SkyPirl Blockchain
  • SkyPirl (Pirl)
    • Docs.Pirl.io
    • About SkyPirl (Pirl)
    • Mission
    • Create SkyPirl 2.0 wallet
    • Restore wallet with secret 12 phrase
    • How to be a Nominator
    • SkyPirl coin specifications
    • Run a validator
    • How to unbound fund
    • How payout works
    • How to vote for Council
    • How to set identity
    • SLASHES
    • Refund of slashed
    • COIN SPECIFICATION
    • Governance and Treasury
    • Telemetry
    • List of wallet addresses not working
    • Spending from the treasury and Burn
    • Mint coins and transfer coins to the treasury
      • Treasury2
    • Burn 2
    • Source Code
    • List of wallets holding coins of burned wallets with PIRL balance at block 3939000
  • About SkyPirl (Pirl)
  • Mission
  • PIRLmeet
    • About Room-House.com
    • Free Trial
    • CINEMA
    • Microphone On-Off
    • Screen Sharing
      • Share—or don't share your audio
      • Video recording tutorial + camera + mp4 video download
    • Hands Up
    • Change the ringtone when giving a raise of hand
    • Stream MP4 videos
    • Stream mp4 video on Firefox browser
    • Cabinet Lock
      • Cabinet Lock account
      • Normal-Demo
      • How can I cabinet lock and keep strangers from entering the room?
      • How can I add people to the room when the room is locked?
    • Text chat
      • Room chat
      • Cabinetlock Chat
      • private chat per video
    • Connect Pirl wallet to Room-House
    • Change cover photo
    • Video title name
    • Setting up you own PIRLmeet
    • How to download videos on youtube, Facebook and convert to mp4 files
    • Use camera beautification App when livestream
    • Room-House can create meetings that last 24/7 and 365 days a year.
    • How does PIRLmeet secure products?
    • Get Pirl coin when playing videos on PIRLmeet
    • Picture
    • OBS Studio
      • Download
      • Screen sharing and front camera
      • Stream video from R-H to Youtube
      • Stream games
      • Stream Video and Record Video and download videos
      • Good quality video settings
      • Edit the frame and choose the recording frame
    • Source Code
  • Game
    • Room-House.com and games
    • Slot Machine
      • Connect the slot machine to the SkyPirl Light Wallet.
      • Connect Room-House.com to the slot machine
  • SkyPirl Light Wallet
  • PIRL Decentralized Charity Foundation (SkyPirl)
  • SkyPirl Community
  • Apps for Android and IOS (PWA)
    • Android
    • Iphone (IOS)
    • Computer-Windows-PC
  • Business Paradigm R-H
    • Use SkyPirl coin to pay in Room-House.com
  • Roadmap
  • Core Team
  • xTer . Technology
    • About xTER SafeContainer
    • xTer Ecosystem
    • xTer SkyPirl
    • xTer Room-House
      • How to Room-House
    • xTer Room-House Plus
      • How to xTer room-House plus
    • xTer TrueAD
    • xTer SmartFilter
  • White Paper
  • Blog
    • News
      • ------What is Web 1.0, 2.0, 3.0?------
      • The world's first decentralized audio chat room Room-House
      • What's so special about decentralized audio chat rooms?
      • Features that make Room-House.com decentralized chat rooms competitive with giants
      • Ever heard of Decentralized Charity Fund?
      • What is online meeting? 4 most effective online conferencing solutions
