Introduction to the course and building foundation of blockchain and privacy

Intro to the course

Introduction to the module and building foundation of blockchain and privacy

Introduction to the module

Introduction to Privacy

Understand the nature of public and permissioned blockchains and how they work

What is a blockchain

Understand the consensus of blockchains and how blocks are linked together using proof of work

What is mining in blockchain?

A look into what privacy means on blockchains and trying to make sense of the data from the block explorers

What is privacy within blockchains

Privacy is awesome but why do we care at all ? why cant we keep the data all public and the dangers of the applications without privacy on blockchains

Why is Privacy important - Bitcoin?

Why is Privacy important - Ethereum?

privacy techniques are based on cryptographic principles, some of which are heavily affected by the advent of quantum computing, in this lesson, we will explore this concept further and see which techniques are affected and what can be done to improve upon them

Will Quantum computing break privacy?

Understanding Blockchains, Mining, and the Problem of Privacy

There are so many privacy techniques, lets take a brief look at how each of them works from a higher level, looking at Zcash, Monero, Dash, Mixers (General)

A brief look at privacy techniques in blockchains

ZCash

Moneoro

Coinjoin

Dash

Payment Channels

Stealth Address

Privacy Techniques in Various Blockchains

Implementing a rock paper scissors game

Set up the environment for using Ethereum Remix IDE

Setting up an environment for smart contract

Implement a simple rock paper scissors contract with no privacy

Writing our first smart contract

Implementing Rock Paper Scissors

Deploying the contract and playing rock paper scissor on blockchain.

Problems with current implementation

Implementing privacy on the smart contract

Implementing A Basic Rock Paper Scissors on Ethereum

A twist in rock paper scissors game

Using Randomness to give privacy to users moves

A Walkthrough of the Solution

Conclusion and wrapping up rock paper scissors game

Implementing Privacy for Rock Paper Scissors on Ethereum

Welcome to the newline guide to privacy on blockchains, In this course we are going to be looking at privacy techniques used in blockchain and implementing really cool games like _Rock, Paper, Scissors_ on Ethereum and using cryptography primitives to help us improve privacy for our own applications.

Interested about building decentralized applications?

Want to learn how to store sensitive data in public chain or database?

Want to learn how privacy focussed cryptocurrencies actually keep transactions private?

Want to know all the tools of cryptography that you can use today?

Privacy is a very important concept in blockchains, writing a smart contract is one thing, but designing the privacy aspects of your application is another, using cryptography as a toolbox can be a way to achieve privacy that can yield very good results. For example, hashes with salt has been used for a long time to store user passwords without actually knowing the user passwords and even if the security gets compromised and they are stolen, no user data can be accessed by using the hash without knowing the preimage of the hash.

Privacy is at the heart of blockchains. Blockchains such as Bitcoin and Ethereum are very public by nature, to use them for your applications, you must not put any sensitive data on them, but you have to put something so at a later date, you can prove that a supply chain holds or a product is legitimate, but how do you go about putting data on blockchains without really revealing what the data is?

In this course we'll look at the various privacy technologies and then implement a simple but nuanced game in Solidity: _Rock, Paper, Scissors_. This game will give us a hands-on lesson in creating real-world applications that handle private data on a public blockchain.

Understand Privacy on Ethereum and Build Rock, Paper, Scissors with Solidity

In this course, we'll show you how to implement privacy in your applications and build fun projects like rock paper scissors

newline's Introduction to Privacy on Ethereum

Building rock paper scissors on Ethereum using Solidity

How privacy focussed Blockchains work like ZCash, Monero, and more

How to implement rock paper scissors with complete privacy

Learn about cryptography primitives and how to use them

How to hide data within public Blockchains

When does privacy break and looking into Post-Quantum Cryptography

Before we begin our journey in the vast world of privacy, we must first go through the basics, if you are already familiar with this, its still recommended that you bear with us so we are on the same page for all fundamental concepts.

A blockchain, originally block chain, is a growing list of records, called blocks, that are linked using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree)

Thats a lot to understand, lets try to break it down a little, a blockchain is a list of blocks, blocks contain transactions which are the state changes, currency moving from one address to another. Blockchain essentially have 3 main components:

There is a lot more that Blockchain has to offer but to understand and improve privacy for blockchain based applications, we must dive deep into the fundamentals and understand the limitations of blockchain from privacy perspective and we will be looking into several blockchains and analyzing their privacy.

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Before we begin our journey in the vast world of privacy, we must first go through the basics, if you are already familiar with this, its still recommended that you bear with us so we are on the same page for all fundamental concepts.

What is a blockchain?

[According to Wikipedia](https://en.wikipedia.org/wiki/Blockchain):

> A blockchain, originally block chain, is a growing list of records, called blocks, that are linked using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree)

Thats a lot to understand, lets try to break it down a little, a blockchain is a list of blocks, blocks contain transactions which are the state changes, currency moving from one address to another. Blockchain essentially have 3 main components:

1.  Peer to peer network
    a peer to peer network is formed between peers who have the equal privileges and share all the data between each other using a gossip protocol. In this kind of network, every node can talk to every other node and nodes can drop out and new nodes can join in without any authorization.
2.  Consensus mechanism
    Having the peer-to-peer (p2p) network is great but without having a centralized server, how do these nodes come to an agreement? The answer is consensus mechanism, a consensus mechanism is a way by which these nodes can reach an agreement, consensus mechanisms have existed before the era of blockchain and have been widely used in distributed systems, such as [Paxos](https://en.wikipedia.org/wiki/Paxos_(computer_science)) and [Raft](https://en.wikipedia.org/wiki/Raft_(computer_science)), Bitcoin used a new consensus mechanism called Proof of Work (PoW), the idea was simple, if you can prove that you have done some computation before anyone else, you will be rewarded and consensus is achieved by validating the computation. We will talk about this more in the next lesson!
3.  Cryptography
    Blockchain relies heavily on cryptography such as Hashes, Merkle trees, digital signatures, public key cryptography and more, we will walk through each of these in the Cryptography module.

There is a lot more that Blockchain has to offer but to understand and improve privacy for blockchain based applications, we must dive deep into the fundamentals and understand the limitations of blockchain from privacy perspective and we will be looking into several blockchains and analyzing their privacy.
