Facebook’s Calibra team has recently released a new research paper with a different process for Byzantine fault tolerance (BFT) testing called “Twins.” The new methodology invented by the Calibra team is believed to be a lightweight method of BFT implementation. The research paper also highlighted that despite extensive study towards BFT systems for over two decades, there aren’t any principal strategies for testing BFT implementations.
The new methodology invented by Calibra runs two instances of the same node with the same identity to mimic Byzantine behavior. The research paper also noted that its Twins methodology allows the operator to create systematic Byzantine attack scenarios, scale them under control, and then look for desired protocol properties.
What is Byzantine Fault Tolerance?
Byzantine Fault Tolerance is a concept that was derived from an academic paper from 1982 published by Leslie Lamport, Robert Shostak, and Marshall Pease. It is a metaphor derived from a scenario where a group of Byzantine Generals have surrounded a castle and are ready to attack. In order to successfully execute the attack, each one of them must carry out simultaneously, however, there is a traitor amongst them which makes it difficult for them to execute the attack in a union.
In the case of a blockchain network, the Byzantine Fault refers to a situation where all the players in the network are trying to coordinate among themselves to nullify the risk of malevolent parties trying to pass wrong info as in inaccurate data to disrupt the network. Bitcoin overcomes this issue through its POW mining consensus, where numerous miners input their computational power simultaneously to mine the next block.
Calibra’s BFT implementation Twins emulate several attacks on the BFT protocols and the research paper also claimed that the BFT attacks which took the community almost two decades would be possible to detect in a matter of few minutes using Twins. David Marcus, the co-creator of Calibra noted,
One of my greatest joys at work is getting to work with some of the brightest and most capable people in the industry. Here's some cutting edge work on testing BFT implementations by our mighty research team. https://t.co/kCYLBjGiJF
— David Marcus (@davidmarcus) April 23, 2020
While Twins methodology is capable of finding several Byzantine seniors, at the same time some Byzantine behavior is not detectable by the new methodology including those which do not include complete divulgence of an unusual past.
Facebook’s Libra Project Make Changes to their White Paper Again
Facebook’s nascent crypto project Libra has been in hot waters ever since its announcement last year. The whitepaper and working model of the digital currency did not impress regulators who believed Libra would disrupt the financial sovereignty of the government and the idea of a stablecoin backed by multiple fiat currencies really irked them.
Since the announcement, the Libra project has made several amendments to the whitepaper, the most recent one being a couple of weeks back where instead of launching one stablecoin backed by multiple fiats, now they are planning to launch multiple stablecoins for different markets. However, despite these changes, the regulators seemed unhappy and pointed out that these changes were not enough as they did not address the faults pointed out by them in the first place.