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What is the Bitcoin encryption algorithm? Sha256 decryption and mining features Comparative characteristics of algorithms in relation to mining

Alexander Markov

The abbreviation SHA 256 stands for Secure Hashing Algorithm - a popular hashing mechanism created by specialists from the NSA. The key task of the algorithm is to convert random information into values with a fixed length; in the future it will be used to identify this information.

History of appearance

Let us immediately note that this is a second generation algorithm, created on the basis of its predecessor - SHA-1, which in turn was developed back in 1995 exclusively for use for civilian purposes. An updated version of the now popular algorithm was created by employees of the National Security Agency in 2002.

Three years later, a patent appeared allowing the algorithm to be used for civilian purposes. The third version of the popular mechanism appeared in 2012, its development was carried out by specialists from the National Standards Agency. Over time, SHA-3 completely replaced its predecessors.

It is not possible to decrypt the converted data because the hash sum is not considered an encryption process in the classical interpretation of this process. The one-way encryption algorithm processes an unlimited amount of information.

It is worth noting that absolutely all existing versions of the Secure Hashing Algorithm were created according to the Merkle-Damgaard principle: information is divided into uniform categories. Each group undergoes one-way compression, resulting in significantly reduced data length.

This encryption method has many advantages:

data compression is carried out quickly;
it is impossible to roll back the conversion process without keys;
the likelihood of collisions is reduced to zero.

Technical specifications

The protocol is designed for data that is divided into parts, each 64 bytes in size. The algorithm provides consolidation, as a result of which a 256-bit code appears. The encryption technology is based on a relatively simple round, the cyclicity of which is 64 times.

64-byte block size.
The maximum length of the encrypted code is 33 byte.
Message digest parameters – 32 byte.
The default word size is 4 byte.
The number of repetitions within one cycle is 64.
The algorithm speed is 140 Mbit/s.

As mentioned earlier, the SHA-256 protocol is based on the Merkle-Damgaard concept, which means that it is first divided into blocks, and only then into individual words.

The set of information passes through a range of repetitions - 64 or 80. Each cycle is accompanied by the transformation of a block of words. The final hash code is generated by summing the initial values.

Cryptocurrencies with SHA-256 algorithm

Let's consider digital currencies, the mining of which is carried out according to the principles of the SHA-256 algorithm:

Bitcoin, a currency that needs no further introduction, remains the most popular crypto asset.
Peercoin - uniqueness lies in the fact that the code is created on the basis of Bitcoin, but the mechanism is used to protect the network, and PoW is used to distribute coins.
Namecoin is an open source technology that significantly improves security, privacy, and decentralization.
Unobtanium – characterized by minimal exposure to inflation. It will take about 300 years to mine Unobtanium coins.
Deutsche eMark is a digital network for the transfer of various assets, such as money. The exchange is carried out without intermediaries.
BetaCoin is an international means of payment that operates on the same principle as the Bitcoin system.
Joulecoin – provides the fastest possible confirmation of transactions, based on Bitcoin.
IXCoin is another open source project based on a peer-to-peer network.
– Blockchain platform that rewards users for publishing unique content.

It is also worth noting that the SHA-256 algorithm is used in the Litecoin system, but only in a subroutine. The Scrypt protocol is used for mining.

Cryptocurrency mining using the SHA-256 algorithm

Let's start with the fact that you can mine coins whose systems operate using this protocol in three ways:

ASIC.

The difficulty of mining directly depends on what kind of cryptocurrency we are talking about. However, in any case, it is ASIC devices that are characterized by the greatest efficiency, the main disadvantage of which is their excessively high cost.

On average, an ASIC miner costs about 100 thousand rubles (Asic Miner AVALON 821), but you can also purchase more expensive models, the price of which reaches half a million rubles (Asic Miner BITFURY B8 16NM 50 TH/S).

As for mining cryptocurrency on processors, this method is considered the least effective. Especially when it comes to the digital currency Bitcoin.

The most adequate solution is from video cards. On average, the cost of a profitable farm ranges from $1000-2000. Which video card should I choose for mining cryptocurrency using the SHA-256 algorithm?

If we talk about Nvidia, then the best solution would be a video card (1400 MH/s). Naturally, the direct competitor AMD is also not far behind; absolutely all Vega series cards are suitable for mining. The Radeon RX Vega video adapter provides mining at a speed of 1200 MH/S. This is the kind of equipment that should be preferred.

If you are looking for a cheaper option, then you can purchase a Radeon 7970, such equipment is capable of delivering up to 800 MH/s. Do not forget that in addition to video cards, other equipment is required to run the farm, for example, cooling radiators, power supply, RAM, etc.

Conclusion

That's all miners need to know about the SHA-256 algorithm. Of course, many modern cryptocurrencies use the Scrypt protocol, but mining the most popular coin (BTC) is still carried out according to this principle.

Hello friends.
In this article you will learn about what the SHA256 algorithm is, what its features are and what cryptocurrencies it is based on. The abbreviation of this algorithm stands for Secure Hashing Algorithm.

The Sha256 algorithm is one of the most popular mechanisms for data encryption, which is part of the SHA2 family of algorithms. This category of cryptographic algorithms was created in mid-2002. It was developed by the US National Security Agency.

SHA 2 is based on earlier types of hash functions, in particular SHA1, created in 1995. As of 2019, the SHA 2 family consists of several algorithms:

SHA-224;

SHA-256;

SHA-384;

SHA-512;

SHA-512/256;

SHA-512/224.