      • What is online meeting? Is it easy or difficult to organize?
      • What is the standard of a professional online meeting room?
      • History of the world's first online meeting software
      • Decentralized Application Room-House.com (Daap)
      • In what year was the internet born? And the birth of the project SkyPirl
      • Cooperation between Room-House and Russian State Social University
      • Building SkyPirl Decentralized Internet in Space
      • Data collection is a huge industry that operates in the dark
      • Free and easy decentralized internet for everyone to use
      • What is Pirl (PIRL) ? Community Based Project Pioneering in Introducing Masternode Technology
      • PirlGuard — Innovative Solution against 51% Attacks
      • ETC and PirlGuard Cybersecurity Plan
      • PirlChat messenger release
      • Overview of PirlChat 0.5.1–0.6 Beta Versions
      • Decentralized blockchain messengers
      • PirlChat messenger version 1.0.4 released
      • What is Pirl 2.0 and what changes will come to the Pirl network
      • The Pirl project announced the launch of its own exchange
      • PIRL’s Content Masternodes Are Almost Out: What You Need to Know
      • PIRL Masternodes and DApps Overview
      • SkyPirl (PIRL) Decentralized Charity Foundation
      • Thanks to PirlGuard, Callisto is protected against 51% attacks
      • What is SkyPirl(PIRL) project?
      • Here is the sci-fi story of the decentralized social network PIRL:
      • What is Callisto-Pirl.com project?
      • Here is the legend of the multi-planetary decentralized internet space station PIRL:
      • PIRL decentralized social network has the following key differences:
      • The SM feature of the decentralized social network PIRL seems to be an interesting secret.
      • SkyPirl(PIRL) is designed to attract investors with attractive features:
      • SkyPirl project does not sell ICO (Initial Coin Offering) or not raise funds for the following reaso
      • Merry Christmas and a Happy New Year! SkyPirl Callisto-Pirl.com
      • SkyPirl Project Merry Christmas Story:
      • Happy New Year! SkyPirl Callisto-Pirl.com
      • Here's the story of the SkyPirl Mars Exploration Project:
      • Multiplanetary Billionaire
      • Lost in space
      • The Last Space Train
      • The future of society: Polarization of rich and poor in the 4.0 revolution
      • Callisto-Pirl.com Civil War
      • Callisto-Pirl.com Civil War 2
      • Callisto-Pirl.com Civil War 3
      • Callisto-Pirl.com Civil War 4
      • Callisto-Pirl.com Civil War 5
      • Callisto-Pirl.com Civil War 6
      • Callisto-Pirl.com Civil War 7
      • Callisto-Pirl.com Civil War 8
      • Callisto-Pirl.com Civil War 9
      • Callisto-Pirl.com Civil War 10
      • Callisto-Pirl.com Civil War 11
      • Callisto-Pirl.com Civil War 12
      • Page
    • Technical
      • What is Bitcoin? How are Bitcoins created?
      • Export Your Private Key from Third-Party Wallets
      • What Is a Stablecoin?
      • What Is Wrapped Bitcoin?
      • 7 Ways to Generate Passive Income With Crypto
      • What is a decentralized social network?
      • How many Bitcoins can be mined in a day?
      • How many Bitcoins are there in the world?
