Blockchain is one of the most innovative discoveries of the past century.
The first cryptocurrency, Bitcoin, was proposed in 2008 by Satoshi Nakamoto with a white paper.
How Blockchain and Cryptocurrency works.Waleed Ahmed
A blockchain is a way of storing data so that cannot be changed anymore. This is called immutability and a very useful feature when dealing with very important data like bank records or transactions.
This presentation will teach you the simplest methodology of how blockchain works.
Blockchain And Cryptocurrency : How Blockchain And Cryptocurrency Relate To E...Blockchain Council
Blockchain Council is a renowned platform providing all the certification and Blockchain courses that will help you make an established career in this field.
With the recent crypto bubble engulfing the world, you would have come across two prominent words: Blockchain and Cryptocurrency. Well, when it comes to origin and development then cryptocurrency marks the growth of Blockchain technology.
Decentralized: Blockchain & Cryptocurrency Laws in CanadaAlexander Davis
Blockchain technologies and cryptocurrencies are becoming more commonplace in Canada. This presentation presents an informational-purposes only overview of some of the laws governing them.
How Blockchain Is Different From Cryptocurrency?Endive Software
Yes, there are some differences, but at the core Blockchain and Cryptocurrency are interconnected. Bitcoin (Cryptocurrency) is the first and most successful application of Blockchain. Initially, they were used interchangeably, but with advancement, some differences can be noticed.
How Blockchain and Cryptocurrency works.Waleed Ahmed
A blockchain is a way of storing data so that cannot be changed anymore. This is called immutability and a very useful feature when dealing with very important data like bank records or transactions.
This presentation will teach you the simplest methodology of how blockchain works.
Blockchain And Cryptocurrency : How Blockchain And Cryptocurrency Relate To E...Blockchain Council
Blockchain Council is a renowned platform providing all the certification and Blockchain courses that will help you make an established career in this field.
With the recent crypto bubble engulfing the world, you would have come across two prominent words: Blockchain and Cryptocurrency. Well, when it comes to origin and development then cryptocurrency marks the growth of Blockchain technology.
Decentralized: Blockchain & Cryptocurrency Laws in CanadaAlexander Davis
Blockchain technologies and cryptocurrencies are becoming more commonplace in Canada. This presentation presents an informational-purposes only overview of some of the laws governing them.
How Blockchain Is Different From Cryptocurrency?Endive Software
Yes, there are some differences, but at the core Blockchain and Cryptocurrency are interconnected. Bitcoin (Cryptocurrency) is the first and most successful application of Blockchain. Initially, they were used interchangeably, but with advancement, some differences can be noticed.
Block chain and Bitcoin. A blockchain is a data structure that makes it possible to create a digital ledger of transactions and share it among a distributed network of computers.
There are many cryptocurrencies out there; in fact, as of April 2021, there were over 9,500 cryptocurrencies in circulation listed on the Coinmarketcap. This number is expected to increase in the future as people’s interest in cryptocurrencies keeps rising. Although you might have heard about cryptocurrencies and known how it works, it’s possible you still don’t know what cryptocurrency actually is, or what means. The fields of cryptocurrency and the blockchain technology that drives cryptocurrencies can be a bit confusing. So, what is cryptocurrency? This article uses relatable terminology to explain in detail what cryptocurrency is, and the science of cryptography that decentralizes and drives cryptocurrencies, and makes them secure.
What is a Cryptocurrency?
What is the Blockchain?
Why the Blockchain now?
Lets Sum this Blockchain!
Why the “Blockchain” is next IT revolution you have not heard of..
Lets talk about Careers in the Blockchain!
Understand Crypto currencies, where to buy them, how to secure owned currencies and investment options. Presentation will give ideas to start investigating and exploration.
Discussed about the Blockchain and how it works
Also the advantages of Blockchain over centralized system and some drawbacks are also mentioned.
Discussion on bitcoin and Cryptocurrency
Creating our own cryptocurrency for startups.
Snapshots are attached.
Blockchain Ecosystem and Cryptocurrency RegulationsAmir Rafati
A blockchain is a general digital ledger of transactions that are executed on the network, e.g. using Bitcoin to buy a cup of coffee is a transaction.
All users of the network, ‘Nodes’, have a copy of the transaction records and can access them freely, a role previously played by centralized institutions. Therefore, the blockchain network is ‘decentralized’.
Basic information about what is Cryptocurrency ,what are there , benefits of cryptocurrency , how its works through blockchain technology, Crypto Mining ,where the currency can be stored, Uses of cryptocurrency and how to be hacker can hack it and caution about it.