The latest updates to the family were the SHA-512/256 and SHA-512/224 hash functions, which appeared in the first quarter of 2012. But in the 3rd quarter of 2012, the release of the 3rd replenishment algorithms took place - SHA 3, which became more advanced.

How SHA 256 works

Algorithm Sha 256 performs the function of changing (converting) any kind of information into fixed-size values of 256 bits or 32 bytes. These values are called digital fingerprints. In further work, the obtained values are used to decrypt the information.

You can learn more about how the SHA-256 algorithm works in this video.

Mining sha 256

If you watched the video, you already know that SHA 256 is the Bitcoin hashing algorithm. It is worth noting that at the time of the creation of the BTC cryptocurrency, this method was one of the newest, so I used it in my project.

Due to the fact that in the period from 2009 to 2011, many cryptocurrencies were created, which were based on the Bitcoin code, they all used the same hashing algorithm - SHA 256. All these cryptocurrencies can be mined either using specialized equipment or through video cards and central processors.

As the price of BTC increased, the popularity of its mining also increased. Therefore, after a while, manufacturing companies appeared that began to create chips aimed at mining cryptocurrencies. The devices based on these chips were called ASIC (Application Specific Integrated Circuit).

In 2019, ASIC Miner is the most popular among miners. They are more productive and require less effort to configure compared to GPU processors (video cards). The most popular ASIC manufacturer is Bitmain, which produces the Antminer line. As of 2019, the most powerful devices for mining BTC and BCH are:

T2 Turbo+ (T2T+) Miner from the manufacturer Innosilicon;

T2 Turbo (T2T) Miner from the manufacturer Innosilicon;

Antminer S9-Hydro from the manufacturer Bitmain;

Ebit E10 18T from the manufacturer Ebang Communication;

DragonMint T1 from Halon Mining.

After cryptocurrencies based on the Scrypt algorithm began to gain popularity, companies began to produce devices for these coins.

The SHA 256 hashing function formed the basis of the very first cryptocurrency in the world - Bitcoin and many altcoins. Did you know that it was created long before the advent of cryptocurrencies and was intended for completely different purposes? Today we will look at the history of the algorithm, the principle of its operation, current problems and which cryptocurrencies use SHA256.

Story

The name of the algorithm SHA 256 is an acronym for Secure Hashing Algorithm. That's what the developer called it - the US National Security Agency. The algorithm is a hashing function. This means that its input is a volume of data of arbitrary length, and the output is a set of characters of a fixed length, called a hash.

One of the key features of hash hashing functions is irreversibility. We can get the hash by passing the original data through the function, but knowing the hash, we will not be able to get the original data. Thanks to this property, the function has become widespread in various services and applications where data protection is required. Every day we use the SHA 256 algorithm when visiting sites on the Internet. It includes an SSL security certificate, which is required to establish a secure connection to the site.

The algorithm is part of the SHA-2 family, developed on the basis of SHA-1, which appeared in 1995. Since its inception, sha256 has been extensively tested for its strength using cryptanalysis. Cryptanalysis tests the resistance of hash functions to two main types of attacks:

Finding collisions - detecting identical hashes with different input parameters. The success rate of this attack compromises the security of the digital signature using the current algorithm.
Finding a preimage is the ability to decrypt the original message using its hash. This attack compromises the security of storing authentication password hashes.

The analysis was first tested in 2003, but no vulnerabilities were found then. As time passed, computing power developed. In 2008, collisions were found for iterations SHA-512 and SHA-256. In September of the same year, a method for creating collisions was developed for 31 iterations of SHA256 and 27 iterations of SHA-512.

Obviously, the time has come to develop a new crypto-resistant function. In 2012, the NSA invented SHA-3. Gradually, the updated algorithm will displace its less crypto-resistant predecessors.

Mining on SHA 256

US law permits the use of SHA and similar hash functions as part of other protocols and algorithms in certain federal non-Secret information security applications. SHA-2 can be used by private and commercial organizations.

It's no surprise that it was used in cryptocurrencies. Miners collect all transactions into a block and then begin hashing it. When a hash value that matches the system rules is found, the block is considered ready to be attached to the end of the blockchain. The new block will be found by someone who can calculate hash values very quickly. The speed of calculations depends on the power of the equipment. Three types of equipment can be used to mine Bitcoin:

CPU (central processing unit);
GPU (video cards);
ASIC (Application Specific Device).

The Bitcoin network is designed in such a way that each new block must be found once every 10 minutes. The number of network participants is constantly changing, but time must remain constant. To ensure equal residence times, the system adjusts the computational difficulty depending on the number of miners. Cryptocurrencies have gained popularity recently, and the number of miners has increased greatly. To prevent blocks from being found too quickly, the complexity of the calculations also increased.

Bitcoin began to be mined on processors. Then, when their power became insufficient, they switched to video cards. Soon the video cards could no longer cope. Then ASICs were invented - special devices designed for calculations using the sha 256 algorithm. One ASIC is much more powerful and energy efficient than several video cards.

Enterprising miners are creating huge farms from ASICs. In addition to the high cost of the equipment itself, such a farm receives electricity bills of several tens of thousands of dollars every month. Now Bitcoin mining makes sense only on such industrial farms; a home computer or even a farm with several video cards will not be able to compete with them, and even recoup the electricity.

However, this is easy to calculate. There are calculators to calculate the profitability of mining on sha256. For example, https://www.coinwarz.com/miningprofitability/sha-256. Enter the hashrate of your equipment (computing power), energy consumption and its cost into the form, the service will calculate your profit.

Altcoins SHA-256

Let's look at the list and list of cryptocurrencies that work on sha 256.

