Thursday, October 21, 2021

Wednesday, October 20, 2021

What is NFT?

 

What is NFT?

NFT, or Non-Fungible Token, is a concept that is related to fungible tokens. If we compare it to the real world, fungible tokens are like currency: if you have $500 USD, you can divide it up, spend it in parts, get spare change, and continue to make more purchases with the change you receive. On the other hand, non-fungible tokens are unique and indivisible. Some examples could be: artworks, treasures in videogames, property deeds, or even certificates to prove wine provenance. When you trade a non-fungible token, you no longer own it, and since it is indivisible, there is no concept of spare change.

NFTs are issued on distributed ledgers on the blockchain. As such, as long as the ledger and the chain still exist, the record stating your NFT ownership will be intact. It will not be tampered with, removed, or disappear. When an NFT is issued, the contract will contain identifying information of the token including: the ID of the token, and a way to link to the assets it represents. These are the 2 main reasons why NFTs are optimal to prove a person’s ownership of an asset:

  1. The information is unalterable once it is on the blockchain
  2. NFT tokens are intrinsically unique, immutable, and indivisible

Similarly, NFT’s unique properties allow for it to be used in videogames to represent treasures or characters in the game. The most prominent example would be that of CryptoKitties. CryptoKitties is a blockchain game on Ethereum that allows players to buy, breed, collect and sell virtual cats. In the art world, NFTs can be applied to paintings, music copyrights, and various collectibles. A notable example would be encryption artist Beeple’s sale of their work: EVERYDAYS: THE FIRST 5000 DAYS, that was auctioned off for $69.34 million USD. NFTs are also commonly used in other industries in the form of digital certificates, identity authentication, and domain names.

So, how did the concept of NFTs come about? It started towards the end of 2017 when Dieter Shirley, CTO of CryptoKitties, released EIP-721 (Ethereum Implementation Proposal 721.) EIP-721 was different from ERC20 standard, which was very popular at the time and had highly sought-after ICO tokens. EIP-721 proposed, for the first time, tokens that were not interchangeable. Soon after, the concept of NFTs started to gain traction in different applications, including CryptoKitties. Nowadays, it is increasingly common to see NFT auctions hitting record numbers in the news.

Sunday, November 8, 2020

How to Calculate Return on Investment (ROI)

 

How to Calculate Return on Investment (ROI)

ROI is a way to measure an investment's performance. As you'd expect, it's also a great way to compare the profitability of different investments. Naturally, an investment with a higher ROI is better than an investment with a lower (or negative) ROI. Curious how to measure this for your own portfolio? Let's read on.

 

Introduction

Whether you're day trading, swing trading, or a long-term investor, you should always measure your performance. Otherwise, how would you know if you're doing well? One of the great benefits of trading is that you can rigorously measure how you're doing with objective metrics. This can greatly help eliminate emotional and cognitive biases. 

So, how is this useful? Well, the human mind tends to build narratives around everything as it tries to make sense of the world. However, you can't "hide" from numbers. If you're producing negative returns, something should be changed in your strategy. Similarly, if you feel like you're doing well but the numbers aren't reflecting that, you're probably a victim of your biases.

We've discussed risk managementposition sizing, and setting a stop-loss. But how do you measure the performance of your investments? And how can you compare the performance of multiple investments? This is where the ROI calculation comes in handy. In this article, we'll discuss how to calculate return on investment (ROI).

 

What is return on investment (ROI)?

Return on investment (ROI) is a way to measure an investment's performance. It also can be used to compare different investments.

There are multiple ways to calculate returns, and we'll cover some of them in the next chapter. For now, though, it's enough to understand that ROI measures the gains or losses compared to the initial investment. In other words, it's an approximation of an investment's profitability. Compared to the original investment, a positive ROI means profits, and a negative ROI means losses.

ROI calculation applies to not just trading or investment, but any kind of business or purchase. If you plan to open or buy a restaurant, you should do some number crunching first. Would opening it make sense from a financial perspective? Calculating an estimated ROI based on all your projected expenses and returns may help you make a better business decision. If it seems like the business would turn a profit in the end (i.e., have a positive ROI), it may be worth getting it started.

