Amazon Glacier vs AWS Storage Gateway: What are the differences?

Developers describe Amazon Glacier as "Low-cost storage service that provides secure and durable storage for data archiving and backup". In order to keep costs low, Amazon Glacier is optimized for data that is infrequently accessed and for which retrieval times of several hours are suitable. With Amazon Glacier, customers can reliably store large or small amounts of data for as little as $0.01 per gigabyte per month, a significant savings compared to on-premises solutions. On the other hand, AWS Storage Gateway is detailed as "Connect your on-premises IT environment with AWS’s storage infrastructure for data backup and disaster recovery". The AWS Storage Gateway is a service connecting an on-premises software appliance with cloud-based storage. Once the AWS Storage Gateway’s software appliance is installed on a local host, you can mount Storage Gateway volumes to your on-premises application servers as iSCSI devices, enabling a wide variety of systems and applications to make use of them. Data written to these volumes is maintained on your on-premises storage hardware while being asynchronously backed up to AWS, where it is stored in Amazon Glacier or in Amazon S3 in the form of Amazon EBS snapshots. Snapshots are encrypted to make sure that customers do not have to worry about encrypting sensitive data themselves. When customers need to retrieve data, they can restore snapshots locally, or create Amazon EBS volumes from snapshots for use with applications running in Amazon EC2. It provides low-latency performance by maintaining frequently accessed data on-premises while securely storing all of your data encrypted.

Amazon Glacier and AWS Storage Gateway can be primarily classified as "Data Backup" tools.

Some of the features offered by Amazon Glacier are:

• Low cost – Amazon Glacier is an extremely low-cost, pay-as-you-go storage service that can cost as little as $0.01 per gigabyte per month.
• You store data in Amazon Glacier as archives. An archive can represent a single file or you may choose to combine several files to be uploaded as a single archive. Retrieving archives from Amazon Glacier requires the initiation of a job. Jobs typically complete in 3 to 5 hours. You organize your archives in vaults.
• Secure – Amazon Glacier supports secure transfer of your data over Secure Sockets Layer (SSL) and automatically stores data encrypted at rest using Advanced Encryption Standard (AES) 256, a secure symmetric-key encryption standard using 256-bit encryption keys.

On the other hand, AWS Storage Gateway provides the following key features:

• Gateway-Cached Volumes – Gateway-Cached volumes allow you to utilize Amazon S3 for your primary data, while retaining some portion of it locally in a cache for frequently accessed data.
• Gateway-Stored Volumes – Gateway-Stored volumes store your primary data locally, while asynchronously backing up that data to AWS.
• Data Snapshots – Gateway-Cached volumes and Gateway-Stored volumes provide the ability to create and store point-in-time snapshots of your storage volumes in Amazon S3.