Bitcoin Cash (BCH)

Separated from it on August 1, 2017. The block size in classic Bitcoin is 1 MB. The network has grown so much that all transactions can no longer fit into a block. This led to the formation of queues of transactions and an increase in fees for making payments. The community decided to introduce a new protocol, according to which the block was increased to 2 MB, some information began to be stored outside the blockchain, and the time frame for recalculating the complexity was reduced from two weeks to a day.

Namecoin (NMC)

It is a system for storing and transmitting name-value combinations based on Bitcoin technology. Its most famous application is the domain name distribution system, which is independent of ICANN and therefore makes domain repossession impossible. Namecoin was launched in 2011, it runs on Bitcoin mining software forwarded to the server where Namecoin runs.

DigiByte (DGB)

A cryptocurrency launched in 2013 with the goal of improving the performance of Bitcoin and Litecoin. DigiByte differences:

Low volatility is achieved due to the huge number of issued coins (up to 21 billion), which ensures their low cost and ease of use in calculations;
Faster transactions by doubling the block size every two years;
Low commissions or no commissions;
The mining process is divided into five algorithms that allow you to mine coins independently of each other. You can use ASICs for SHA-256 and Scrypt, video cards for Groestl and Skein, and a processor for Qubit.

The SHA 256 algorithm is the most common among cryptocurrencies. This was caused by the popularity and success of Bitcoin, and the desire of altcoin developers to create similar coins. The increase in computational complexity prompted miners to look for ways to mine more efficiently, which resulted in the emergence of ASICs.

SHA256 - short for Secure Hashing Algorithm - is a current hashing algorithm created by the National Security Agency - the US National Security Agency. The task of this algorithm is to perform certain values from a random set of data with a length that is fixed. This length is the identifier. The resulting value is compared with duplicates of the original data, which cannot be obtained.

The main area where the SHA256 algorithm is used is in various applications or services that are related to the protection of information data, where the Secure Hashing Algorithm has spread. The algorithm also mines digital currencies.

SHA-256 is a cryptographic hash function.
As we all know, when mining crypto coins, we solve the original problem using CPU or GPU processors. The processes are reflected in the program interface for the lane, for example, in the form of the line “Accepted 0aef41a3b”. 0aef41a3b is the hash. This is the decoding information that corresponds to the hashed code that will be received. To put it another way, this is a line of decrypted data, while the main virtual block of data includes thousands, or even millions, of such lines.

Code
This can explain the situation when you need to solve a huge number of problems before you can find the required block of your crypto coin. It turns out that there is a single chance in 1, 10, 100 thousand or even a million decisions that the string that is decrypted will have the exact value required to remove the lock, or it will be personal data (or block). It’s like a drawing, a game, but with equipment that can calculate the winning combination faster and better than any miner.

Many people think that to solve problems related to hash when using the SHA256 protocol, you will need powerful hardware?

Hardware

Yes, this is the case. The more computing power is used, the better, as the chances of mining cryptocurrency (SHA256 miner) increase. However, it is important to understand that a huge number of miners earn coins on SHA256. There are those who have the most powerful hardware. But you shouldn’t be upset, everyone has every chance to win. It's like a lottery draw; it's impossible to predict when fortune will smile! SHA256 mining is a fun and interesting process that allows you to earn virtual coins.

Technical principle of the algorithm
Zetacoin
Algorithm SHA256 is currently implemented in all ASIC miners operating on the market platform, while ASIC equipment for other mining hash functions is still only at the development stage.
In addition to Bitcoin, mines using the SHA256 algorithm are used in many other virtual clone currencies. For example, it is used by the altcoins Peircoin and Namecoin. Many people are interested when using SHA256, which cryptocurrencies are used.

The most relevant are the following:

Ocoin.
Tekcoin.
Zetacoin and others
Sha256 and Scrypt are algorithms. Everyone who understands the mining of virtual volutes understands that in order to earn any coin it is necessary to mine it (that is, download the software, run it and wait until the computer equipment starts working). So the whole point of mining is that the PC solves the most complex problems (hash functions) and the more the computer equipment works, the more currency will be mined.

And the tasks that a PC solves may not be structured in the same way - some are based on the SHA256 algorithm, and others on Scrypt (others have been developed, but these are the most relevant among miners). For example, the familiar Bitcoin is earned using the Sha256 algorithm, and the DogeCoin cryptocurrency is mined using Scrypt. To put it another way, different digital currencies use different algorithms. For what reason?

And here’s why - Sha256 turned out to be not difficult and today, a large number of special devices have appeared (they are called ASICs), which solve problems using this algorithm very quickly, faster than standard powerful processors, so these ASICs bring miners many times more cryptocurrency than conventional computer equipment. Below is a video in which you can understand the technical principle of the algorithm.

Features of the SHA-256 protocol

SHA256 has some advantages over other algorithms. This is the most popular mining algorithm among all existing ones. It has proven itself to be reliable for hacking (which does not happen often) and an effective algorithm for both mining problems and other purposes.

There are also disadvantages:

The main disadvantage of SHA256 currency is control by miners.
Those with enormous computing power receive the bulk of the crypto, which eliminates one of the main principles of virtual money - decentralization.

As investments began to be made in computing power for an industrial Bitcoin mine, the difficulty of mining increased significantly and began to require exceptional computing power. This disadvantage is corrected in other protocols, the most innovative and “tailored” for use in the mine of digital currencies, such as Script.