      • What is a decentralized exchange? different from centralized floor?
      • What is Staking? 5 things to note when investing in Staking
      • What Are Blockchain Bridges?
      • Compare Hot Wallet and Cold Wallet, which one should you use?
      • What is NFT?
      • Building a Decentralized Internet in Space
      • Web 3.0 Paradox
      • Controversy about the future of the Internet
      • The metaverse virtual universe could revolutionize the Internet
      • 'Blockchain is the most influential technology since the Internet'
      • Web3 - Expectations for the Decentralized Internet
      • What is Dapp? The concept of Dapp and their classification
      • How Decentralized Web Browsers Give You Unsurpassed Privacy
      • Is Web 3.0 being hyped?
      • What are Nodes? Types of Nodes in Blockchain
      • Blockchain can be hacked or not?
      • What is Private Key and Public Key in Bitcoin?
      • What is a Nonce in Blockchain?
      • What is Decentralized Autonomous Cooperative (DAC)?
      • What is Genesis Block?
      • What is Web3? Explaining the Decentralized Internet of the Future
      • Z-Consensus , Callisto NetWork
      • DEX223 Explanation
      • CLOIPs
        • CLOIPs1
        • CLOIPs2
        • CLOIPs3
        • CLOIPs4
      • Skuld Hard Fork: Transforming Callisto Network with Dynamic Monetary Policy
      • Dex223: Decentralized exchange for ERC-223 & ERC-20 tokens!
      • What is SAVI Token?
    • Pi NetWork
      • Pi NetWork ( English )
        • Pi Network (PI) Mining Step by Step Guide
        • How to Create a Pi Wallet
        • How to KYC Pi Network 100% Success (2023)
        • Pi Network Security Circle: How to Add Users to Security Circle?
        • How to Migrate Your Mining Pi Coin to Mainnet in 8 Steps (See Video)
        • Why Pi Network can become the most active existence of mobile smart cryptocurrency?
        • FAQ? (FAQ)
      • Pi NetWork ( Tiếng Việt)
        • Pi NetWork là gì?
        • Cách KYC Pi Network 100% thành công (2023)
        • Vòng tròn bảo mật là gì?
        • Hướng dẫn tạo ví Pi Network
        • Cách Đào Pi Trên Điện Thoại
        • Cài đặt tên như thế nào là đúng trong Pi Network
        • Bạn cần xác nhận ngay VÍ PI THẬT để chuẩn bị chuyển SỐ PI XỊN vào ví pi sau khi hoàn thành KYC.
        • Hướng dẫn cách rút chuyển Pi về Ví Mainnet
        • Cách tăng tốc độ Đào Pi Network
        • Tại sao Pi Network có thể trở thành sự tồn tại tích cực nhất của tiền điện tử thông minh di động?
        • Hỏi đáp (FAQ)
    • Việt Nam
      • Pirl (PIRL) Là Gì ? Dự Án Dựa Trên Cộng Đồng Đi Tiên Phong Trong Việc Giới Thiệu Công Nghệ Masternod
      • Giới thiệu về SkyPirl (Pirl)
      • Sứ Mệnh Pirl2.0
      • Phần mềm Room-House.com là gì
      • Giới thiệu về Room-House.com
      • Room-House có thể tạo các cuộc họp kéo dài 24/7 và 365 ngày một năm.
      • Room-House.com bảo mật sản phẩm như thế nào?
      • Giới thiệu về xTER SafeContainer
      • Kế hoạch an ninh mạng của ETC và PirlGuard
      • Quỹ từ thiện phi tập trung Pirl
      • Phát hành trình nhắn tin PirlChat
      • Tổng quan về các phiên bản Beta của PirlChat 0.5.1–0.6
      • Trình nhắn tin chuỗi khối phi tập trung
      • PirlChat messenger phiên bản 1.0.4 được phát hành
      • Pirl 2.0 là gì và những thay đổi nào sẽ đến với mạng Pirl