Also, ROI can help evaluate the results of transactions that already happened. For example, let's say you buy an old exotic car for $200,000. You then use it for two years and spend $50,000 on it. Now suppose that the car's price goes up on the market and you can now sell it for $300,000. Not only did you enjoy this car for two years, but it also brought you a sizable return on your investment. How much would that be exactly? Let's find out.

 

How to calculate return on investment (ROI)

The ROI formula is quite simple. You take the current value of the investment and subtract the original investment cost. Then, you divide this sum by the original cost of the investment.

ROI = (current value - original cost) / original cost

So, how much profit would you make by selling the exotic car?

ROI = (300,000 - 200,000) / 200,000 = 0.5

Your ROI is 0.5. If you multiply it by 100, you get the rate of return (ROR).

0.5 x 100 = 50

This means that you made a 50% gain on your original investment. However, you need to take into account how much was spent on the car to get the full picture. So, let's subtract that from the current value of the car:

300,000 - 50,000 = 250,000

Now, you can calculate ROI while taking into account the expenses:

ROI = (250,000 - 200,000) / 200,000 = 0.25

Your ROI is 0.25 (or 25%). This means that if we multiply your cost of investment ($200,000) by your ROI (0.25), we can find the net profit, which is $50,000.

200,000 x 0.25 = 50,000

 

The limitations of ROI

So, ROI is very easy to understand and brings a universal measure of profitability. Are there any limitations? Sure.

One of the biggest limitations of ROI is that it doesn't take into account the time period. Why does this matter? Well, time is a crucial factor for investments. There could be other considerations (like liquidity and security), but if an investment brings 0.5 ROI in a year, that's better than 0.5 ROI in five years. This is why you may see some talking about annualized ROI, which represents the investment returns (gains) you could expect over the course of a year.

Still, ROI won't take into account other aspects of an investment. A higher ROI doesn't necessarily mean a better investment. What if you can't find anyone willing to buy your investment and get stuck with it for a long period of time? What if the underlying investment has poor liquidity?

Another factor to consider is risk. An investment might have a very high prospective ROI, but at what cost? If there's a high chance that it goes to zero, or that your funds become inaccessible, then the prospective ROI isn't all that important. Why? The risk of holding this asset for a long time is very high. Sure, the potential reward could also be high, but losing the entire original investment is certainly not what you want.

Just purely looking at ROI won't give you insights into its safety, so you should consider other metrics as well. You could start by calculating the risk/reward ratio for each trade and investment. This way, you can get a better picture of the quality of each bet. In addition, some stock market analysts may also consider other factors when evaluating potential investments. These can include cash flows, interest rates, capital gains tax, return on equity (ROE), and more.

Thursday, September 24, 2020

The Complete Beginner's Guide to Decentralized Finance (DeFi)

What is Decentralized Finance (DeFi)?

Decentralized Finance (or simply DeFi) refers to an ecosystem of financial applications that are built on top of blockchain networks. 

More specifically, the term Decentralized Finance may refer to a movement that aims to create an open-source, permissionless, and transparent financial service ecosystem that is available to everyone and operates without any central authority. The users would maintain full control over their assets and interact with this ecosystem through peer-to-peer (P2P)decentralized applications (dapps).

The core benefit of DeFi is easy access to financial services, especially for those who are isolated from the current financial system. Another potential advantage of DeFi is the modular framework it is built upon - interoperable DeFi applications on public blockchains will potentially create entirely new financial markets, products, and services. 

This article will provide an introductory dive into DeFi, its potential applications, promises, limitations, and more.

 

What are the main advantages of DeFi?

Traditional finance relies on institutions such as banks to act as intermediaries, and courts to provide arbitration. 

DeFi applications do not need any intermediaries or arbitrators. The code specifies the resolution of every possible dispute, and the users maintain control over their funds at all times. This reduces the costs associated with providing and using these products and allows for a more frictionless financial system.