Even though SHA256 dominates the crypto market these days, it will weaken its influence in favor of the most reliable and modern protocols. SHA256 pools will lose ground. Thus, the SHA-1 algorithms no longer provide the required level of protection due to the likely development of collisions.

Cryptocurrencies SHA256, like SHA512, are most protected from this negative point, but there is still a possibility of risk development. Miner on SHA256, like any other hashing, is the process of solving some complex cryptographic problem that is generated by a mining program based on information received from blocks.

Mining using the SHA256 hash function can be carried out in 3 methods:

CPU.
GPU
ASIC.
In the mine, the hash sum is used as an identifier of blocks that are already present, and the creation of new ones based on those that are available. The lane process is reflected in the interface as “accepted f33ae3bc9...”. Where f33ae3bc9 is the hashed amount, the part of the data that is required for decryption. The main block includes a huge number of hash sums of this kind. That is, mining with the SHA256 algorithm means selecting the correct value of the hashed amount without stopping, enumerating numbers in order to create the next block. The more powerful the equipment, the greater the chances of becoming the owner of that very correct block: the speed of sorting through various kinds of amounts depends on the capacity. Because Bitcoin is built on the SHA256 algorithm, a competitive mine on it requires extremely large computing power.

This is due to the fact that the production of ASICs, namely a special circuit for a special purpose, is enough to mine cryptocurrency. ASICS make it possible to mine Bitcoins and other cryptocurrencies using the SHA-256 hash function more quickly, efficiently and inexpensively.

What other SHA–256 cryptocurrencies can be mined? SHA-256 is a classic for digital currencies: the main virtual currency, Bitcoin, is built on it. That is why this hash is used in Bitcoin forks: in Bitcoin cash, Gold, Diamond.

In addition to them, SHA-256 is also used in:

Steam.
Digibyte.
Peercoin.
Namecoin.
Tikkoin.
Ocoin.
Zetacoin.
Emircoin.
The algorithm is also used as a subroutine in the digital currency Litecoin, and the main algorithm for the mine there will be Scrypt.

Pseudocode hash: functions
Pseudocode
Pseudocode.
What makes Scypt-Jane different is that it supports more than 3 different stream cipher systems. And in order to form a clear understanding of the algorithm, you should familiarize yourself with the characteristics of the functionality. Main functions:

Salsa20/8.
ChaCha20.
Salsa6420/8.
First of all we have Salsa20/8. This is a fairly simple function, the main task of which is to receive a 192-byte string (of numbers and letters) and then convert it into a 64-byte Salsa20 (x) string.

Salsa20/8
Salsa20/8.
Salsa20 is two-component: stream encryption for data encryption and a compression function (Rumba20 algorithm), which is needed to compress a 192-byte string to a 64-byte one. To put it another way: a line can be larger than 64 bytes until it becomes 192 bytes, and the line will be compressed to 64 bytes. ChaCha20 has slight similarities with Salsa20: it is also a stream encryption, but it provides some additional features, for example, increased resistance to cryptanalysis.

Chacha20 also increases data shuffling per round. In other words, when mining digital coins as part of a pool, you will notice that one mining round can include either a short or long time period. The length of time it takes a mining pool to find a single block is partly determined by the better mixing offered by Chacha20 of Skript-Jane.

By the way, various factors influence the decrease in round time. Another important function for mixing information in Script Jane is Salsa6420/8. It is an improved version of Salsa20/8, and makes it possible to work with the highest byte blocks. In addition to these functions, Jane's Script also supports a number of hashes, including SHA256. The algorithm also supports its most innovative version, SHA512.

Hashing Example
Scheme
Scheme.
What is hashing? The idea of a hash is based on the distribution of keys in a standard array H. The distribution occurs by calculating a hashed function h for each element key. Based on the key, it helps to obtain an integer n, which will serve as an index for the array H. It is clear that you should come up with a hashed function that would give different codes for various objects. For example, if strings should be used as the key of a hashed table, then you can select a hashed function that is based on the following algorithm (example in C): int hash(char* str) (int h = 0; for (int i=0; i
Where m is the size of the hashed table, C is a constant greater than any ord(c), and ord() is a function that returns the character code (a number). You can create your own hash function for a specific data type. But the basic requirements for the function have been developed: it must arrange the keys among the cells of the hashed table as uniformly as possible, and it must be easy to find. Below is a table. It can be understood that the indexes of keys in a hashed table are the result of the h function that is applied to the key.

Key
Key.
The image also shows one of the main problems. With a fairly low value of m (the size of the hashed table) relative to n (the number of keys) or with a bad function, it can happen that 2 keys are hashed into a common cell of the array H. This is a collision.

Good functions tend to reduce the chance of collisions to zero, but given that the space of all possible keys may be larger than the size of the hash table H, it still cannot be avoided. But experts have developed a number of technologies to resolve collisions. Setting up pool SHA256 for coin mining is shown in the video. You can understand how to mine cryptocurrency.

SHA 256 - short for Secure Hashing Algorithm - is a popular cryptographic hashing algorithm developed by the National Security Agency. The purpose of SHA-256 is to make certain fixed-length values from a random set of data that will serve as an identifier for that data.

The resulting value is compared with duplicates of the original data, which cannot be extracted. The main scope of application of the algorithm is use in various applications or services related to information security, where the function has become widespread. It is also used as a technology for mining cryptocurrencies.

This algorithm belongs to the SHA-2 group of encryption algorithms, which in turn are developed on the basis of the SHA-1 algorithm, first created in 1995 for use for civilian purposes. SHA-2 itself was developed by the US National Security Agency in the spring of 2002. Within three years, the US NSA issued a patent for the use of SHA technology in civilian projects.