Today, blockchain technology doesn't need to be implemented. A word that once was foreign has now earned accolades from individuals across the globe. This technology is being talked about by every business and investor. Blockchain started its journey as an underlying Bitcoin exchange technology, and it has gained so much popularity over the years. Everyone speaks about Blockchain, from students to working professionals; but what makes Blockchain so attractive is that you need to know the concepts of Blockchain technology for this.
An Introduction to Bitcoin, Blockchain and CryptocurrencyAmarpreet Singh
Heard that bitcoin value doubled again? or new cryptocurrency IPO’s are taking over the stock market! Well, cryptocurrency is just the tip of the iceberg. Blockchain technology is a lot more than just cryptocurrency and can revolutionize almost everything which surrounds us. This presentation will help you grab a quick introduction to Bitcoin, Blockchain and Cryptocurrency
Understanding Proof of Work (PoW) and Proof of Stake (PoS) AlgorithmsGautam Anand
We will focus on understanding "Proof of Stake (PoS)" Algorithm, how it different from "Proof of Work" algorithm, the performance benefits and security overview. We will also discuss the upcoming blockchain protocols that are planning to move to PoS.
Blockchain. Everyone talks about it, but how does it really work?
This talk covers the fundamentals and discusses real world examples of how blockchain is being used to transform healthcare, real estate, humanitarian aid, governance and other domains.
See the original talk at: https://www.facebook.com/thekasbahhub/videos/1875008969491362/
Blockchain overview, use cases, implementations and challengesSébastien Tandel
Most know about Bitcoin, the well-known crypto-currency. Less know the details about the underlying and enabling technology, Blockchain.
Hopefully, this presentation provides enough insights to understand blockchain concepts and why it's perceived to potentially disrupt many market segments, from retail to governments, from finance to health care. At last, I hope to brush fairly the many challenges of this rather new technology.
An introductory look at various Blockchain Technologies and examples. In this slide I explain about basics of Etherium and types of Blockchain technology currently present and some known public projects/examples which use Blockchain.
Blockchain technology is currently taking over the world with its amazing features. This presentation covers all you need to know about the basics of blockchain technology with beautiful animations
The project deals about how blockchain works, proof-of-work and merkle tree hash function. The project also tries to explain how the bitcoin uses ECDSA algorithmt power the cryptography.
Block chain and Bitcoin. A blockchain is a data structure that makes it possible to create a digital ledger of transactions and share it among a distributed network of computers.
There are many cryptocurrencies out there; in fact, as of April 2021, there were over 9,500 cryptocurrencies in circulation listed on the Coinmarketcap. This number is expected to increase in the future as people’s interest in cryptocurrencies keeps rising. Although you might have heard about cryptocurrencies and known how it works, it’s possible you still don’t know what cryptocurrency actually is, or what means. The fields of cryptocurrency and the blockchain technology that drives cryptocurrencies can be a bit confusing. So, what is cryptocurrency? This article uses relatable terminology to explain in detail what cryptocurrency is, and the science of cryptography that decentralizes and drives cryptocurrencies, and makes them secure.
What is a Cryptocurrency?
What is the Blockchain?
Why the Blockchain now?
Lets Sum this Blockchain!
Why the “Blockchain” is next IT revolution you have not heard of..
Lets talk about Careers in the Blockchain!
Understand Crypto currencies, where to buy them, how to secure owned currencies and investment options. Presentation will give ideas to start investigating and exploration.
Discussed about the Blockchain and how it works
Also the advantages of Blockchain over centralized system and some drawbacks are also mentioned.
Discussion on bitcoin and Cryptocurrency
Creating our own cryptocurrency for startups.
Snapshots are attached.
Blockchain Ecosystem and Cryptocurrency RegulationsAmir Rafati
A blockchain is a general digital ledger of transactions that are executed on the network, e.g. using Bitcoin to buy a cup of coffee is a transaction.
All users of the network, ‘Nodes’, have a copy of the transaction records and can access them freely, a role previously played by centralized institutions. Therefore, the blockchain network is ‘decentralized’.
Basic information about what is Cryptocurrency ,what are there , benefits of cryptocurrency , how its works through blockchain technology, Crypto Mining ,where the currency can be stored, Uses of cryptocurrency and how to be hacker can hack it and caution about it.