As these new financial services are deployed on top of blockchains, single points of failure are eliminated. The data is recorded on the blockchain and spread across thousands of nodes, making censorship or the potential shutdown of a service a complicated undertaking. 

Since the frameworks for DeFi applications can be built in advance, deploying one becomes much less complicated and much more secure.

Another significant advantage of such an open ecosystem is the ease of access for individuals who otherwise wouldn’t have access to any financial services. Since the traditional financial system relies on the intermediaries making a profit, their services are typically absent from locations with low-income communities. However, with DeFi, the costs are significantly reduced, and low-income individuals can also benefit from a broader range of financial services.

 

What are the potential use cases for DeFi?

Borrowing & Lending

Open lending protocols are one of the most popular types of applications that are part of the DeFi ecosystem. Open, decentralized borrowing and lending have many advantages over the traditional credit system. These include instant transaction settlement, the ability to collateralize digital assets, no credit checks, and potential standardization in the future. 

Since these lending services are built on public blockchains, they minimize the amount of trust required and have the assurance of cryptographic verification methods. Lending marketplaces on the blockchain reduce counterparty risk, make borrowing and lending cheaper, faster, and available to more people.

 

Monetary banking services

As DeFi applications are, by definition, financial applications, monetary banking services are an obvious use case for them. These can include the issuance of stablecoins, mortgages, and insurance.

As the blockchain industry is maturing, there is an increased focus on the creation of stablecoins. They are a type of cryptoasset that is usually pegged to a real-world asset but can be transferred digitally with relative ease. As cryptocurrency prices can fluctuate rapidly at times, decentralized stablecoins could be adopted for everyday use as digital cash that is not issued and monitored by a central authority. 

Largely because of the number of intermediaries needing to be involved, the process of getting a mortgage is expensive and time-consuming. With the use of smart contracts, underwriting and legal fees may be reduced significantly.

Insurance on the blockchain could eliminate the need for intermediaries and allow the distribution of risk between many participants. This could result in lower premiums with the same quality of service. 

If you’d like to read more on the subject of blockchain and banking, we recommend reading our article How Blockchain Technology Will Impact the Banking Industry.

 

Decentralized Marketplaces

This category of applications can be challenging to assess, as it is the segment of DeFi that gives the most room for financial innovation. 

Arguably, some of the most crucial DeFi applications are decentralized exchanges (DEXes). These platforms allow users to trade digital assets without the need for a trusted intermediary (the exchange) to hold their funds. The trades are made directly between user wallets with the help of smart contracts. 

Since they require much less maintenance work, decentralized exchanges typically have lower trading fees than centralized exchanges. 

Blockchain technology may also be used to issue and allow ownership of a wide range of conventional financial instruments. These applications would work in a decentralized way that cuts out custodians and eliminates single points of failure.

Security token issuance platforms, for example, may provide the tools and resources for issuers to launch tokenized securities on the blockchain with customizable parameters.  

Other projects may allow the creation of derivatives, synthetic assets, decentralized prediction markets, and many more.

 

What role do smart contracts have in DeFi?

Most of the existing and potential applications of Decentralized Finance involve the creation and execution of smart contracts. While a usual contract uses legal terminology to specify the terms of the relationship between the entities entering the contract, a smart contract uses computer code.

Since their terms are written in computer code, smart contracts have the unique ability also to enforce those terms through computer code. This enables the reliable execution and automation of a large number of business processes that currently require manual supervision.

Using smart contracts is faster, easier, and reduces risk for both parties. On the other hand, smart contracts also introduce new types of risks. As computer code is prone to have bugs and vulnerabilities, the value and confidential information locked in smart contracts are at risk.

 

What challenges does DeFi face?

·       Poor performance: Blockchains are inherently slower than their centralized counterparts, and this translates to the applications built on top of them. The developers of DeFi applications need to take these limitations into account and optimize their products accordingly.

·       High risk of user error: DeFi applications transfer the responsibility from the intermediaries to the user. This can be a negative aspect for many. Designing products that minimize the risk of user error is a particularly difficult challenge when the products are deployed on top of immutable blockchains.

