# Overview

On-chain and off-chain applications connected to gaming, lottery, and sampling rely heavily on entropy. It could be a dynamic NFT mint, loot boxes, random opponent pairing, randomized spawn environments, an in-game item upgrade, a lottery, or a selection of contributors for an IDO. Randomness in applications is supposed to ensure fair and equal possibilities for participants. Random Number Generation (RNG) has to be unbiased and tamper-proof to be deemed fair. In other words, the process can't be manipulated by any participant, and the randomness that was generated is immutably and publicly verifiable thereafter.

Blockchain-based verifiable random functions (VRFs) enable the generation of numbers that are as good as random (pseudorandom) and can be (publicly) verified on-chain. Pseudorandomness guarantees both unpredictability and fairness in RNG, whereas tamper-proofness is demonstrated by via transparency inherent to their immutable on-chain records and verifiability.

### Supra dVRF

Supra’s dVRF can provide the exact properties required for a random number generator (RNG) to be fair with tamper-proof, unbiased, and cryptographically verifiable random numbers to be employed by smart contracts.

**Unbiased and Unpredictable** - The threshold signature of the nonce, client-provided input, and blockhash of the transaction that requests the randomness (which is unknown at the time of request) is used as the seed for the RNG function**.**

**Tamper Proof and Verifiable** - Cryptographic proof will be provided to verify that random numbers were generated and communicated with the highest fidelity.

**Supra VRF Architecture**

<figure><img src="https://content.gitbook.com/content/MZSdfFKcQCRdzJRAvpRn/blobs/4gIc9XswOXvTws7fNgS3/SupraDVRF.png" alt=""><figcaption><p>Supra decentralised VRF (dVRF) architecture overview</p></figcaption></figure>

Available Networks

Please refer to the [*Available Networks*](#available-networks) *page* for the networks supported.

### Accessing Supra dVRF

Supra dVRF  operates on a customer-controlled wallet subscription model where your registered wallet address serves as the main reference for access permissions and callback transaction gas fee payments.

Please refer to the [VRF Developer Guide](https://docs.supra.com/dvrf/build-supra-l1/v2-guide) for a step-by-step explanation of how to consume Supra’s dVRF services.

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Important: Please make sure you read and understand [Terms of Use](https://supra.com/terms-of-use/) before start using Supra products and services.
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