Hashgraph, what's it and how does it work?

Question

Does anyone know what's a hashgraph and the difference from blockchain? If you could explain it to me how it works, I would be pleased! Thank you in advance!

Answer 1

Hedera does not use blockchain. It uses DAG, "Directed Acyclic Graph. it keeps the records of communication of all the nodes in Dag and time stamps all these messages. Sending messages between nodes is called gossiping`. Its source code is not open source.

How does the gossip protocol work

In hashgraph, when sending information between nodes, "Alice" will choose another member at random, such as "Bob". Then Alice will tell Bob all of the information she knows so far. Alice then repeats this information with a different random member. Bob repeatedly does the same, and all other members do the same. In this way, if a single member becomes aware of new information, it will spread exponentially fast through the community, until every member is aware of it.

The synchronization of information between two members through the gossip protocol is called a gossip sync. Upon completion of a gossip sync, each participating member commemorates the gossip sync with an event. An event is stored in memory as a data structure composed of a timestamp, an array of zero or more transactions, two parent hashes, and a cryptographic signature. The two parent hashes are the hash of the last event created by the self-parent prior to the gossip sync and the hash of the last event created by the other-parent prior to the gossip sync.

Gossiping is the basis of the hashgrap consensus algorithm which uses asynchronous byzantine fault tolerant (abft) . this indicates that there is no specific time when all the nodes reach consensus. In other words abft consensus mechanism has no block time. (there is no blockchain here. neither a block reward)

Since gossiping the fastest way of sperading information, it takes 3-5 seconds for the entire network to reach a consensus.

Hedera claims that the network achieves 10,000 HBAR cryptocurrency transactions per second. (i personally do not believe those claims)

You can also write smart contracts on Hedera. But you cannot execute 10000 smart contract operations per second because Hedera uses EVM and EVM is very slow.

Hedera has no slashing. If validators misbehave, they will not lose any of their crypto holdings. because they claim that hedera hashgraph gives validators less opportunity to misbehave. validators receive the 90% of the network fees.

Answer 2

Hedera Hashgraph is very much different from a regular Blockchain (which is a chain of blocks as its name suggests), it is a DAG (Directed Acyclic Graph).

You can read more about what a DAG is in the link provided but apart from that how Hedera is different is that it is solving the below problems that any DLT should overcome to become Scalable, Secure and Fast without losing Trust:

(1) Performance, (2) Security, (3) Governance, (4) Stability, (5) Regulatory Compliance.

How is it solving all this simultaneously without losing Trust is something that you can read more in their whitepaper which explains beautifully or refer this article from Rejolut.

One primary problem with any Public Blockchain is the TPS or Transaction per second it can handle and Hedera Hashgraph is miles ahead of the others with being able to clock 100,000 TPS which makes it valuable and preferred option as it offers services like Crypto Service, File Service, Smart Contract Service and Consensus Service.

You can have a look at some of the explorers like Kabuto and Dragonglass to get an idea of the transaction speed and other details.

If you want to play around with Hedera Hashgraph, their docs are very well written or you can use console playground to work on Smart contract and Consensus services directly and maybe use fairorder to do the account management for you to begin with.