      • Dự án Pirl đã công bố ra mắt sàn giao dịch của riêng mình
      • Masternode nội dung của PIRL sắp hết: Những điều bạn cần biết
      • Tổng quan về PIRL Masternodes và DApps
      • Xây dựng Internet phi tập trung SkyPirl trong không gian
      • Nhờ PirlGuard, Callisto được bảo vệ chống lại các cuộc tấn công 51%
    • Charity
      • Децентрализованный благотворительный фонд PIRL
      • PIRL 去中心化慈善基金会
      • PIRL 分散型慈善財団
      • Yayasan Amal Terdesentralisasi PIRL
      • PIRL विकेंद्रीकृत चैरिटी फाउंडेशन
      • Fundación Benéfica Descentralizada PIRL
      • Pirl المؤسسة الخيرية اللامركزية
      • קרן צדקה מבוזרת של PIRL
      • PIRL 분산형 자선 재단
      • PIRL Dezentrale Wohltätigkeitsstiftung
      • Ang mga desentralisadong charity fund Pirl
      • ມູນນິທິການກຸສົນ PIRL Decentralized
      • PIRL Decentralized caritas Foundation
      • มูลนิธิการกุศล Pirl กระจายอำนาจ
      • PIRL төвлөрсөн бус буяны сан
      • PIRL Weqfa Xêrxwazî ​​ya Nenavendî
      • Fundacja Dobroczynności Zdecentralizowanej PIRL
      • PIRL Gedesentraliseerde Liefdadigheidstigting
      • PIRL Adɔe Fapem a Wɔde Di Dwuma wɔ Decentralized
      • Fondacioni i Decentralizuar i Bamirësisë PIRL
      • PIRL ያልተማከለ የበጎ አድራጎት ድርጅት
      • PIRL ապակենտրոնացված բարեգործական հիմնադրամ
      • PIRL Mərkəzləşdirilməmiş Xeyriyyə Fondu
      • بنیاد خیریه غیرمتمرکز PIRL
      • Pirl বিকেন্দ্রীভূত দাতব্য তহবিল
      • PIRL Ongintzazko Fundazio Deszentralizatua
      • Дэцэнтралізаваны дабрачынны фонд PIRL
      • Pirl Decentralizovani dobrotvorni fondovi
      • Fundação de Caridade Descentralizada PIRL
      • Децентрализирана благотворителна фондация PIRL
      • Fundació Solidària Descentralitzada PIRL
      • Ang Pirl Decentralized Charity Fund
      • PIRL Fundazione di Carità Decentralizata
      • Decentralizirana dobrotvorna zaklada PIRL
      • Decentraliserede velgørenhedsfonde Pirl
      • PIRL detsentraliseeritud heategevusfond
      • PIRL Dɔmenyohabɔbɔ si Woɖo Ðe Dɔwɔƒewo
      • Stèidheachd Carthannais Sgaoilte PIRL
      • Fundación Benéfica Descentralizada PIRL
      • Ekitongole ky’obwannakyewa ekya PIRL Decentralized Charity Foundation
      • PIRL დეცენტრალიზებული საქველმოქმედო ფონდი
      • Fundación Caridad Descentralizada PIRL rehegua
      • PIRL વિકેન્દ્રિત ચેરિટી ફાઉન્ડેશન
      • PIRL Stichting Gedecentraliseerde Goede Doelen
      • Fondasyon Charite Desantralize PIRL
      • Gidauniyar Sadaka Mai Rarraba PIRL
      • PIRL Decentralizált Jótékonysági Alapítvány
      • Αποκεντρωμένο Φιλανθρωπικό Ίδρυμα PIRL
      • PIRL dreifð góðgerðarstofnun
      • PIRL Akwụsịghị Charity Foundation
      • Fondúireacht Carthanachta Díláraithe PIRL
      • PIRL Fondazione di beneficenza decentrata
      • PIRL ವಿಕೇಂದ್ರೀಕೃತ ಚಾರಿಟಿ ಫೌಂಡೇಶನ್
      • PIRL орталықтандырылмаған қайырымдылық қоры
      • PIRL មូលនិធិសប្បុរសធម៌វិមជ្ឈការ
      • PIRL Kwegereza abaturage ibikorwa byubugiraneza
      • PIRL Weqfa Xêrxwazî ​​ya Nenavendî
      • دامەزراوەی خێرخوازی لامەرکەزی PIRL
      • PIRL борбордон ажыратылган кайрымдуулук фонду
      • PIRL decentralizētais labdarības fonds
      • Fondation de Charité Décentralisée ya PIRL
      • PIRL decentralizuotas labdaros fondas
      • PIRL dezentraliséiert Charity Foundation
