Beginner’s Guide to HashGraph – The Competitor to Blockchain
Blockchain – The Solution to Centralization
The advent of a decentralized, distributed, and self-fulfilling platform, i.e., Blockchain, has revolutionized the way we exchange value and information with each other for good. In many ways, blockchain will help us move away from the world with central regulatory bodies, needed for brokering trust, and towards a decentralized trust-less ecosystem. A world where technology shoulders the responsibility of federating the trust.
Belief is that Satoshi Nakamoto, the anonymous inventor(s) of Bitcoin and Blockchain technology, wouldn’t have imagined that their novel invention would go on to break traditions and institutions in the way it has done today. Blockchain technology came to a renewed interest in the idea of a utopian decentralized world where everyone works for everyone and no single authority is given a chance to take advantage.
With Pros Come Cons
But then, as we always say, not everything is perfect. Sure, blockchain might end up changing the way we transact value and information for good. But with the innovation in decentralized technologies came problems that were unique to it and it alone. A blockchain is a disruptive technology, but it has its fair share of issues. The proof-of-work algorithms needed to validate transactions are slow and resource-intensive. A few transactions per second is snail-paced compared to the millions of transactions we do over the internet.
Since 2010, innovators have been trying to build upon the Bitcoin blockchain by identifying its flaws and trying to solve them by building clever and innovative infrastructures. But what is to be noted is that no matter how much one tries to improve on a blockchain project by bringing in another blockchain project, problems that are inherent to blockchain technology cannot be changed. Many realized that there was going to be an imminent update to blockchain technology that would borrow its basic principles and try to innovate in its way.
Introducing Hedera HashGraph – The Blockchain 2.0
As per Wikipedia, “HashGraph is a distributed ledger technology developed by Leemon Baird, the co-founder and CTO of Swirlds, in 2016. It is an asynchronous Byzantine Fault Tolerance (aBFT) consensus algorithm that they consider capable of securing the platform against attacks. It does not use miners to validate transactions and uses directed acyclic graphs for time-sequencing transactions without bundling them into blocks.”
HashGraph is a DLT platform, which employs Gossip protocol for consensus building. It was made to provide a fast, fair, and secure infrastructure to initially run Decentralized applications (dApps) but can increase its scope in the future.
HashGraph works on a gossip-based protocol which is fundamentally not a new idea. In a gossip-based system, nodes communicate with each other and tell each other information that they know. For instance, communicating the current state of the network, communicating nodes trusted by a node, and so on. Upon receiving this gossip, these nodes will then gossip this information out to other nodes, forming a network where every node eventually knows about every other node.
The innovative idea that distinguishes HashGraph from traditional gossip systems, is that rather than just gossiping arbitrary data, nodes gossip about gossip, i.e. the data structure in the image on the left is stored in memory and sent to others. Intuitively, if you imagine each node in the diagram to represent a new transaction being added to the graph, then rather than just sending that node, when a host gossips, they will send a whole tree of nodes starting from the new one.
Delving Deeper into the Properties of HashGraph
To achieve consensus, HashGraph uses two techniques – Gossip about gossip and Virtual voting.
Gossip about gossip means sharing information about the information being spread. This is achieved by adding a tiny amount of additional information, a couple of hashes about the people spreading the gossip (the parent nodes). This helps in creating a historical graph of information being disseminated.
The information that is transmitted from a node is disseminated as gossip, which is through a random selection of peers to share what you know. The idea is to share the information with as many participants as possible, if not all. Interestingly, epidemics spread in the same way (boy oh boy!). It has been mathematically proven that gossiping is the fastest way of spreading news, and HashGraph builds on it.
Virtual Voting is used to build a consensus on the ordering and timestamp of the gossips (the transactions). In simple words, the participants take turns in voting on what they know and when they came to know about it. It’s virtual, as each participant simulates the voting, using an algorithm, to arrive at a consensus on ordering and timestamps. Actual voting is not necessary, as all participants already have a copy of the same data-set and are supposed to arrive at the same voting results, which is also mathematically proven. This increases the speed with which a consensus is arrived at.
Blockchain vs. Hashgraph
By many standards, HashGraph looks like the perfect replacement for the Blockchain. HashGraph improves upon many of the flaws of the blockchain infrastructure, by solving them from the ground up. This allows applications that are built on HashGraph to be wary of the fundamental flaws of the blockchain system, thereby being more efficient and optimized.
- Fast – more than 250,000 transactions per second and very low latency (in seconds)
- Fair – it ensures fairness in consensus on ordering and timestamps, and also fairness in access, which is key to any distributed ledger system
- Secure – it is tolerant against behaviors like lying, collusion, and selective non-participation, which is quite essential for distributed ledgers. In technical works, it is Asynchronous Byzantine Fault Tolerant, which is the gold standard for security in distributed systems.
HashGraph is an innovative update to a blockchain. It uses a traditional piece of technology called the Gossip Network to improve the fundamental flaws of the blockchain. In many ways, HashGraph sure does look like it should have replaced Blockchain already.
But then, just like Blockchain, HashGraph too has its fair share of trade-offs. What it gains in efficiency and optimization, HashGraph loses in decentralization and openness. To work at full capacity, HashGraph has to work in a relatively closed environment when compared to a blockchain. Blockchain thrives in distribuends, meaning that the greater the number of participants, the more its strength. Whereas, HashGraph can function in a distributed environment, but the efficiency of the network declines with an increase in the number of participants.
And so, HashGraph should not be viewed as a replacement for blockchain, as many “market experts” have confidently claimed. HashGraph and Blockchain are like Pepsi and Coca-Cola of the technology world. Each side has its advantages and trade-offs, which gives prospective users the ability to weigh their options and choose the best infrastructure that suits their needs.