·       Bad user experience: Currently, using DeFi applications requires extra effort on the user’s part. For DeFi applications to be a core element of the global financial system, they must provide a tangible benefit that incentivizes users to switch over from the traditional system.

·       Cluttered ecosystem: It can be a daunting task to find the application that is the most suitable for a specific use case, and users must have the ability to find the best choices. The challenge is not only building the applications but also thinking about how they fit into the broader DeFi ecosystem.

 

What is the difference between DeFi and open banking?

Open banking refers to a banking system where third-party financial service providers are given secure access to financial data through APIs. This enables the networking of accounts and data between banks and non-bank financial institutions. Essentially, it allows new types of products and services within the traditional financial system. 

DeFi, however, proposes an entirely new financial system that is independent of the current infrastructure. DeFi is sometimes also referred to as open finance.

For example, open banking could allow the management of all traditional financial instruments in one application by drawing data from several banks and institutions securely. 

Decentralized Finance, on the other hand, could allow the management of entirely new financial instruments and new ways of interacting with them.

  

Tuesday, July 28, 2020

Proof of Stake Explained

What is Proof of Stake?

The Proof of Stake consensus algorithm was introduced back in 2011 on the Bitcointalk forum to solve the problems of the current most popular algorithm in use - Proof of Work. While they both share the same goal of reaching consensus in the blockchain, the process to reach the goal is quite different.

How does it work?

The Proof Of Stake algorithm uses a pseudo-random election process to select a node to be the validator of the next block, based on a combination of factors that could include the staking age, randomization, and the node’s wealth.
It’s good to note that in Proof of Stake systems, blocks are said to be ‘forged’ rather than mined. Cryptocurrencies using Proof of Stake often start by selling pre-mined coins or they launch with the Proof of Work algorithm and later switch over to Proof of Stake.
Where in Proof of Work-based systems more and more cryptocurrency is created as rewards for miners, the Proof-of-Stake system usually uses transaction fees as a reward.
Users who want to participate in the forging process, are required to lock a certain amount of coins into the network as their stake. The size of the stake determines the chances for a node to be selected as the next validator to forge the next block - the bigger the stake, the bigger the chances. In order for the process not to favor only the wealthiest nodes in the network, more unique methods are added into the selection process. The two most commonly used methods are ‘Randomized Block Selection’ and ‘Coin Age Selection’.
In the Randomized Block Selection method the validators are selected by looking for nodes with a combination of the lowest hash value and the highest stake and since the size of stakes are public, the next forger can usually be predicted by other nodes.
The Coin Age Selection method chooses nodes based on how long their tokens have been staked for. Coin age is calculated by multiplying the number of days the coins have been held as stake by the number of coins that are staked. Once a node has forged a block, their coin age is reset to zero and they must wait a certain period of time to be able to forge another block - this prevents large stake nodes from dominating the blockchain.
Each cryptocurrency using Proof of Stake algorithm has their own set of rules and methods combined for what they think is the best possible combination for them and their users.
When a node gets chosen to forge the next block, it will check if the transactions in the block are valid, signs the block and adds it to the blockchain. As a reward, the node receives the transaction fees that are associated with the transactions in the block.
If a node wants to stop being a forger, its stake along with the earned rewards will be released after a certain period of time, giving the network time to verify that there are no fraudulent blocks added to the blockchain by the node.

Security

The stake works as a financial motivator for the forger node not to validate or create fraudulent transactions. If the network detects a fraudulent transaction, the forger node will lose a part of its stake and its right to participate as a forger in the future. So as long as the stake is higher than the reward, the validator would lose more coins than it would gain in case of attempting fraud.
In order to effectively control the network and approve fraudulent transactions, a node would have to own a majority stake in the network, also known as the 51% attack. Depending on the value of a cryptocurrency, this would be very impractical as in order to gain control of the network you would need to acquire 51% of the circulating supply.
The main advantages of the Proof of Stake algorithm are energy efficiency and security.
A greater number of users are encouraged to run nodes since it’s easy and affordable. This along with the randomization process also makes the network more decentralized, since mining pools are no longer needed to mine the blocks. And since there is less of a need to release many new coins for a reward, this helps the price of a particular coin stay more stable.
It’s good to remember that the cryptocurrency industry is rapidly changing and evolving and there are also several other algorithms and methods being developed and experimented with.

