How It Works
Understanding the cryptographic technology that ensures fair and verifiable random selections
What is VRF?
VRF (Verifiable Random Function) is a cryptographic primitive that provides publicly verifiable proof that a random output was correctly computed from a given input. It combines the security of digital signatures with the unpredictability of random number generation.
The Selection Process
Campaign Initialization
BetaFair creates a new campaign and generates a unique VRF seed. This seed is a random string that serves as the foundation for the selection process. The seed is published before any participants join.
- Unique seed generated for each campaign
- Published transparently before selection
- Cannot be changed once published
Participant Registration
As users participate in the campaign, they are added to the token map. Each participant gets a unique identifier and their entry is recorded in the public token map that will be used for the VRF selection.
- Each participant gets a unique token ID
- Token map is built transparently
- All eligible participants are included
VRF Computation
When the campaign ends, BetaFair's system uses the VRF private key to compute a cryptographic proof. This proof combines the seed, token map, and private key to generate a deterministic random value.
- Private key creates cryptographic proof
- Combines seed + token map + private key
- Generates verifiable random output
Winner Selection
The VRF output is used to deterministically select a winner from the token map. The random value is mapped to an index in the participant list, ensuring a fair selection that cannot be predicted or manipulated.
- Random value maps to participant index
- Selection is deterministic and fair
- Cannot be predicted beforehand
Public Verification
The seed, token map, and public key are published. Anyone can use VRF360 to independently verify that the announced winner matches the VRF computation result, ensuring complete transparency.
- All parameters published openly
- Anyone can verify the result
- Mathematical proof of fairness
Key Principles
Cryptographic Security
VRF uses advanced cryptography to ensure that selections cannot be manipulated. The private key is required to generate the proof, but anyone can verify it using the public key.
Deterministic Output
The same inputs always produce the same output. This means the selection result is predetermined once the parameters are set, ensuring no one can change the outcome.
Public Verifiability
Anyone can verify the selection using VRF360. You don't need to trust BetaFair—you can independently confirm the result using publicly available parameters.
Tamper Evidence
Any attempt to manipulate the seed, token map, or result will be immediately detectable. The cryptographic proof ensures the integrity of the entire process.
Why VRF Matters
Traditional random selection methods rely on trust. You have to trust that the organization conducting the selection is being fair and hasn't rigged the process in favor of certain participants.
With VRF, trust is replaced by mathematical proof. The cryptographic properties of VRF ensure that:
- The result cannot be predicted before the selection
- The result cannot be changed after parameters are published
- Anyone can independently verify the result
- Any tampering is immediately detectable
This level of transparency and verifiability is what makes BetaFair campaigns truly fair and trustworthy.
Ready to Verify a Selection?
See VRF in action by verifying a BetaFair campaign selection