If you think of the blockchain as a chain and the tangle as a knotted net, the hashgraph is a tree. Just like the tangle, Hashgraph wants to solve the problem of scalability. In contrast to IOTA, however, Hashgraph has “only” to do with a data structure without an associated crypto currency. Hashgraph is currently only a technical framework and designed to create infrastructures for companies and the like.
Gossip over Gossip
In the Gossip-over-Gossip method, the individual nodes communicate what the other nodes have “said”. If you like, each gossip node spreads the information to other gossip nodes. All participants regularly synchronize their information with randomly selected other participants to ensure that it is up to date.
In order to validate information, Hashgraph works with polls. The gossip principle ensures that the validated information is passed on to all nodes and thus remains up-to-date at all times. The nodes coordinate with each other and thus validate the information. Thus it is a chain of points that links the individual nodes – the information about who has communicated with whom is stored in the hash – all hashs together form the hash graph. Hashgraph is, figuratively speaking, a constantly growing tree whose fruits spread gossip among themselves.
From a technical point of view, this has the advantage that only a minimum of bandwidth is needed to spread the gossip further. Each time the gossip is spread, the participants only add a minimum amount of information without distorting it.
Both IOTA’s Tangle and Hashgraph promise high scalability and thus fast, secure and energy-efficient transactions. In contrast to the Bitcoin blockchain, however, there are no miners, transactions are validated at Tangle with new transactions that are (currently) ordered by a coordinator. Hashgraph, on the other hand, uses the Gossip-over-Gossip method, in which they pass on information about hashs and validate it in the voting process.
The network now offers a distributed consensus system (Distributed Consensus Algorithm). As with the Tangle, this allows several parallel computing processes, Hashgraph promises above all to be more efficient and faster.
As consensus procedure Hashgraph uses the Gossip-over-Gossip principle (gossip about gossip). In this way, the developers hope to circumvent the problem of the so-called Byzantine error. In short, the aim is to prevent the (exponential) spread of misinformation in a decentralized system.
Of course, there are other approaches in distributed ledger technology and new ones are constantly being added. In the case of crypto currencies, our New Coins on the Block series therefore repeatedly presents new, distributed data structures.