Truebit is an outsourced computation protocol that aims to take off-chain large computation tasks such as complex smart contracts. It was primarily built to interact with Ethereum, although it doesn’t exclude it from operating with other blockchains in the future.
Truebit’s whitepaper was released in November 2017 and was co-authored by Dr. Jason Teutsh and Christian Reitwiessner under the title ‘A scalable verification solution for blockchains’. Dr. Jason Teush (Truebit founder) is a former Ethereum Lead Developer while Christian Reitwiessner led the development of Ethereum’s native programming language, Solidity.
Vitalik Buterin, one of Ethereum’s co-founders, has also shown interest in Truebit and co-authored a paper with Dr. Jason Teutsh about Interactive Coin Offerings (IICO). Truebit came as a response to the design limitations of blockchains (throughput, security model) which don’t bode well with heavy computation tasks such as advanced smart contracts. How Truebit works: Enter Truebit, whose main function is to take off-chain those computations, solve them (more on that later) and send back results to the blockchain. As such, it can be considered as a scaling solution for Ethereum. In fact, by removing the heavy tasks from Mainnet, it ensures Ethereum only focus on simple tasks, thus producing two favorable outcomes: reduction of gas fees and congestion on the blockchain
Truebit can be considered as a marketplace where Task Givers (Organized in Task Owners and Task Submitters) request computation from Solvers and Verifiers.
Solvers perform the task which then gets passed on to Verifiers who check the solution. The Verifier becomes a Challenger if he reports an error. To ensure correctness, the Verifier is properly incentivized. The whole process is called the Verification Game. By adopting the Verification Game, Truebit solves an interesting issue, namely the Verifier Dilemma, co-discovered by Jason Teush, the founder of...Truebit.
In a Proof of Work environment, miners are assigned a set of tasks to solve. In exchange for their work, they get rewarded with newly minted tokens. However, PoW protocols have a flaw in how miners are incentivized. In fact, the very first miner who solves the mathematical puzzle gets paid while the other miners must do the work gratis. This has no consequence for most transactions because the amount of verification work needed to solve the puzzle is often negligible.
However, it becomes problematic when the mathematical puzzles that need to be verified require a significant amount of resources to verify. In that scenario, certain miners could be tempted to just ‘skip’ the verification process and move on to the next puzzle where they have a chance to get financial rewards. Put differently, Ethereum lacks a scaling verification mechanism and could be subject to serious attacks.
Truebit’s native Verification Game was built with the goal to address both the redundancy miners face (multiple miners having to verify the result even if they won’t get paid) and the incentive flawed structure.