Today, blockchain technology doesn't need to be implemented. A word that once was foreign has now earned accolades from individuals across the globe. This technology is being talked about by every business and investor. Blockchain started its journey as an underlying Bitcoin exchange technology, and it has gained so much popularity over the years. Everyone speaks about Blockchain, from students to working professionals; but what makes Blockchain so attractive is that you need to know the concepts of Blockchain technology for this.
An Introduction to Bitcoin, Blockchain and CryptocurrencyAmarpreet Singh
Heard that bitcoin value doubled again? or new cryptocurrency IPO’s are taking over the stock market! Well, cryptocurrency is just the tip of the iceberg. Blockchain technology is a lot more than just cryptocurrency and can revolutionize almost everything which surrounds us. This presentation will help you grab a quick introduction to Bitcoin, Blockchain and Cryptocurrency
Understanding Proof of Work (PoW) and Proof of Stake (PoS) AlgorithmsGautam Anand
We will focus on understanding "Proof of Stake (PoS)" Algorithm, how it different from "Proof of Work" algorithm, the performance benefits and security overview. We will also discuss the upcoming blockchain protocols that are planning to move to PoS.
Blockchain. Everyone talks about it, but how does it really work?
This talk covers the fundamentals and discusses real world examples of how blockchain is being used to transform healthcare, real estate, humanitarian aid, governance and other domains.
See the original talk at: https://www.facebook.com/thekasbahhub/videos/1875008969491362/
Blockchain overview, use cases, implementations and challengesSébastien Tandel
Most know about Bitcoin, the well-known crypto-currency. Less know the details about the underlying and enabling technology, Blockchain.
Hopefully, this presentation provides enough insights to understand blockchain concepts and why it's perceived to potentially disrupt many market segments, from retail to governments, from finance to health care. At last, I hope to brush fairly the many challenges of this rather new technology.
An introductory look at various Blockchain Technologies and examples. In this slide I explain about basics of Etherium and types of Blockchain technology currently present and some known public projects/examples which use Blockchain.
Blockchain technology is currently taking over the world with its amazing features. This presentation covers all you need to know about the basics of blockchain technology with beautiful animations
The project deals about how blockchain works, proof-of-work and merkle tree hash function. The project also tries to explain how the bitcoin uses ECDSA algorithmt power the cryptography.
The speaker share his vision on the prospects of employing the technology for practical tasks. He presented basics of the blockchain architecture with case studies of JavaScript blockchain implementation using Node.js.
This presentation by Valerii Radchenko (Senior Software Engineer, Consultant, GlobalLogic, Kharkiv) was delivered at GlobalLogic Kharkiv JS TechTalk #2 on August 17, 2018.
Virtual or digital currencies, with Bitcoin chief amongst them, have been gaining momentum and investment over the last couple of years. Offering an almost costless means of making payments around the globe, virtual currencies have the potential to bring significant disruption to the banking industry. This potential is not lost on either Bitcoin startups or banks themselves. But how does Bitcoin actually work? A peer-to-peer network maintains the “blockchain”, an innovative cryptographic protocol which securely mediates payments between parties without mutual trust. This session will step through the structure of the blockchain, showing how it solves the “double spend” problem and allows decentralised processing of financial transactions. Whether Bitcoin will become the currency of the internet or it’s a bubble that is doomed to burst sooner or later, the blockchain itself will change the face of transactional banking and perhaps other industries along the way.
Presentation to the Sydney Financial Mathematics Workshop (11 March 2015)
http://www.qgroup.org.au/content/bitcoin-banking-and-blockchain
Blockchain has gained lots of attention in recent years. Bitcoin and Ethereum are leading the race. Crypto currencies in spite of uncertainty and volatility are here to stay. Smart contract programming is the future for the Internet 3.0.
In this case study, we are providing information about the Introduction of Blockchain Technology, Bitcoin and its environment setup, Ethereum coin, other cryptocurrencies, Bitcoin in education, and a case study of healthcare using blockchain.
A Complete Beginners Guide to Blockchain Technology Part 2 of 6. Slides from the #StartingBlock2015 tour by @blockstrap
Part 1: http://www.slideshare.net/Blockstrap/cbgtbt-part-1-workshop-introduction-primer
Part 2: http://www.slideshare.net/Blockstrap/02-blockchains-101
Part 3: http://www.slideshare.net/Blockstrap/03-transactions-101
Part 4: http://www.slideshare.net/Blockstrap/cbgtbt-part-4-mining
Part 5: http://www.slideshare.net/Blockstrap/05-blockchains-102
Part 6: http://www.slideshare.net/Blockstrap/06-transactions-102
A Primer on Blockchain and its Potential, with a Focus on the GCCZeyad T. Al Mudhaf
During my summer internship at BECO Capital, a technology-focused Venture Capital firm based in Dubai, I put together this primer on blockchain that demystifies this hyped up technology, covers key investment trends in the space both globally and regionally within the GCC*, and highlights both the barriers and enablers for wider blockchain adoption in the region. *The GCC is the Gulf Cooperation Council - comprised of the United Arab Emirates, Saudi Arabia, Kuwait, Bahrain, Qatar, and Oman.
