Hedera Hashgraph is a third-generation Distributed Ledger Technology (DLT) that aims to address the shortcomings of first and second-generation DLTs, namely Bitcoin and Etherium. Hedera Hashgraph uses a fundamentally different algorithm than those used by these earlier technologies, called Gossip about Gossip or simply “G2.”
The Hashgraph algorithm is a patented algorithm that offers many of the blockchain benefits (decentralization, distribution, and security) but not the drawback of slow transaction times. It was developed by Leemon Baird and is the intellectual property of the Swirlds Corporation, which Baird founded.
Hedera Hashgraph is a new blockchain-like protocol that can support thousands of transactions per second. This is possible because the network uses a gossip protocol instead of the traditional blockchain protocol. While the blockchain protocol is great for security, it’s inefficient because all transactions have to be processed by every node on the network. Moreover, the blockchain is designed to be immutable, so any change requires a majority of the nodes to agree on the change. The Hedera Hashgraph is a distributed public ledger that uses a gossip protocol. A gossip protocol is a way to exchange messages in a peer-to-peer network where the messages are copied to everyone in the network.
The Hashgraph algorithm operates through two techniques. The first technique is known as Gossip about Gossip and is used for sharing information.
Let’s suppose we have five Humans: H1, H2, H3, H4, and H5. Each Human starts with a transaction, which results in an ‘event.’ Each Human then calls another randomly selected Human and shares their transaction history with the other. H4 calls H2 and tells him about his transaction history. This kind of calls keeps happening, with each member randomly calling another member and sharing their transaction history. H2 now randomly selects another Human (let’s say H3) and shares its transaction history, including H4‘s as well. In parallel, H5 may have called H1, and so on. Each call results in an event, which contains the hashes of all previous blocks in the chain.
Virtual voting is a new consensus algorithm developed by Swirlds. It is known by the community as the “world’s first fair byzantine fault tolerant consensus algorithm“. Virtual voting is capable of reaching consensus among an uneven number of nodes. To compensate for the uneven number of nodes, virtual voting utilizes a combination of round-robin and random selection. This allows the system to reach consensus and secure information in a fair manner. One of the most important features of virtual voting is the ability to maintain consensus even under the threat of Byzantine faults. Byzantine fault tolerance is achieved by requiring two-thirds of the nodes to agree on a transaction. When a node doesn’t agree with the transaction,it simply won’t propagate the transaction to other nodes. The remaining two-thirds of the nodes will continue to push the transaction until it becomes agreed upon by all participating nodes.