Blockchain a Digitálne meny 

V Kocke


David Stancel



  1. Vznik elektronických mien Bitcoinu a Blockchainu
  2. Princípy fungovania blockchain technológií 
  3. Trendy, projekty, vízie a výzvy







  • Founder @ Blockchain Slovakia
  • exCTO @ Fumbi, exIT Auditor @PwC
  • Advisor @ Vacuumlabs, Aaro Capital
  • Lecturer @ STU FIIT, EUBA FHI
  • Author of Coinstory:


About me



... má svoje korene v rôznych myšlienkových smeroch:


teória hier, kryptografia, hackerská kultúra, open source hnutie, a libertarianizmus .. 




  • Vzácnosť - 21 M mincí 
  • Delitelnosť - 100 000 000 "halierov" --> satoshi
  • Overitelnosť - verejná databáza, postavená na kryptografii, open source
  • Prenosnosť - stačí privátny kľúč
  • Zameniteľnosť (Fungibility)?




Princípy fungovania Blockchain technológií

What is Blockchain?

A tamper-proof, shared digital append-only ledger that records transactions grouped into blocks in a decentralized peer-to-peer network. The permanent recording of transactions in the Blockchain stores permanently the history of asset exchanges that take place between the peers.

Updating the ledger (usually) requires solving Byzantine Agreements (hash) with economically incentivized participation, secured by cryptography

Blockchain I.

Blockchain II.

1. Nová tranzakcia je odoslaná do siete

2. Každý uzol v sieti zbiera tranzakcie do bloku

3. Pri každom kole /bloku/ náhodne vybraný uzol získa právo určiť "pravdu"

4. Ďalšie uzle v sieti akceptujú blok iba za definovaných podmienok (ak má validné podpisy a tranzakcie)

5. Akceptáciu bloku vyjadrujú zahrnutím jeho hashu do svojich ďalších blokov

Blockchain III.

Blockchain IV.

Blockchain IV.

Blockchain V.


Key management

Institutional - Ledger Vault III

Smart Contracts

  • Cutting edge, untested
  • 10 x more buggy code
  • Different logic than SW on centralized machines
  • Potentially unchangeable
  • Different platforms, limited interoperability
  • Ethereum seems to be so far the winner


Trendy, projekty, vízie

Zmena paradigmy?

ICOs in 2017

ICOs in 2018


Non-fungible tokens



In the fourth quarter of 2020 and first quarter of 2021, the gaming industry had two of its largest-ever initial public offerings (IPOs) in Unity Technologies and Roblox Corporation, both of which wrapped their corporate histories and ambitions in Metaverse-related narratives.

Metaverse II.

Start in the 1970s with text-based virtual worlds known as Multi-User Dungeons. MUDs were effectively a software-based version of the role-playing game Dungeons & Dragons.

Using text-based commands that resembled human languages, players could interact with one another, explore a fictional world populated by non-playable characters and monsters, attain power-ups and knowledge, and eventually retrieve a magical chalice, defeat an evil wizard, or rescue a princess

Metaverse III.

Great leap came in 1986 with the release of the Commodore 64 online game Habitat, which was published by Lucasfilm, the production company founded by Star Wars creator George Lucas.


Habitat was described as “a multi-participant online virtual environment” and, in a reference to Gibson’s novel Neuromancer, “a cyberspace.”


“Citizens” of Habitat were in charge of the laws and expectations of their virtual world, and had to barter with each other for necessary resources and avoid being robbed or killed for their wares. This challenge led to periods of chaos, after which new rules, regulations, and authorities were established by the player community to maintain order

Metaverse IV.

The 1990s saw no major “proto-Metaverse” games, but advances continued. That decade, millions of consumers took part in the first isometric 3D (also known as 2.5D) virtual worlds, which gave the illusion of three-dimensional space, but only allowed users to move across two axes.


Not long after, full 3D virtual worlds emerged. A number of games, such as 1994’s Web World and 1995’s Activeworlds, also empowered users to collaboratively build a visible virtual space in real time, rather than through asynchronous commands and votes

Metaverse V.

2007 - stock exchange was launched in Second Life
with the aim of helping Second Life–based companies raise capital using the platform’s Linden Dollars currency.


Throughout the 2010s, bands of users collaborated in Minecraft to build cities as large as Los Angeles—roughly 500 square miles.


One video game streamer, Aztter, constructed a stunning cyberpunk city out of an estimated 370 million Minecraft blocks, having worked an average of 16 hours per day for a year.


Metaverse VI.

Fortnite’s social experiences -- its famous 2020 concert with Travis Scott. In that case, “players” converged on a much smaller portion of the map.


The title’s standard cap of 100 players per instance was halved, while many items and actions, such as building, are disabled, thereby further reducing the workload. While Epic Games can rightly say that more than 12.5 million people attended this live concert, these attendees were split across 250,000 separate copies (meaning, they watched 250,000 versions of Scott) of the event that didn’t even start at the same time. 


EVE Online stands apart from games like World of Warcraft and Fortnite because all users are part of one singular and persistent realm.

Metaverse VII.