Wednesday, July 22, 2020

What Is Ripple?

Formerly known as OpenCoin, Ripple is a privately held company that is building a payment and exchange network (RippleNet) on top of a distributed ledger database (XRP Ledger). The main goal of Ripple is to connect banks, payment providers and digital asset exchanges, enabling faster and cost-efficient global payments. 

History
Ripple was first idealized in 2004 by Ryan Fugger, who developed the first prototype of Ripple as a decentralized digital monetary system (RipplePay). The system went live in 2005 and was meant to provide secure payment solutions within a global network.
In 2012, Fugger handed over the project to Jed McCaleb and Chris Larsen and together they founded the US-based technology company OpenCoin. From that point on, Ripple started to be built as a protocol focused on payment solutions for banks and other financial institutions. In 2013, OpenCoin was rebranded to Ripple Labs, which was later rebranded to Ripple, in 2015.

The XRP Ledger (XRPL)
Based on the work of Fugger and inspired by the creation of Bitcoin, Ripple deployed the Ripple Consensus Ledger (RCL) in 2012 - along with its native cryptocurrency XRP. The RCL was later renamed to XRP Ledger (XRPL).
The XRPL works as a distributed economic system that not only stores all the accounting information of the network participants but also provides exchange services across multiple currency pairs. Ripple presents the XRPL as an open-source distributed ledger that allows for real-time financial transactions. These transactions are secured and verified by the participants of the network through a consensus mechanism. 
Unlike Bitcoin, however, the XRP Ledger is not based on a Proof of Work consensus algorithm and, therefore, does not rely on a process of mining to verify transactions. Instead, the network reaches consensus through the use of its own customized consensus algorithm – formerly known as the Ripple Protocol Consensus Algorithm (RPCA).
The XRPL is managed by a network of independent validating nodes that constantly compare their transaction records. Anyone is able to not only set up and run a Ripple validator node but also to choose which nodes to trust as validators. However, Ripple recommends its clients to use a list of identified, trusted participants to validate their transactions. This list is known as the Unique Node List (UNL).
The UNL nodes exchange transaction data between each other until all of them agree on the current state of the ledger. In other words, transactions that are agreed upon by a supermajority of UNL nodes are considered valid and the consensus is achieved when all these nodes apply the same set of transactions to the ledger.
According to Ripple’s official website, Ripple is a privately held company that founded the development of the XRPL as an open-source distributed ledger. This means that anyone can contribute to the code and that the XRPL is able to continue even if the company ceases to exist.

RippleNet
In contrast to XRPL, the RippleNet is exclusive to the Ripple company and was built on top of the XRPL as a payment and exchange network.
The RippleNet currently offers a 3-product suite that is designed as a payment solution system for banks and other financial institutions. Currently, RippleNet has three major products: xRapid, xCurrent, and xVia.

xRapid
In short, xRapid is an on-demand liquidity solution that uses XRP as a global bridge currency between multiple fiat currencies. Both XRP and xRapid rely on the XRP Ledger, which enables faster confirmation times and much lower fees when compared to conventional methods.
Let’s take a simple example. Bob from Australia wants to send $100 to Alice who is based in India. Bob transfers the money via a financial institution called FIN. In order to perform the transaction, FIN uses the xRapid solution to create a connection with asset exchanges in both the originating and destination country. This way, the company is able to convert Bob’s $100 to XRP, which provides the necessary liquidity for the final payment. In a matter of seconds, the XRP is converted to Indian Rupees and Alice is able to withdraw the money from the asset exchange located in India.

xCurrent
xCurrent is a solution designed to provide instant settlement and tracking of cross-border payments between RippleNet members. Unlike xRapid, the xCurrent solution is not based on the XRP Ledger and does not use the XRP cryptocurrency by default. The xCurrent is built around the Interledger Protocol (ILP), which was designed by Ripple as a protocol for connecting different ledgers or payment networks. 

