Chainlink is best known for its pioneering work around decentralized oracles, but the project’s experts have also gone expansive with work on Mixicles, meta oracles, and beyond.
The “VRF” in that stands for verifiable random function, a cryptographic primitive that can generate random numbers in verifiable and unbiasable fashion.
Why’s this important? There are no shortage of use cases in which blockchain projects could make use of randomness, but tamper-proof randomness is a tough nut to crack when it comes to actualizing it on-chain. And anything short of tamper-proof randomness can introduce big security hole for projects, Chainlink said in an announcement post:
“A security-sensitive mindset is required to create and successfully defend a smart contract against adversaries seeking to steal the funds held by that contract. Smart contract developers using randomness as a key input should also see the manipulation of that randomness as a critical risk.”
Alas, here’s where Chainlink VRF comes in.
A Powerful Tool for Devs
The key for a reliable VRF is to be unbiasable and unpredictable, which are the exact two characteristics that Chainlink’s new tool is aimed at.
“Chainlink VRF seeks to [be fair and unguessable] by delivering its randomness along with cryptographic proofs that can be verified on-chain, showing that the randomness is indeed unpredictable,” the Chainlink team said.
As for possible use cases for the solution, they’re manifold. Chainlink specifically cited “blockchain gaming, security, [and] layer-two protocols” as low-hanging fruits.
For instance, with regard to gaming industry example, Chainlink added that its new VRF capability could make “games more fun by generating challenging and unpredictable scenarios and environments, and assigning unpredictable player rewards like loot drops.”
And that’s just one hypothetical example of many possible ones. Yet when it comes to how Chainlink VRF can be used in the here and now, look no further than no-loss “lotto” savings game PoolTogether.
PoolTogether Announces Integration
PoolTogether is an Ethereum dApp in which users can buy tickets with stablecoins like Dai or USDC in order to enter weekly or daily prize pools.
However, hitherto the randomization process has been less than perfect, the game’s CEO Leighton Cusack explained in a separate announcement:
“The PoolTogether Protocol requires random numbers to select the winner of each prize. In our initial design, this randomness generation process was a manual and centralized process […] this makes it difficult for some users to fully trust PoolTogether Protocol’s ability to generate a provably fair winner.”
Accordingly, Chainlink VRF is something of an ideal solution for this predicament, which is why the PoolTogether CEO said the project would be integrating with the tool shortly.
“Incorporating Chainlink’s VRF benefits PoolTogether by providing a more reliable and provably secure form of randomness in the selection prize winners, which our users can trust,” Cusack said.
Focus on Randomness Grows
Chainlink VRF is good news for smart contract ecosystems like Ethereum’s. Indeed, Ethereum developers in particular have been deeply considering randomness tools in recent times.
For example, last year the Ethereum Foundation collaborated with Amazon’s AWS and others on a $100,000 USD hardware competition centered on verifiable delay function (VDF) tech.
The idea behind a VDF is similar to a VRF except that the former involves a delay function during its computations. Why? In order to block malicious actors from manipulating, and thus biasing, outputs.
“Verifiable delay functions uniquely tie physical time and cryptography into a promising new tool for the blockchain industry,” the Ethereum Foundation said at the time.