AWS QLDB : Theory

Amazon QLDB :

Amazon QLDB offers a fully managed ledger database. It offers all the key features of a blockchain ledger database including immutability, transparency and cryptographically verifiable transaction log. However, QLDB cis owned by a central trusted authority. So, in a sense, it has almost all the features of a distributed ledger technology with a centralized approach.

Also, you can’t compare Amazon QLDB vs blockchain as the two have some fundamental differences. QLDB is launched along with Amazon Managed Blockchain.

Amazon QLDB Use-Cases :

In this section, we will take a look at the Amazon QLDB use-cases. The Amazon QLDB use-cases are important to get a complete glimpse of what QLDB has to offer.

Manufacturing :

The manufacturing companies can take full advantage of what QLDB Amazon has to offer. In manufacturing, it is important for companies to make sure that their supply chain data matches that of the supply chain. With QLDB, they can record every transaction and its history. As we’re already seeing blockchain in manufacturing, QLDB will only make things more efficient.

This means that each of their individual batches will be properly documented. In the end, they will be equipped with the knowledge of tracing the parts if something goes wrong during the distribution life cycle of a product.

QLDB Customers and Partners :

At the time of writing, QLDB has made strong partners and has also acquired customers. Some of them include the following.

• Digital Asset
• Accenture
• Asano
• Realm
• Wipro
• Zillant
• Splunk
• Klarna.

How it Works :

Common Use Cases

• Finance
  • Banks can use Amazon QLDB to easily store an accurate and complete record of all financial transactions, instead of building a custom ledger with complex auditing functionality.
• Insurance
  • Insurance companies can use Amazon QLDB to track the entire history of claim transactions. Whenever a conflict arises, Amazon QLDB can cryptographically verify the integrity of the claims data.

Components Of QLDB :

• Ledger :
  • Consists of tables and journals that keep all of the immutable histories of changes in the table.
• Tables :
  • Contains a collection of document revisions.
• Journal :
  • An immutable transactions log where transactions are appended as a sequence of blocks that are cryptographically chained together to provide a secure verification and immutability of the history of changes to your ledger data.
  • Only the data’s history of change cannot be altered and not the data itself.
• Current State
  • The current state is similar to a traditional database where you can view and query the latest data.
• History :
  • The history is a table where you can view and query the history of all the data and every change ever made to the data.

Performance :

• Amazon QLDB can execute 2 – 3X as many transactions than ledgers in common blockchain frameworks.

Scalability :

• Amazon QLDB automatically scales based on the workloads of your application.

Reliability :

• Multiple copies of QLDB ledger are replicated across availability zones in a region. You can still continue to operate QLDB even in the case of zone failure.
• Ensures redundancy within a region.
• Also ensures full recovery when an availability zone goes down.

Backup and Restore :

• You can export the contents of your QLDB journals to S3 as a backup plan.

Security :

• Amazon QLDB uses SHA-256 hash function to make a secure file representation of your data’s change history called digest. The digest serves as a proof of your data’s change history, enabling you to go back at a point in time to verify the validity and integrity of your data changes.
• All data in transit and at rest are encrypted by default.
• Uses AWS-owned keys for encryption of data.
• The authentication is done by attaching a signature to the HTTP requests. The signature is then verified using the AWS credentials.
• Integrated with AWS Private Link.

Pricing :

• You are billed based on five categories
  • Write I/Os
    • Pricing per 1 million requests
  • Read I/Os
    • Pricing per 1 million requests
  • Journal Storage Rate
    • Pricing per GB-month
  • Indexed Storage Rate
    • Pricing per GB-month
  • Data Transfer OUT From Amazon QLDB To Internet
    • You are charged based on the amount of data transferred per month. The rate varies for different regions.

Limitations :

• Amazon QLDB does not support Backup and Restore. But you can export your data from QLDB to S3.
• Does not support Point-in-time restore feature.
• Does  not support cross-region replication.
• Does not support the use of customer managed CMKs (Customer Managed Keys).