      • PIRL Децентрализирана добротворна фондација
      • PIRL Decentralized Charity Foundation
      • PIRL വികേന്ദ്രീകൃത ചാരിറ്റി ഫൗണ്ടേഷൻ
      • Fondazzjoni tal-Karità Deċentralizzata PIRL
      • PIRL Decentralized ပရဟိတဖောင်ဒေးရှင်း
      • Desentraliserte veldedige midler Pirl
      • PIRL विकेन्द्रीकृत चैरिटी फाउन्डेशन
      • PIRL Decentralized Charity Foundation
      • PIRL ବିକେନ୍ଦ୍ରୀକରଣ ଚାରିଟି ଫାଉଣ୍ଡେସନ୍ |
      • Faawundeeshinii Arjummaa Giddugaleessa Hin Qabne PIRL
      • PIRL غیر متمرکز خیریه بنسټ
      • Fondation caritative décentralisée PIRL
      • PIRL Hajautettu hyväntekeväisyyssäätiö
      • PIRL ਵਿਕੇਂਦਰੀਕ੍ਰਿਤ ਚੈਰਿਟੀ ਫਾਊਂਡੇਸ਼ਨ
      • PIRL Fundación Caridad Descentralizada nisqa
      • Fundația Descentralizată de Caritate PIRL
      • Decentralizované charitativní fondy Pirl
      • Децентрализована добротворна фондација Pirl
      • PIRL Aasaaska Samafalka ee Baahsan
      • Motheo wa Botho wo o Arotšwego wa PIRL
      • PIRL Decentralized Charity Foundation - Letlole la liphallelo
      • Yayasan Amal Desentralisasi PIRL
      • PIRL Wakfu wa Hisani uliogatuliwa
      • Фонди хайрияи ғайримарказии PIRL
      • PIRL பரவலாக்கப்பட்ட தொண்டு அறக்கட்டளை
      • PIRL వికేంద్రీకృత ఛారిటీ ఫౌండేషన్
      • PIRL Merkezi Olmayan Yardım Vakfı
      • Pirl Stiftelsen för decentraliserad välgörenhet
      • PIRL ዘይተማእከለ ግብረ ሰናይ ፋውንዴሽን
      • PIRL 去中心化慈善基金會
      • Децентралізований благодійний фонд PIRL
      • Pirl ڈی سینٹرلائزڈ چیریٹی فاؤنڈیشن
      • PIRL تارقاق خەير-ساخاۋەت فوندى
      • PIRL markazlashtirilmagan xayriya fondi
    • Khoa học, tâm linh và máy tính
      • SuDO Key the power of God
      • Dream, Parallel Universe
      • What is Constellation, Star?
      • If Bitcoin is considered a technology created by the "Creator", can opposing Bitcoin be considered o
      • Decentralized Universe
      • Earth's Development History: From Flat to Sphere
      • The Future of Religion and Technology
  • FAQ?
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  • Agency policy
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  • Rumhaus
    • О Room-House.com
    • Бесплатная пробная версия
    • CINEMA
    • Microphone On-Off
    • Демонстрация экрана
      • Поделитесь или не делитесь своим аудио
      • Учебное пособие по записи видео + камера + загрузка видео в формате mp4
    • Руки вверх
    • Изменить мелодию звонка при поднятии руки
    • Потоковое видео в формате MP4
    • Потоковое видео mp4 в браузере Firefox
    • Cabinet Lock
      • Cabinet Lock account
      • Как я могу «запереть шкаф» и не дать посторонним войти в комнату?
      • Как я могу добавить людей в комнату, когда комната заблокирована?
    • Подключить кошелек SkyPirl к Room-House
    • Изменить обложку
    • Название видео
    • Настройка собственного Room-House
    • Как скачать видео на ютуб, фейсбук и конвертировать в мп4 файлы
    • Используйте приложение для улучшения камеры во время прямой трансляции
    • Room-House может организовывать встречи, которые длятся 24/7 и 365 дней в году.
    • Как Room-House защищает продукты?
    • Получите монету Pirl при воспроизведении видео на Room-house
    • Source Code
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  1. FAQ?
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  3. Advanced