In 2012, the National Institute of Standards and Technology created an updated version of the algorithm: SHA-3. Over time, the new algorithm will replace both the current main SHA-2 algorithm and the already outdated, but still used SHA-1.

The hash sum is not a data encryption technology in the classical sense; this makes it impossible to decrypt data in the opposite direction. This is one-way encryption for any amount of data. All SHA algorithms are based on the Merkle-Damgaard method: the data is divided into uniform groups, each of which goes through a one-way compression function. As a result, the data length is reduced.

This method has two significant advantages:

fast encryption speed and almost impossible decryption without keys;
minimal risk of collisions (identical images).
Where else is it used?
Every day, every Internet user, whether they know it or not, uses SHA-256: the SSL security certificate that protects every website includes the SHA-256 algorithm. This is necessary to establish and authenticate a secure connection to the site.

Pros of SHA-256
SHA-256 is the most common mining algorithm among all others. It has proven itself to be hack-resistant (with rare exceptions) and an efficient algorithm for both mining and other purposes.

Cons of SHA-256
The main disadvantage of SHA-256 is its controllability by miners: those with the largest computing power receive the majority of the cryptocurrency, which excludes one of the fundamental principles of cryptocurrency - decentralization.

After large investors began investing in computing power for industrial Bitcoin mining, the difficulty of mining increased exponentially and began to require exceptional computing power. This drawback has been corrected in other protocols, more modern and “tailored” for use in cryptocurrency mining, such as Scrypt. Despite the fact that today SHA-256 occupies a large part of the cryptocurrency market, it will weaken its influence in favor of more secure and advanced protocols.

After some time, the SHA-1 algorithms no longer provided the required level of reliability due to the likely occurrence of collisions. SHA-256, like SHA-512, are more protected from this flaw, but the possibility of occurrence is still present.

Use in cryptocurrencies

Mining with SHA-256, as with any other algorithm, is the process of solving some complex cryptographic problem that is generated by a mining program based on data from previous blocks.

Overview of the SHA-256 encryption algorithm

There are three ways to mine using the SHA-256 function:

CPU (central processing unit);
GPU (graphics processing unit);
specialized processor: ASIC.
In mining, the hash sum is used as an identifier of existing blocks and the creation of new ones based on previous ones. The mining process is displayed in the interface as “accepted f33ae3bc9...”. Where f33ae3bc9 is the hash sum, the part of the data intended for decryption. The main block consists of a huge number of similar hash sums.

That is, mining with the SHA-256 algorithm is a non-stop selection of the correct hash value, enumeration of numbers to create a new block. The greater your computing power, the greater your chances of getting the correct block: the speed of searching through various hash sums depends on the power.

Due to the fact that Bitcoin is built on the SHA-256 algorithm, competitive mining on it requires extremely large computing power. This is due to the fact that for Bitcoin mining, the production of “ASICs” - application specific integrated circuit, i.e., a special-purpose integrated circuit, has been established for a long time. ASICS allow you to mine bitcoins and other cryptocurrencies using the SHA-256 algorithm much faster, more efficiently and cheaper.

Which cryptocurrencies use the SHA-256 algorithm
SHA-256 is a classic algorithm for cryptocurrencies: the main cryptocurrency, Bitcoin, is built on it. Accordingly, this algorithm is used in Bitcoin forks: Bitcoin Cash, Gold, Diamond.

In addition to them, SHA-256 is also used in:

Steemit;
DigiByte;
PeerCoin;
NameCoin;
TeckCoin;
Ocoin;
Zetacoin;
EmerCoin.
Also, the SHA-256 algorithm is used as a subroutine in the Litecoin cryptocurrency, and the main algorithm for mining there is Scrypt.

SHA is an abbreviation for Secure Hashing Algorhitm. It is a popular cryptographic hashing algorithm developed by the US NSA (National Security Agency).
This algorithm belongs to the SHA-2 family of encryption algorithms with a hash size of 224-512 bits, which in turn were developed based on the SHA-1 hashing algorithm with a hash size of 160 bits, first created in 1995 for use in civilian purposes (federal information processing standard FIPS PUB 180-1).

The SHA-2 family itself was developed by the US National Security Agency in the spring of 2002 (FIPS PUB 180-2, which included SHA-1). Within three years, NSA issued a patent for the use of SHA technology also in civilian projects (in February 2004, the SHA-224 hash function was added to FIPS PUB 180-2). In October 2008, a new edition of the standard, FIPS PUB 180-3, was released. In March 2012, the latest edition of FIPS PUB 180-4 was released, in which the SHA-512/256 and SHA-512/224 functions were added, based on the SHA-512 hashing algorithm (due to the fact that on 64-bit architectures, the SHA-512 function is much faster than the standard SHA-256, designed for 32 bits).

In 2012, the National Institute of Standards and Technology created an updated version of the algorithm: SHA-3 (Keccak). SHA-3 is a variable-width hashing algorithm. It was developed and published in 2008 by a group of authors led by Yoan Dymen, co-author of Rijndael, author of the MMB, SHARK, Noekeon, SQUARE and BaseKing algorithms and ciphers. On October 2, 2012, SHA-3 won the NIST (National Institute of Standards and Technology) cryptography algorithm competition. The competition itself was announced in November 2007, was created and held to complement and further replace the already outdated families of hash functions SHA-1 and SHA-2. On August 5, 2015, the new algorithm was published and approved as the new FIPS 202 standard. In the SHA-3 implementation, the creators report that it requires only 12.5 cycles per byte when executed on a regular PC with a processor similar to Intel Core2Duo. However, in fact, when implemented in hardware, Keccak turned out to be much faster than the other finalists of the competition. Over time, the new hashing algorithm will replace both the now obsolete but still sometimes used SHA-1 and the underlying algorithm, which is SHA-2.

