and transmission of data from credit cards by a service provider or merchant and has been validated as being compliant with Payment Card Industry (PCI) Data Security Standard (DSS). 

Advantages of Amazon S3 

A few of the benefits of Amazon s3 include:

  • Low cost: S3 lets users store data in a range of “storage classes.” These classes are based on the required immediacy and frequency for accessing the file.
  • Scalability: S3 charges users only for what resources they actually use, and there are no hidden fees or overage charges. Storage resources can be scaled easily to meet organization’s ever-changing demands.
  • Availability: S3 offers 99.99 percent object availability.
  • Security: S3 provides encryption features that provide top-notch security and an impressive range of access management tools.
  • Flexibility: S3 is considered ideal for a wide range of uses such as data backup,data storage, software delivery, disaster recovery, data archiving, website hosting, mobile applications, IoT devices, and much more.
  • Simple data transfer: Users don’t have to be an IT genius to execute data transfers on S3. The service revolves around ease of use and simplicity.

Frequently Asked Questions

What are some features of Amazon S3?                                   

It helps in managing access to objects and buckets. It is also used to store data and cheaper price.

What is the maximum size for an Amazon S3 bucket?

A bucket in amazon s3 can store an unlimited amount of objects.

How can we list objects on a bucket in Amazon S3?

We use the ‘ aws s3 ls --recursive ‘ command to list all objects to files in the bucket.


This article extensively discusses Amazon s3, its working, related services and accessing. 
Read more articles on AWS to enrich your knowledge on the topic.

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