Randomness

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Randomness in Proof of Stake blockchains is important for a fair and unpredictable distribution of validator responsibilities. Computers are bad at random numbers because they are deterministic devices (the same input always produces the same output). What people usually call random numbers on a computer (such as in a gaming application), are pseudo-random - that is, they depend on a sufficiently random seed provided by the user or another type of oracle, like a , your , or even , from which it can generate a series of seemingly-random numbers. But given the same seed, the same sequence will always be generated.

Though, these inputs will vary based on time and space, and it would be impossible to get the same result into all the nodes of a particular blockchain around the world. If nodes get different inputs on which to build blocks, forks happen. Real-world entropy is not suitable for use as a seed for blockchain randomness.

There are two main approaches to blockchain randomness in production today: RANDAO and VRF.

Polkadot uses VRF.

VRF

A verifiable random function (VRF) is a mathematical operation that takes some input and produces a random number along with a proof of authenticity that this random number was generated by the submitter. The proof can be verified by any challenger to ensure the random number generation is valid.

The VRF used in Polkadot is roughly the same as the one used in Ouroboros Praos. Ouroboros randomness is secure for block production and works well for . Where they differ is that Polkadot's VRF does not depend on a central clock (the problem becomes - whose central clock?), rather, it depends on its own past results to determine present and future results, and it uses slot numbers as a clock emulator, estimating time.

Here's how it works in detail:

Slots are discrete units of time six seconds in length. Each slot can contain a block, but may not. Slots make up - on Polkadot, 2400 slots make one epoch, which makes epochs four hours long.

In every slot, each validator "rolls a die". They execute a function (the VRF) that takes as input the following:

  • The "secret key", a key specifically made for these die rolls.

  • An epoch randomness value, which is the hash of VRF values from the blocks in the epoch before last (N-2), so past randomness affects the current pending randomness (N).

  • The slot number.

The output is two values: a RESULT (the random value) and a PROOF (a proof that the random value was generated correctly).

The RESULT is then compared to a threshold defined in the implementation of the protocol (specifically, in the Polkadot Host). If the value is less than the threshold, then the validator who rolled this number is a viable block production candidate for that slot. The validator then attempts to create a block and submits this block into the network along with the previously obtained PROOF and RESULT. Under VRF, every validator rolls a number for themselves, checks it against a threshold, and produces a block if the random roll is under that threshold.

RANDAO is optionally augmented with VDF.

VDFs will likely be implemented through ASIC devices that need to be run separately from the other types of nodes. Although only one is enough to keep the system secure, and they will be open source and distributed at nearly no charge, running them is neither cheap nor incentivized, producing unnecessary friction for users of the blockchains opting for this method.

The astute reader will notice that due to the way this works, some slots may have no validators as block producer candidates because all validator candidates rolled too high and missed the threshold. We clarify how we resolve this issue and make sure that Polkadot block times remain near constant-time in the wiki page on .

RANDAO

An alternative method for getting randomness on-chain is the method from Ethereum. RANDAO requires each validator to prepare by performing many thousands of hashes on some seed. Validators then publish the final hash during a round and the random number is derived from every participant's entry into the game. As long as one honest validator participates, the randomness is considered secure (non-economically viable to attack).

VDFs

are computations that take a prescribed duration of time to complete, even on parallel computers. They produce unique output that can be independently and efficiently verified in a public setting. By feeding the result of RANDAO into a VDF, a delay is introduced that renders any attacker's attempt at influencing the current randomness obsolete.

Resources

- contains reasoning for choices made along with proofs

- W3F researchers discuss the randomness in Polkadot and when it is usable and under which assumptions.

consensus
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RANDAO
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Verifiable Delay Functions
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Polkadot's research on blockchain randomness and sortition
Discussion on Randomness used in Polkadot
weather station for atmospheric noise
heart rate
lava lamps
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BABE
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epochs