Monash Uni claims reputation-based blockchain capable of defending itself

The miner has their 'reputation' lowered to prevent malicious activity, the university says.
Written by Asha Barbaschow, Contributor

Researchers at Monash University have claimed the development of a blockchain system that is capable of defending against malicious activity, or at least making it very expensive for the attacker to do so.

According to Monash, its RepuCoin system introduces the concept of "reputation" to blockchain. The university believes that its system makes recoding blockchain information very hard.

"When RepuCoin has operated for a year, attacking the system with 68 percent of its total mining power would take at least six months and would be at least 5,760 times as expensive as conducting the same attack on bitcoin," Dr Jiangshan Yu from Monash said.

The university believes its RepuCoin would make recoding the blockchain's data and using it for malicious purposes, such as reversing government decisions, "thousands of times more expensive to attack than bitcoin".

RepuCoin is also claimed to be capable of performing 10,000 transactions per second.

The reputation is based on the miner, not the coin or token itself.

"RepuCoin is different as it defines a miner's power by its 'reputation', as a function of its work integrated over the time of the entire blockchain, rather than through instantaneous computing power which can be obtained quickly," Monash wrote in a statement on Thursday.

Essentially, when a miner goes outside the boundaries of system specification, RepuCoin lowers the miner's reputation to prevent any malicious activity "without significant consequences".

"But make no mistake, this is not about subjective reputation in the sense of social networks; it is about physics," Professor Paulo Esteves-Verissimo from the University of Luxembourg, who was also involved in the proof of concept, said. "Voting power takes time to build, accumulating through consistent and honest mining work. It's like charging a battery before being able to use it.

"RepuCoin provides an elegant solution to a problem that many thought was insoluble. Existing systems always linked computational power to voting power. We separated them and now someone could join RepuCoin with 99 percent of the total computing power and they still wouldn't be able to attack it."

The announcement from the Australian university follows the federal government's Digital Transformation Agency (DTA) recently handing out advice to those getting lost in the buzz of blockchain.

"It is the DTA's current position that blockchain is an emerging technology worthy of ongoing observation. However, without standardisation and additional work, for many uses of blockchain, there are currently other mature technologies that may be more suitable for immediate use," is the agency's official position.

Addressing Senate Estimates in October, DTA chief digital officer Peter Alexander dunked on its use, adding to the above that "for every use of blockchain you would consider today, there is a better technology -- alternate databases, secure connections, standardised API engagement".

"Blockchain: Interesting technology but early on in its development, it's kind of at the top of a hype cycle," he said.

The government entity has even published a questionnaire for organisations to self-evaluate before bothering with something that can just be stored in a secure database.


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