A blockchain is a decentralized, distributed and incorruptible digital ledger that is used to record transactions across many computers. This presentation covers distributed ledger technology (DLT) or blockchain technology terms, fundamentals, and architecture. Includes discussion of hash functions, merkle tree, digital signature, proof of work, nonce, cryptography, double spend and transactions.
Assembly Dili İle Binary Search GerçekleştirimiSeval Çapraz
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Importance of software quality assurance to prevent and reduce software failu...Seval Çapraz
Importance of software quality assurance to prevent and reduce software failures:
Document Management System In Defence Industry Case Study by Seval Çapraz
What is Datamining? Which algorithms can be used for Datamining?Seval Çapraz
This presentation includes what is datamining, which technics and algorithms are available in datamining. This presentation helps you to understand the concepts of datamining.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
Let's dive deeper into the world of ODC! Ricardo Alves (OutSystems) will join us to tell all about the new Data Fabric. After that, Sezen de Bruijn (OutSystems) will get into the details on how to best design a sturdy architecture within ODC.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
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Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
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Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
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Assuring Contact Center Experiences for Your Customers With ThousandEyes
A Quick Start To Blockchain by Seval Capraz
1. 1
A Quick Start To Blockchain
Seval ÇAPRAZ
ASELSAN Inc.
November 2021 TURKEY
2. WHAT IS BLOCKCHAIN?
• Blockchain is one of the most innovative discoveries of
the past century.
• The first cryptocurrency, Bitcoin, was proposed in 2008
by Satoshi Nakamoto with a white paper.
• Initially, the first Bitcoin was used in 2009. After ten
years, this electronic coin is used by millions of people
every day. Nowadays, there are dozens of
cryptocurrencies such as Bitcoin, Ethereum, Tether,
Binance Coin, XRP etc.
• Initially, blockchain was designed specifically for
cryptocurrencies but it can be utilized for endless other
use cases thanks to its beneficial features.
2
3. • The infrastructure of blockchain is based on a peer-to-peer (p2p) network.
• All nodes on the network have a copy of the chain. Once anyone sends a Bitcoin to another, it
becomes permanent and verifiable. It is an excellent chain with linked blocks. It is nearly
impossible to counterfeit or double-spend.
3
Peer-to-Peer (p2p)
4. Distributed Ledger Technology
• The blocks are linked and become a chain. Then the chain is stored by all users in the network.
This design is called distributed ledger technology.
• Ledger is a record of any transaction or data. If a ledger is distributed, there is no need for a
central authority or middleman. Also distributed systems reduce the costs of transactions. In
addition to this, it is more secure and robust than central systems.
• Blockchain is one type of distributed ledger technology. It has more features.
4
8. How we hold data?
• Blockchain is a new kind of database. We can hold the data in blocks or outside of the block. If we
store the data outside of the blockchain, we can hide only the address in the blockchain. This is
called off-blockchain.
8
DB Address Address Address
Off-Blockchain
9. Hashing Algorithms
9
• To link the blocks, simple cryptography is used: hashing
algorithms such as SHA-256, Keccak-256 etc.
• The hashing means taking an input string of any length
and giving out an output of a fixed length.
• SHA-256 always produces an output with 256 bits
length hash value.
• Some hash algorithms are not collision resistant such as
MD-5 or SHA-1.
• On the other hand, SHA-256 and Keccak-256 have
strong collision resistance.
• SHA-256 is currently being used by Bitcoin.
• Keccak-256 is currently being used by Ethereum.
SHA-256
“The quick brown fox did some crypto”
410312395834291203…
SHA-256
“The quick brown Fox did some crypto”
983249120432492340…
10. Block Mining
10
• The blocks can be created after a procedure called mining. Mining is used for transactions’
validity. If a transaction is valid, the mining operation creates a block with this transaction record.
• After a block is created, the miner announces it to the network. The peers on the network verifies
this block, and it joins the chain permanently. Mining protects the chain from the double-
spending problem.
