I remember when I was a kid, I was always looking to invent a new language so that when I was talking to my friends, the people around me wouldn’t understand what we were saying! I didn’t know anything about cryptography at that time, but the encryption of words was very interesting to me.
Cryptography is the knowledge by which people can store or transmit their information and messages securely; Cryptography in Greek is derived from two words kryptós meaning “secret, hidden” and graphein meaning “writing”.
Encryption was what I did, I would write a message to my friend and he could read it. This knowledge and art is thousands of years old; From World War II letters and telegraphs to bank cards and e-commerce and digital currencies, everyone has used this knowledge.
Where did cryptography begin?
When I was writing an encrypted letter, I used a little technique; We had a convention that each letter of the alphabet would be interspersed with other letters in a certain order. At first, we used to write the desired number and according to that number, we changed the alphabet letters.
For example: 3 <- "Athztpach tsashchazap" this phrase is coded, that is, each of the written letters must go back 3 letters to decode the desired sentence, if we do this, we will get the phrase "today's currency website" brought ^-^
This method in the distant past by Julius Caesar was famously used; With this method, he would encrypt a text and then be able to restore it to the previous state.
Much later in the 16th century, a person named Giovan Battista Bellaso, who was working in the field of cryptologist, the new method Vigenere cipher designed and became famous as the first method of encryption and cryptography with a key.
In this method, our text is encrypted using a word as a key and a table written in 26 rows of alphabet letters, and then delivered to the recipient.
After years passed and with the arrival of computers, cryptography and encryption algorithms became more complex than in the distant past; But the purpose of cryptography is the same: to transfer information and messages in an encrypted form between the source and the destination.
What is Cryptography?
As we said earlier, cryptography is the method by which information and messages are stored and finally transferred in a safe and secure manner; so that only the sender and receiver can read it.
In computer science, encryption is done through algorithms that are designed using the rules of mathematics, physics, engineering, etc. These algorithms encrypt messages and information in a way that cannot be easily decoded and read.
These cryptographic algorithms are used for digital signatures, internet searches, credit card transactions, emails, social media messages, smart contracts, digital currency wallets, public key cryptography, and the entire blockchain field.
Purposes of cryptography
The purpose of cryptography is to build algorithms and protocols that can create a secure and reliable platform for transferring information; This secure platform is built by important elements that all algorithms and protocols follow. These elements are:
1. Confidentiality
When data is encrypted, it means that data and information cannot be accessed by unauthorized persons.
2. Data Integrity
Data integrity refers to the concept that data should not be tampered with or altered while being sent or received.
3. non-repudiation
Non-repudiation means that the sender cannot deny or deny the sent information and the purpose of sending them.
4. Authentication
In order to be sure that the sender and receiver are sending and receiving information by encryption, authentication must be done.
Cryptographic algorithms
If we take a general look from the first encryption method to the latest type, we will notice that with the advancement of technology, the structure of sending information and messages in a secure and secret way has also become more advanced. Cryptographic methods were developed and now it can be said that they use three general algorithms for this work, which include symmetric algorithm, asymmetric algorithm and hash functions.
1. Symmetric cryptography
Symmetric encryption focuses on one key; That is, the sender and receiver share a public key with each other, which is used for encryption and decryption; Of course, this key will remain hidden between the origin and the destination.
This group of algorithms use the technique of data substitution and displacement for encryption; Some of the most famous symmetric algorithms are:
- DES
- 3 DES
- AES
2. Asymmetric cryptography
Asymmetric encryption uses two public and private keys to send and receive data. At the source of the information, i.e. the sending part, the data is encrypted with the public key and at the destination where the data is received, it will be decrypted using the private key.
The level of data security is significantly increased with asymmetric algorithms because the keys are connected to each other based on complex mathematical functions. People who have the public key can use it to encrypt information, but only the person who has the private key can decrypt the message.
This algorithm is used in electronic signatures, smart cards, digital currency wallets, etc. Some of these types of algorithms are:
- RSA
- ECC
- DSA
- Diffie-Hellman
- ELGamal
3. Hash functions
Data hashing is one of the algorithms that is widely used in the blockchain world. Instead of using public and private keys, hash functions use algorithms and mathematical relationships to hash data.
In these functions, it doesn’t matter if your data input is 5 characters or 50 characters, you will finally get a fixed-length string output; That is, you enter a variable-length string and then receive a fixed-length string.
Hash functions have 3 main components:
certain: Sending a constant input multiple times does not make a difference to the output.
Irreversible: They work one-way and it will be impossible to determine the input from the output.
separable: Two different inputs will never have the same output.
Among the uses of the hash function, we can refer to passwords on various sites; When you create your password, this password will be hashed in the site’s database so that users’ information is not compromised in case of an attack on the database.
Of course, another application that we mentioned earlier is the use of hash functions in blockchain. When a block is created in the blockchain, its information will be hashed and thus the data will remain secure. According to the main components of the hash function, we can say that this is why blockchain data never changes after being recorded.
Cryptography and cryptocurrency
We said that crypto in Greek means “secret”; And you see exactly the same word in cryptocurrency.
Since there is no regulatory body and specific rules and regulations in the field of blockchain and digital currencies, the topic of cryptography and cryptography helps to gain people’s trust so that they can enter the digital currency market more easily.
But why is cryptography important in the field of blockchain and digital currencies? And why do traders and investors love this feature?
Data in the blockchain has security and transparency; Such a feature can only be done using cryptography and data encryption, which ultimately leads to users’ trust. Considering that digital currencies use blockchain technology, it can be said that the main nature of cryptocurrency is cryptography.
For the first time, Satoshi Nakamoto introduced a cryptocurrency called Bitcoin to solve the problem of spending again, which he reached by using the topics of cryptography and blockchain; After that, Ethereum, smart contracts, digital signatures, hard forks of Bitcoin, etc. also continued this path to solve other problems.
final word
Cryptography and encryption of data can help us in sending information securely, we see these aids in many parts of our daily life today; For example, smart cards, e-mail, blockchain and bitcoin, and even the messages we send on some social networks are examples of the use of cryptography in our normal lives.
In simpler words, in our modern world where most of the information is moved digitally, the need for cryptography is felt more than ever to ensure the security and transparency of the data. With the advancement of algorithm technology, advanced encryption functions have been developed and now issues like cyber crimes and online violations can be prevented.
Cryptography written in the world of cryptocurrencies for the first time in today’s currency. appeared.
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