How and why is SHA-256 used?
The purpose of this algorithm is to create certain fixed-length values from a set of random data that will serve as an identifier for this data. The resulting value is compared with duplicates of the original data, which cannot be extracted (decrypted) in any way. The main use of SHA-256 is its use in various services or applications related to encryption/decryption, as well as information security, where this function is very widely used. The SHA-256 algorithm is also used as a technology for mining several popular cryptocurrencies (Bitcoin, Steemit, DigiByte, PeerCoin, NameCoin and some others), but more on that below.

The hash sum is not a data encryption technology in its classical sense; this is what makes it impossible to decrypt data in the opposite direction. This is one-way encryption, in principle, for any amount of data and any type of data. All SHA algorithms are based on the Merkla-Damgard method: first, the data is divided into homogeneous groups, then each of these groups goes through an irreversible and one-way compression function, as a result of which the data length is significantly reduced.

The method has two significant advantages:

Fast encryption speed and almost impossible decryption without keys
Minimal risk of collisions (identical images).
Where else is SHA-256 used?
Every day, every Internet user, whether he knows it or not, uses SHA-256 almost every day: the SSL security certificate that protects almost all websites is based on the use of the SHA-256 algorithm. This is necessary to establish and authenticate a secure and secure connection to the site.

Pros of SHA-256

SHA-256 is the most common smart encryption algorithm among all others. It has proven itself to be hack-resistant (with rare exceptions) and an efficient algorithm for cryptocurrency mining tasks, as well as for other purposes.

Cons of SHA-256

The main disadvantage of the algorithm in the case of mining is its excessive control on the part of the miners: the owners of the largest computing power (mainly China) receive the majority of the mined cryptocurrency, which excludes decentralization as one of the basic principles of almost all cryptocurrencies.

Mining based on the SHA-256 algorithm
SHA-256 mining, like mining based on any other encryption algorithm, is the process of solving any complex cryptographic problem created by a mining program based on data from previous blocks.

Using SHA-256, you can mine in three different ways:

CPU (central processing unit) - the slowest and most disadvantageous method
Graphics Processing Unit (GPU)
ASIC (dedicated processor or integrated circuit) is one of the fastest and most cost-effective ways
During the mining process, the hash sum is used as an identifier of existing blocks and the creation of new blocks based on previous ones. The main block consists of a huge number of similar hash sums. Thus, mining using the SHA-256 algorithm is a non-stop process of selecting the correct hash value and searching for the values to create a new block. The greater the computing power of your equipment, the greater the chance of getting the correct block: the speed of searching hash sums directly depends on the capabilities of the equipment.

Due to the fact that Bitcoin mining, like some other cryptocurrencies, is based on the SHA-256 algorithm, extremely high computing power is required for competitive mining. This is due to the fact that ASICs and (Application Specific Integrated Circuits) have long been used to mine Bitcoin, that is, special-purpose integrated circuits that are designed only for one specific encryption algorithm. ASICs make it possible to mine Bitcoins faster and more efficiently (and cheaper) another cryptocurrency, the mining of which is based on the SHA-256 algorithm.

SHA-256 can rightfully be called a classic cryptocurrency algorithm, because “digital gold” - Bitcoin, as well as all its many forks (Bitcoin Cash, Gold, Diamond and others) are based on it.

SHA-256 is also used as part of the program code in Litecoin, one of the most popular cryptocurrencies, but the main mining algorithm is still Scrypt.

The original version of the SHA-256 algorithm was created by the US National Security Agency in the spring of 2002. A few months later, the National Metrology University published the newly minted encryption protocol in the federally accepted security standard FIPS PUB 180-2. In the winter of 2004, it was replenished with the second version of the algorithm.

Over the next 3 years, the NSA released a patent for the second generation SHA under a Royalty-free license. This is what gave rise to the use of technology in civilian areas.

Note! Quite an interesting fact: every user of the World Wide Web, without knowing it, uses this protocol during his travels on the Internet. Visiting any web resource protected by an SSL security certificate automatically triggers the execution of the SHA-256 algorithm.

This protocol works with information divided into parts of 512 bits (or in other words, 64 bytes). It performs a cryptographic “mixing” of it and then produces a 256-bit hash code. The algorithm consists of a relatively simple round that is repeated 64 times.

In addition, SHA-256 has quite good technical parameters:
Block size indicator (bytes) – 64.
The maximum permissible message length (bytes) is 33.
Message digest size specification (bytes) – 32.
The standard word size (bytes) is 4.
Internal position length parameter (bytes) – 32.

The number of iterations in one loop is only 64.
The speed achieved by the protocol (MiB/s) is approximately 140.
The operation of the SHA-256 algorithm is based on the Merkle-Damgard construction method, according to which the initial indicator immediately after the change is made is divided into blocks, and those, in turn, into 16 words.

The data set goes through a loop of 80 or 64 iterations. Each stage is characterized by the launch of hashing from the words that make up the block. A couple of them are handled by the function's instrumentation. Next, the conversion results are added up, resulting in the correct hash code. To generate the next block, the value of the previous one is used. It will not be possible to convert them separately from each other.
It is also worth mentioning the 6 bit operations on which the protocol operates:
“and” - bitwise “AND” operation;

“shr” - moves the value the required number of bits to the right;
“rots” - a command similar in action to the previous one, with the only difference being that a cyclic shift is carried out;
"||" or concatenation - the operation of connecting parts of a linear structure, most often strings;
“xor” is a command that removes “OR”;
“+” is an ordinary addition operation.