The four basic components of xCurrent are:

1.     Messenger - The xCurrent messenger provides peer-to-peer communication between connected RippleNet financial institutions. It is used to exchange information regarding risk and compliance, fees, FX rates, payment details and expected time of funds delivery.
2.     Validator - Validator is used to cryptographically confirm the success or failure of a transaction and also to coordinate moving of funds across the Interledger. Financial institutions can run their own validator or can rely on a third-party validator.
3.     ILP Ledger - The Interledger Protocol is implemented into existing banking ledgers, which creates the ILP Ledger. The ILP Ledger functions as a sub-ledger and is used to track credits, debits, and liquidity across transacting parties. Funds are settled atomically, meaning that they are either settled instantly or not at all.
4.     FX Ticker - FX ticker is used to define exchange rates between transacting parties. It tracks the current state of each configured ILP Ledger.
Although xCurrent is primarily designed for fiat currencies, it also supports cryptocurrency transactions.

xVia
xVia is an API-based standardized interface that allows banks and other financial service providers to interact within a single framework - without having to rely on multiple payment network integrations. xVia allow banks to create payments through other banking partners that are connected to RippleNet and also enables them to attach invoices or other information to their transactions.

Closing thoughts
While Bitcoin is known as the first cryptocurrency and Ethereum is recognized for the creation of a platform for smart contracts, we may consider Ripple network as a currency exchange system that focuses on global payment solutions for banks and other financial institutions.
RippleNet may be implemented on top of the existing banking infrastructure as a way to complement and improve the traditional payment system. xCurrent allows for cost-efficient real-time payments across financial institutions, xRapid uses XRP as a bridge borderless currency to provide on-demand liquidity pools, and xVia facilitates the integration and communication of all RippleNet participants.


Monday, July 20, 2020

What Makes a Blockchain Secure?

Blockchains are secured through a variety of mechanisms that include advanced cryptographic techniques and mathematical models of behavior and decision-making. Blockchain technology is the underlying structure of most cryptocurrency systems and is what prevents this kind of digital money from being duplicated or destroyed.
The use of blockchain technology is also being explored in other contexts where data immutability and security are highly valuable. A few examples include the act of recording and tracking charity donations, medical databases, and supply chain management.
However, blockchain security is far from being a simple subject. Therefore, it is important to understand the basic concepts and mechanisms that grant robust protection to these innovative systems.

The concepts of immutability and consensus
Although many features play into the security associated with blockchain, two of the most important are the concepts of consensus and immutability. Consensus refers to the ability of the nodes within a distributed blockchain network to agree on the true state of the network and on the validity of transactions. Typically, the process of achieving consensus is dependent on the so-called consensus algorithms.
Immutability, on the other hand, refers to the ability of blockchains to prevent alteration of transactions that have already been confirmed. Although these transactions are often relating to the transfer of cryptocurrencies, they may also refer to the record of other non-monetary forms of digital data.
Combined, consensus and immutability provide the framework for data security in blockchain networks. While consensus algorithms ensure that the rules of the system are being followed and that all parties involved agree on the current state of the network - immutability guarantees the integrity of data and transaction records after each new block of data is confirmed to be valid.