• Bitcoin uses a very difficult mathematical problem to mine a block because everyone wants to
mine blocks and get rewards. Solving this difficult mathematical problem is called proof-of-work.
• Miners try different nonce values more than billions of times. It takes approximately 10 minutes
to successfully mine a block.
• Mining requires a lot of computational power.
11. Hash-based Proof of Work
11
• Can’t compute an input from an output.
• To find a hash with N zeros at the start of the input, requires 2N computations…proves
computational work.
• If we hash an incrementing “nonce” as the hash input, we can go looking for zeros:
in 3e-05 seconds, nonce = 0 yielded 0 zeros. value = 4c8f1205f49e70248939df9c7b704ace62c2245aba9e81641edf…
in 0.000138 seconds, nonce = 12 yielded 1 zeros. value = 05017256be77ad2985b36e75e486af325a620a9f29c54…
in 0.000482 seconds, nonce = 112 yielded 2 zeros. value = 00ae7e0956382f55567d0ed9311cfd41dd2cf5f0a7137…
in 0.014505 seconds, nonce = 3728 yielded 3 zeros. value = 000b5a6cfc0f076cd81ed3a60682063887cf055e47b…
in 0.595024 seconds, nonce = 181747 yielded 4 zeros. value = 0000af058b74703b55e27437b89b1ebcc46f45ce55d6….
in 3.491151 seconds, nonce = 1037701 yielded 5 zeros. value = 00000e55bd0d2027f3024c378e0cc511548c94fbeed0e….
in 32.006105 seconds, nonce = 9913520 yielded 6 zeros. value = 00000077a77854ee39dc0dc996dea72dad8852afbde6….
in 590.89462 seconds, nonce = 186867248 yielded 7 zeros. value = 0000000225060b16117b23dbea9ce6be86ac439d….
in 4686.171007 seconds, nonce = 1424462909 yielded 8 zeros. value = 000000002dd743724609a9f57260e2492908d….
12. PGP (Pretty Good Privacy)
Private Key: A secret key that you don’t share
Public Key: Key that you share with others
12
14. Transactions
14
“If you don’t own your
private key, you don’t
own your bitcoins.”
• This is how the Bitcoin private key looks:
E9873D79C6D87DC0FB6A5778633389F4453213303DA61F20BD67FC233AA33262
15. Consensus Mechanism
15
• Bitcoin and Ethereum use classical proof of work mechanisms as we mentioned above. Other than
proof of work (PoW), there are a few popular methods for consensus mechanisms: proof of
authority, proof of personhood, proof of space, proof of stake etc. Which one is better than the
other?
16. Consensus Mechanism
16
• If someone has more than half of the computational resources of all peers on the network, he
starts to control the blockchain. This is known as 51% attack.
• Mining has to be competitive to provide a reliable and sustainable chain. To sum up, creating a
block should be difficult, however verifying it should be very easy. To verify a new block, there
should be a consensus like the majority of the network should verify and agree that the block is
valid.
• Byzantine Fault Tolerant (BFT) is one of the features of consensus mechanisms. It reaches
consensus as long as the majority (like two-thirds of the network) agree without any central
authority. The solution could fail only if the malicious party captures 50% of the network power.
17. Smart Contracts
17
• Blockchain is a new kind of database. In classical relational databases, we can create stored
procedures to run whenever we want. This feature exists in blockchain via smart contracts.
• Smart contracts can be used for creating a protocol or program on blockchain. Once it is deployed,
it is automatically executed by the blockchain and it cannot be changed.
• It is an agreement between users. Ethereum is the most popular blockchain to run smart
contracts by the help of Solidity programming language.
• In order to create smart contracts, Bitcoin provides a Turing-incomplete script language.
• In current proposed designs, smart contracts are used for access control for the data on the
blockchain.
18. Cryptography
18
• Blockchain has a cryptography to provide authentication and verification for network users on p2p
system.
• Kerckhoffs’s principle states that
• “a cryptosystem should be secure even if everything about
the system, except the key, is public knowledge.”
• The blockchain’s asymmetric cryptosystem relies on public and private keys. The main issue in this
cryptosystem is recovering lost private keys. It is nearly impossible.
• Wallet systems store the user’s private keys. This may cause the private keys to be lost or stolen.
• For instance, every Bitcoin address is based on a secret key, from which the public key (associated
to a Bitcoin address) is calculated.
• Once you have the bitcoin private key for an address, you have the control of that address and can
use it to transfer funds.