As you can see, this is a fairly typical set of operations for any encryption algorithm.

Cryptographic meaning of SHA-256

In order to determine the value of this algorithm, it is necessary to turn to cryptanalysis. This discipline finds methods for decrypting information without using a specialized key.

The first studies of SHA-256 for the presence of vulnerabilities began to be carried out by specialists in 2003. At that time, no errors were found in the protocol.

However, already in mid-2008, a group of experts from India was able to find collisions for 22 iterations of the SHA family of architectures. A few months later, a method was proposed to develop collisions for a truncated version of the protocol, and then for 31 iterations of hashing the SHA-256 itself.

When analyzing the convolution function, its resistance to 2 types of attacks is tested:
The presence of a preimage is the decryption of the initial message using its hash code. Resistance to this type of influence guarantees reliable protection of the conversion results.
Finding collisions - similar output data with different input characteristics. The security of an electronic signature using the current protocol directly depends on the resistance to this type of attack.
The creators of the second generation of the SHA algorithm decided that the new encryption mechanism would operate on the basis of completely different principles. Thus, in the fall of 2012, the protocol of the third series - Keccak - was born.

Practical application and certification of technology

United States law allows the use of SHA-256 and other similar hashing methods in certain government programs to protect information. In addition, the algorithm can be used by commercial companies.

Important! Therefore, it is not surprising that this protocol was used in the first digital currency. The issuance of new Bitcoin coins is accomplished by finding strings by their specified SHA-256 architecture.

How does this affect specialized devices for cryptocurrency mining? Each step in this algorithm has a fairly simple form - a primitive bit operation and a 32-bit addition (anyone who is familiar with the basics of circuitry can easily imagine what this looks like in hardware). Therefore, for ASIC miners to work effectively, you only need to have a dozen blocks for executing the stages of the algorithm.

In contrast to Bitcoin, Litecoin, Dogecoin and other similar “coins” use the Scrypt encryption protocol, which is equipped with a function for increasing complexity. During its operation, this algorithm stores 1024 different hash function values, and at the output it connects them and obtains the transformed result. Due to this, implementing the protocol requires incomparably greater computing power.

The SHA-256 protocol turned out to be too easy and today there are a whole lot of specialized devices (so-called miners) that successfully bypass it. With their advent, there was no need to mine on a processor or assemble farms from video cards, since ASIC devices allow their owners to earn much more. However, this also has a downside. The use of miners centralizes the cryptocurrency too much, which means that new hashing protocols need to be introduced. This algorithm became Scrypt - a much more advanced security mechanism that requires significant performance and therefore theoretically deprives special devices of a special advantage.

From the perspective of the average user, there is no difference between the SHA-256 and Scrypt protocols. You can mine digital currency with your computer or farm using any of these protocols.

The SHA-256 algorithm currently accounts for more than 40% of the total market, but there are undoubtedly others. And soon they will supplant their illustrious predecessor. Thus, among the relatively recent ones, it is necessary to mention the particularly “miner-resistant” Dagger protocol, which is going to be used in the decentralized Ethereum platform. Perhaps it will be he who will take the baton of leader in the field of hashing and take the place of SHA-256.

Since its inception, sha256 has been extensively tested for its strength using cryptanalysis. Cryptanalysis tests the resistance of hash functions to two main types of attacks:

Finding collisions - detecting identical hashes with different input parameters. The success rate of this attack compromises the security of the digital signature using the current algorithm.
Finding a preimage is the ability to decrypt the original message using its hash. This attack compromises the security of storing authentication password hashes.

Obviously, the time has come to develop a new crypto-resistant function. In 2012, the NSA invented SHA-3. Gradually, the updated algorithm will displace its less crypto-resistant predecessors.

Mining on SHA 256
US law permits the use of SHA and similar hash functions as part of other protocols and algorithms in certain federal non-Secret information security applications. SHA-2 can be used by private and commercial organizations.

CPU (central processing unit);
GPU (video cards);
ASIC (Application Specific Device).
The Bitcoin network is designed in such a way that each new block must be found once every 10 minutes. The number of network participants is constantly changing, but time must remain constant. To ensure equal residence times, the system adjusts the computational difficulty depending on the number of miners. Cryptocurrencies have gained popularity recently, and the number of miners has increased greatly. To prevent blocks from being found too quickly, the complexity of the calculations also increased.

Altcoins SHA-256
Let's look at the list and list of cryptocurrencies that work on sha 256.

Bitcoin Cash (BCH)
A fork of Bitcoin that separated from it on August 1, 2017. The block size in classic Bitcoin is 1 MB. The network has grown so much that all transactions can no longer fit into a block. This led to the formation of queues of transactions and an increase in fees for making payments. The community decided to introduce a new protocol, according to which the block was increased to 2 MB, some information began to be stored outside the blockchain, and the time frame for recalculating the complexity was reduced from two weeks to a day.

Namecoin (NMC)
It is a system for storing and transmitting name-value combinations based on Bitcoin technology. Its most famous application is the domain name distribution system, which is independent of ICANN and therefore makes domain repossession impossible. Namecoin was launched in 2011, it runs on Bitcoin mining software forwarded to the server where Namecoin runs.