Over the course of an average day in 2021, over 350 million people participated in a battle royale game—just one genre of high CCU game—and billions were able to do so. In 2016, only 350 million people in the world owned the equipment needed to render a rich 3D virtual world. At its peak in 2021, Roblox had 225 million monthly users


Roblox and Minecraft are among the most popular games in the world, their reach is modest when considered in the broadest terms. These two supposed titans have 30–55 million daily active users, a fraction of the global internet population of 4.5–5 billion. In effect, they are still at the ICQ stage of virtual words

Metaverse VIII.

Concurrency is one of the foundational problems for the Metaverse, and for a fundamental reason: it leads to exponential increases in how much data must be processed, rendered, and synchronized per unit of time.


Microsfot Flight Simulator -the most realistic and expansive consumer-grade simulation in history. Its map is over 500,000,000 square kilometers—just like the “real” planet earth—and includes two trillion uniquely rendered trees (not two trillion copy-and-pasted trees, or two trillion trees made up of a few dozen varieties), 1.5 billion buildings, and nearly every road, mountain, city, and airport across the world.

Metaverse IX.

Microsfot Flight Simulator -the most realistic and expansive consumer-grade simulation in history. Its map is over 500,000,000 square kilometers—just like the “real” planet earth—and includes two trillion uniquely rendered trees (not two trillion copy-and-pasted trees, or two trillion trees made up of a few dozen varieties), 1.5 billion buildings, and nearly every road, mountain, city, and airport across the world.


Microsoft Flight Simulator aspires for every town to not just differ from one another, but to exist as they do in real life. And it doesn’t want to store 100 types of clouds and then tell a device which cloud to render and with what coloring; rather, it wants to say exactly what that cloud should look like.

Metaverse X.

By the end of 2021, Adopt Me!’s virtual world had been visited more than 30 billion times—more than fifteen times the average number of global tourism visits in 2019.


Furthermore, developers on Roblox, many of whom are also small teams with fewer than 30 members, have received more than $1 billion in payments from the platform.


By the end of 2021, Roblox had become the most valuable gaming company outside of China, worth nearly 50% more than storied gaming giants Activision Blizzard and Nintendo.

What is the role of NFTs in all this?

1. The Streaming Book  by Matthew Ball, freely online


2. The Metaverse Book, and Blog by Matthew Ball


3. Virtual Economy by L'Atelier



Metaverse sources

Security Token Offerings


DeFi vs. TradFi

Stable Coins 

Stable Coins II

Stablecoins Market 

Key components - Cosmos

Key components -  Polkadot

Tokenized BTC

Smart Contracts Platform

  • First, ETH is turned into “wrapped ETH” (WETH), which is simply an ERC20 wrapping around ETH. This “tokenizes” ETH so it can be used like any other ERC20 token.

  • Next, WETH is turned into “pooled ETH” (PETH), which means it joins a large pool of Ethereum that is the collateral for all Dai created.

  • Once you have PETH, you can create a “collateralized debt position” (CDP), which locks up your PETH and allows you to draw Dai against your collateral, which is PETH.

    As you draw out Dai, the ratio of debt in the CDP increases. There is a debt limit that sets a maximum amount of Dai you can draw against your CDP.

    Once you have Dai, you can spend or trade it freely like any other ERC20 token.

DAI  - How


  • You need a loan, and have an asset (ETH) to use as collateral for your loan
  • You believe ETH is going up in value. You can use your CDP to buy ETH on margin — you lock up your ETH in a CDP, draw Dai against it, use the Dai to buy more ETH on an exchange, and then use that ETH to further increase the size of your CDP.
    --> without any third-party or centralized authority

  • The demand for Dai drives the price above $1 USD. When this occurs, you can create Dai then immediately sell it on an exchange for greater than $1 USD. This is essentially free money, and is one of the mechanisms the Maker system uses to keep Dai pegged to $1 USD. Dai being worth over $1 USD encourages more Dai to be created.

DAI - Why?


  • If Dai < $1 USD, CDP owners can pay down their debt at a cheaper price! 

  • fe. CDP with $1000 in ETH --> draw out 500 Dai
    to close the position --> pay back 500 Dai (paying debt destroys Dai).

  • If Dai < $1 USD, then buy cheaper DAI (fe 0.99 USD) --> pay off debt with a 1% discount == free money — $500 loan (500 Dai) --> 500 Dai for $495 (0.99 * 500 = 495, a 1% discount)
  • --> demand for Dai increases its price, until it approaches $1 USD.
    If Dai stays below $1, CDP owners continue to pay down debt and remove Dai from the system.

  • --> When Dai goes above $1 USD, Dai is created to feed the demand. It is this push and pull, creation and destruction, supply and demand which ensures that Dai always matches the $1 USD peg.

DAI - Peg Mechanism

Synthetic Stocks

Web 3.0 Stack

Web 2.0 Stack

Web 3.0 Stack

Total Value Locked in DeFi on the Ethereum Blockchain from August 2017 to April 2022

  • Tax/ Legal Treatment of Stocks vs Crypto stocks?
  • Who is responsible for the undesired app behaviour?
  • Is it really immutable?
  • Using DeFi via UI vs. Raw transactions ––> no signed disclaimer ––> different legal implications?
  • KYC / AML ?
  • Real-World Assets as Crypto Loan Collateral
  • MiCA - NFT and DeFi Out of Scope

Challenges in DeFi 






Blockchain & Digitalne Meny v Kocke NBS 2024

By David Stancel

Blockchain & Digitalne Meny v Kocke NBS 2024


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