Blockchain – Conclusion

July 5, 2019

In this short tutorial you were introduced to several concepts of Blockchain by taking Bitcoin as a case study. The Bitcoin is the first successful implementation of blockchain. Today, the world has found applications of […]

Bitcoin – Mitigating Attacks

July 5, 2019

I will discuss three different types of probable attacks in the Bitcoin system − Race Attack As an attacker, you may send the same coin to different vendors in rapid succession, probably by using two […]

Blockchain – Privacy

July 5, 2019

As the ledger which is recording all the bitcoin transactions is made truly public, the privacy is at stake. Anybody in the world would be able to know who paid whom? The traditional banking system […]

Blockchain – Resolving Conflicts

July 5, 2019

As we have seen the Bitcoin network contains several miners. It is possible, that the two different miners solve the Proof-of-Work at the same time and thus add their blocks to the last known block […]

Blockchain – Payment Verification

July 5, 2019

Consider a case whereby as a vendor you may like to verify a certain payment made in the past. As the blockchain you are holding on your machine contains only the block headers as shown […]

Blockchain – Merkle Tree

July 5, 2019

The issue of disk space in a node is easily overcome because all transactions in a block are hashed in a Merkle Tree as shown in image − The block header now contains the hash […]

Blockchain – Incentives to Miners

July 5, 2019

As we saw in the chapter Bitcoin – Mining, a miner may be flooded with many transactions at any given period of time. The maximum size for a block is pre-defined in the system necessitating […]

Blockchain – Network & Mining

July 5, 2019

I will now summarize the steps described above; this is what happens in the network − Anybody who wants to obtain services from the third party who has advertised on the network first creates a […]

Blockchain – Proof of Work

July 5, 2019

As all transactions are time stamped, we need to implement a distributed timestamp server on a peer-to-peer network. This requires some additional implementation and that is the Proof-of-Work that I will describe now. To each […]

Blockchain – Chaining Blocks

July 5, 2019

The blocks created by various miners are chained together to form what is known as a truly distributed public ledger. Each block in the chain contains multiple messages (transactions) as seen earlier in Figure 8. […]

Bitcoin – Mining

July 5, 2019

When Bob creates a purchase request for Lisa, he does not send it to Lisa alone. Rather the request message is broadcasted on the entire network to which he is connected. Bob’s network is depicted […]

Blockchain – Hashing

July 5, 2019

One of the most important function in PKI is the hashing function. A hash function maps the data of any arbitrary size to data of fixed size. Bitcoin uses SHA-256 hash function that produces a […]

Blockchain – Public Key Cryptography

July 5, 2019

Public Key Cryptography or in short PKI is also known as asymmetric cryptography. It uses two pairs of keys – public and private. A key is a some long binary number. The public key is […]

Bitcoin – Brief History

July 5, 2019

The Bitcoin was introduced in this world by Satoshi Nakamoto through a research-style white paper entitled Bitcoin: A Peer-to-Peer Electronic Cash System in the year 2008. The Bitcoin not only solved the double-spending problem, but also offered […]

Blockchain – Double Spending

July 5, 2019

Consider a situation shown in image − As clearly seen here, Bob is tendering a $10 bill to Lisa in exchange of a book. Once the Lisa receives this physical $10 bill, there is no […]

Blockchain – Introduction

July 5, 2019

In recent years, there is a lot of buzz on Blockchain. Many have described this as a most disruptive technology of the decade. Especially, the financial markets could be the most affected ones. The technology […]

Blockchain Tutorial

July 5, 2019

A blockchain is a growing list of records, called blocks, which are linked using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data. Blockchain has been in a […]