The role of cryptography in blockchain security
Blockchains rely heavily on cryptography to achieve their data security. In this context, the so-called cryptographic hashing functions are of fundamental importance. Hashing is a process whereby an algorithm (hash function) receives an input of data of any size and returns an output (hash) that contains a predictable and fixed size (or length).
Regardless of the input size, the output will always present the same length. But if the input changes, the output will be completely different. However, if the input doesn’t change, the resulting hash will always be the same - no matter how many times you run the hash function.
Within blockchains, these output values, known as hashes, are used as unique identifiers for data blocks. The hash of each block is generated in relation to the hash of the previous block, and that is what creates a chain of linked blocks. The block hash is dependent on the data contained within that block, meaning that any change made to the data would require a change to the block hash.
Therefore, the hash of each block is generated based on both the data contained within that block and the hash of the previous block. These hash identifiers play a major role in ensuring blockchain security and immutability.
Hashing is also leveraged in the consensus algorithms used to validate transactions. On the Bitcoin blockchain, for example, the Proof of Work (PoW) algorithm utilizes a hash function called SHA-256. As the name implies, SHA-256 takes data input and returns a hash that is 256 bits or 64 characters long.
In addition to providing protection for transaction records on ledgers, cryptography also plays a role in ensuring the security of the wallets used to store units of cryptocurrency. The paired public and private keys that respectively allow users to receive and send payments are created through the use of asymmetric or public-key cryptography. Private keys are used to generate digital signatures for transactions, making it possible to authenticate ownership of the coins that are being sent.
Though the specifics are beyond the scope of this article, the nature of asymmetric cryptography prevents anyone but the private key holder from accessing funds stored in a cryptocurrency wallet, thus keeping those funds safe until the owner decides to spend them (as long as the private key is not shared or compromised).

Cryptoeconomics
In addition to cryptography, a relatively new concept known as cryptoeconomics also plays a role in maintaining the security of blockchain networks. It is related to a field of study known as game theory, which mathematically models decision-making by rational actors in situations with predefined rules and rewards. While traditional game theory can be broadly applied to a range of cases, cryptoeconomics specifically models and describes the behavior of nodes on distributed blockchain systems.
In short, cryptoeconomics is the study of the economics within blockchain protocols and the possible outcomes that their design may present based on its participants’ behavior. Security through cryptoeconomics is based on the notion that blockchain systems provide greater incentives for nodes to act honestly than to adopt malicious or faulty behaviors. Once again, the Proof of Work consensus algorithm used in Bitcoin mining offers a good example of this incentive structure.
When Satoshi Nakamoto created the framework for Bitcoin mining, it was intentionally designed to be a costly and resource-intensive process. Owing to its complexity and computational demands, PoW mining involves a considerable investment of money and time - regardless of where and who the mining node is. Therefore, such a structure provides a strong disincentive for malicious activity and significant incentives for honest mining activity. Dishonest or inefficient nodes will be quickly expelled from the blockchain network, while the honest and efficient miners have the potential of getting substantial block rewards.
Similarly, this balance of risks and rewards also grants protection against potential attacks that could undermine consensus by placing the majority hash rate of a blockchain network into the hands of a single group or entity. Such attacks, known as 51 percent attacks, could be extremely damaging if successfully executed. Due to the competitiveness of Proof of Work mining and the magnitude of the Bitcoin network, the likelihood of a malicious actor gaining control of a majority of nodes is extremely minimal.
Furthermore, the cost in computing power needed to attain 51 percent control of a huge blockchain network would be astronomical, providing an immediate disincentive to make such a large investment for a relatively small potential reward. This fact contributes to a characteristic of blockchains known as Byzantine Fault Tolerance (BFT), which is essentially the ability of a distributed system to continue to work normally even if some nodes become compromised or act maliciously. 
As long as the cost of establishing a majority of malicious nodes remains prohibitive and better incentives exist for honest activity, the system will be able to thrive without significant disruption. It is worth noting, however, that small blockchain networks are certainly susceptible to majority attack because the total hash rate devoted to those systems is considerably lower than the one of Bitcoin.

Closing thoughts
Through the combined use of game theory and cryptography, blockchains are able to attain high levels of security as distributed systems. As with nearly all systems, however, it is critical that these two fields of knowledge are properly applied. A careful balance between decentralization and security is vital to building a reliable and effective cryptocurrency network.
As the uses of blockchain continue to evolve, their security systems will also change in order to meet the needs of different applications. The private blockchains now being developed for business enterprises, for example, rely much more on security through access control than on the game theory mechanisms (or cryptoeconomics) that are indispensable to the safety of most public blockchains.