DigiByte (DGB)
A cryptocurrency launched in 2013 with the goal of improving the performance of Bitcoin and Litecoin. DigiByte differences:

Low volatility is achieved due to the huge number of issued coins (up to 21 billion), which ensures their low cost and ease of use in calculations;
Faster transactions by doubling the block size every two years;
Low commissions or no commissions;

The mining process is divided into five algorithms that allow you to mine coins independently of each other. You can use ASICs for SHA-256 and Scrypt, video cards for Groestl and Skein, and a processor for Qubit.
The SHA 256 algorithm is the most common among cryptocurrencies. This was caused by the popularity and success of Bitcoin, and the desire of altcoin developers to create similar coins. The increase in computational complexity prompted miners to look for ways to mine more efficiently, which resulted in the emergence of ASICs.

Owners of huge ASIC farms have gained an advantage in mining and have deprived those who do not want to invest in expensive equipment of the meaning and desire to mine. All mining is concentrated in the hands of a few giants. The main principle of cryptocurrencies - decentralization - is under threat. Cryptocurrency developers understand this better than anyone else, so they strive to use algorithms in their blockchains that would be impossible to create ASICs for. Successful examples are Ethereum and Monero.

64-byte block size.
The maximum length of the encrypted code is 33 byte.
Message digest parameters – 32 byte.
The default word size is 4 byte.
The number of repetitions within one cycle is 64.
The algorithm speed is 140 Mbit/s.
As mentioned earlier, the SHA-256 protocol is based on the Merkle-Damgaard concept, which means that it is first divided into blocks, and only then into individual words.

SHA parameters

Cryptocurrencies with SHA-256 algorithm
Let's consider digital currencies, the mining of which is carried out according to the principles of the SHA-256 algorithm:

Bitcoin, a currency that needs no further introduction, remains the most popular crypto asset.
Peercoin - uniqueness lies in the fact that the code is created on the basis of Bitcoin, but the PoS mechanism is used to protect the network, and PoW to distribute coins.
Namecoin is an open source technology that significantly improves security, privacy, and decentralization.
Unobtanium – characterized by minimal exposure to inflation. It will take about 300 years to mine Unobtanium coins.
Deutsche eMark is a digital network for the transfer of various assets, such as money. The exchange is carried out without intermediaries.
BetaCoin is an international means of payment that operates on the same principle as the Bitcoin system.

Joulecoin – provides the fastest possible confirmation of transactions, based on Bitcoin.
IXCoin is another open source project based on a peer-to-peer network.
Steemit is a Blockchain platform that rewards users for publishing unique content.
It is also worth noting that the SHA-256 algorithm is used in the Litecoin system, but only in a subroutine. The Scrypt protocol is used for mining.

Cryptocurrency mining using the SHA-256 algorithm
Let's start with the fact that you can mine coins whose systems operate using this protocol in three ways:

CPU;
GPU;
ASIC.
Mining scheme

As for mining cryptocurrency on processors, this method is considered the least effective. Especially when it comes to the digital currency Bitcoin.

The most adequate solution is a farm of video cards. On average, the cost of a profitable farm ranges from $1000-2000. Which video card should I choose for mining cryptocurrency using the SHA-256 algorithm?

If we talk about Nvidia, the best solution would be the GTX 1080 Ti (1400 MH/s) video card. Naturally, the direct competitor AMD is also not far behind; absolutely all Vega series cards are suitable for mining. The Radeon RX Vega video adapter provides mining at a speed of 1200 MH/S. This is the kind of equipment that should be preferred.

SHA-256 algorithm for mining. The technical basis of cryptocurrency is currently of interest to many who are interested in such. Not everyone is familiar with the concept of “cryptography”. It is very difficult to understand everything that happens in the so-called Bitcoin protocol. But we will still try to do this in simple words.

SHA 256 hashing algorithm

Every user who works with the Internet has no idea that they work with this algorithm every day, every second. Each Internet resource is protected by an SSL certificate, which can only be visited when working with the SHA-256 algorithm.

The classic SHA-256 algorithm builds all Bitcoin mining. This is where the mining of other cryptographic currencies (altcoins) comes from.

SHA-256 is a cryptographic hash function. Main task: hashing data (random set) into a certain length value (“fingerprint”).

Using, the problem is solved using a specialized processor and video card. Using the program interface, users monitor the transformation processes. The algorithm actually finds the correct hash value.

The difficulty of mining lies precisely in the fact that choosing the correct hash (solving a specific problem) is only possible by searching through many problems. You will have to find not just some hash, but a number with a certain number of zeros at the very beginning. The chances that the value will be correct are very, very small. That is, the key parameter is the difficulty, which is set by the mining pool.

Mining SHA 256

You don't need to be an expert to understand the complexity of hashing in the SHA-256 protocol. Accordingly, miners have to use incredibly powerful equipment that will be capable of solving the above problems.

The more computing power is used, the greater the speed of mining digital coins.

Separately, it is worth noting that mining is a function that is performed by many specialists. And, naturally, their software can be much more productive. You shouldn’t be upset, since the hashing process is sometimes more like a lottery.

The SHA-256 algorithm in mining is implemented on every . But ASIC equipment for other algorithms is just being developed.

The SHA-256 algorithm is present in the mining process not only of bitcoins, but also of other cryptocurrencies.

Cryptocurrencies implemented on the basis of the SHA-256 algorithm are very actively gaining popularity today: Peercoin, Namecoin, Terracoin, Tekcoin, Ocoin, Zetacoin, PremineCoin and others.

The operation of the SHA-256 algorithm is quite difficult to understand, so it is better to concentrate on methods and effective strategies for mining cryptocurrency rather than trying to analyze the algorithm itself.