Cryptocurrencies and blockchain technology, once mere buzzwords, have now become central topics of financial and technological discussions. While many have heard about “blockchain” or “Bitcoin,” the underlying technologies that power these innovations remain mysterious to most.

One critical mechanism is aBFT, or Asynchronous Byzantine Fault Tolerance. It plays a silent but crucial role, ensuring that transactions and data on blockchains are both secure and efficient.

In this article, you will find what you need to know about aBFT – what it is and which crypto projects using it.

Byzantine General Problem in aBFT (Asynchronous Byzantine Fault Tolerance)

What is aBFT?

aBFT can be best understood by breaking down its name:


In the digital world, many processes run concurrently. An asynchronous system doesn’t wait for one task to finish before starting another, leading to faster operations. Imagine being in a busy office where everyone can complete tasks independently without waiting for their colleagues.

Byzantine Fault Tolerance (BFT)

This concept originates from a theoretical problem called the Byzantine Generals’ Problem. In this scenario, multiple generals need to coordinate an attack, but some might be traitors sending deceptive messages. BFT is a solution ensuring that a majority decision can be made even with the presence of such deceptive elements. In the world of blockchain, this ensures the network continues to function even if some participants (nodes) are malicious or faulty.

When combined, aBFT ensures a system that can effectively handle malicious attempts and still reach a consensus, and it does this without waiting for every participant to respond, making the entire process efficient.

How aBFT Works

Understanding aBFT at a high level requires delving into how consensus mechanisms function in decentralized systems. In simple terms, a consensus mechanism ensures that every participant in a network agrees on the state or value of data. For blockchains and similar technologies, it means every participant agrees on the validity of transactions.

1. Participant Communication

In an aBFT system, participants, often referred to as “nodes,” communicate with each other to share transaction data. These nodes can be anywhere in the world, and they don’t rely on synchronized clocks.

2. Voting and Validation

Nodes in the system vote on the authenticity of a transaction. Here’s where the Byzantine Generals’ Problem analogy applies: even if some nodes are malicious or faulty and vote falsely, the system can still reach a majority agreement based on the honest votes.

3. Threshold of Agreement

Not every single node must validate a transaction. Instead, there’s a threshold, typically more than two-thirds of the nodes, that must come to an agreement for a transaction to be validated. This setup ensures swift processing, as the system doesn’t have to wait for 100% participation.

4. Consensus and Confirmation

Once the required threshold of nodes agrees on the validity of a transaction, consensus is reached, and the transaction is confirmed. The beauty of aBFT is that once consensus is achieved, it’s irreversible and final, meaning there’s no need for multiple confirmations, as seen in some other blockchain systems.

5. Handling Malicious Nodes

One of the standout features of aBFT is its robustness against malicious attacks. Due to the threshold-based agreement, even if malicious nodes try to disrupt the system or feed false information, as long as they don’t form a majority (which is typically hard to achieve), the system remains unaffected and continues to function correctly.

In essence, aBFT offers a balanced approach: it ensures that transactions are both secure (safe from malicious intentions) and efficient (quick confirmations without the need for every node’s input).

Crypto Projects Using aBFT

The efficiency and security promises of aBFT have made it popular among many crypto projects:

1. Hedera Hashgraph

Unlike the linear progression of traditional blockchains, Hedera Hashgraph brings a unique approach. By leveraging aBFT, it offers transaction speeds unseen in many other blockchain architectures, ensuring both fairness and speed.

Learn more: Hedera Whitepaper

2. Algorand

A public blockchain aiming for decentralization without compromising speed. Algorand’s consensus mechanism, inspired by aBFT, ensures that all users can participate, be protected, and experience quick transaction times.

Learn more: Algorand’s Byzantine Agreement

3. Zilliqa

Zilliqa introduces sharding, a method to handle many transactions simultaneously. Its consensus mechanism, while based on sharding, draws inspiration from practical Byzantine Fault Tolerance, a variant of aBFT.

Learn more: Zilliqa Technical Whitepaper


aBFT, though a complex term, represents the future of secure and rapid decentralized systems. Its importance is not limited to just tech enthusiasts or crypto traders. As the world moves increasingly towards decentralized digital solutions, understanding the pivotal role of technologies like aBFT becomes essential for everyone.

Whether you’re investing, building, or just curious, aBFT is a testament to how innovation ensures trust in the digital age.

About The Author


Owner of Since 2013, he's been immersed in the world of cryptocurrencies and has become an avid NFT collector since 2019. Also an NFT artist, he is a lifelong learner of mixed-media artwork creation.