Crypto Academy / Season 3 / Week 8 - Homework Post for [@stream4u] - Cryptography

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I'm happy to be part of professor @stream4u assignment, on his topic on Cryptograph, i really understood a lot of things behind the Cryptograph,
Thanks alot for this Wonderful opportumity and lesson.

Cryptography

CryptoGraphy is a word that comes from Greek, where CryptoGraphy consists of two syllables, first the word "Crypto" and the second "Graphein". "Crypto" which means to hide, while "Graphein" means writing. From the combination of these two syllables we can interpret, "hidden writing". Cryptography is a science that deals with mathematical techniques related to information security aspects, such as data confidentiality, data validity, data integrity, and data authentication. But not all aspects of information security can be solved by cryptography.

So CryptoGraphy can be interpreted as a science or art that learns about techniques to maintain the security of messages from third parties to prevent third parties from retrieving information, such as data authentication, data confidentiality, and data integrity and data validity. There are two techniques used in the CryptoGraphy process, encryption and decryption. Encryption is a process that converts a readable message (plaintext) into an unreadable message (already scrambled) so that it becomes an unreadable message (ciphertext). While the description is the opposite of encryption, which is a process that makes an unreadable message (random) a message that can be scrambled, and this process requires the same key as the encryption key.
Cryptography

This word is made up from Greek language

Cryptography = kryptós(means, hidden/secret) + graphein(means, to write)

It is the technology which is used to secure communication between any two person who are using an third party. Using this technology only sender and receiver will know the message. This process is done by using encryption and decryption. First, message from sender is encrypted into some code and this message only be read when it is decrypted which requires private key.

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This is a combination of two words which are crypto + graphy whereas crypto means secret and the graphy means writing, so basically cryptography is as a technological method of sensing a message that is secured among others or a person where by the sender hold a unique type of code that will encrypt the message before he send, before the receiver get access to the message he/she has to decrypt it using a specific key.

The encryption key and decryption key are two important elements that ensure successful encryption and decryption when it comes to blockchain cryptography. Cryptography is used in blockchain technology in various ways such as cryptography for security, wallets, network transactions, private messages on the network.

Cryptography

When there is an interaction between two different parties and a third party from outside is prevented from getting access to the information between the two parties, it is called cryptography. To be able to get access to this information, any outsider needs a private key before he can get access. This is because the information is taken through a process called encryption and the information needs to be decrypted using the private keys before any other party can get access to it.

Blockchain cryptography

Once a data has been entered into a block of a blockchain and validated, it cannot be changed again. This is possible because blockchain is protected via cryptography. As we discussed in last week’s class, each block is connected to another block within the blockchain through a cryptographic hash. Private keys are generated for every member of the blockchain network and they are only unique to that particular member of the blockchain.
Any attempt to change any of these private keys will result in a change in the cryptographic hash which will intend affect the whole blockchain making it invalid. This will therefore prompt the user that there is something wrong with the blockchain so that the user can fix it.

Each public key has a pair of private key. The hash algorithms in the blockchain makes sure that the private keys are not compromised for the public keys to function. So before information can be decrypted in a certain public key, you need the corresponding private key before the decryption is possible.

The addresses used to make transactions in the blockchain networks are generated as a result of the combination of the public keys and the hashes. The nodes connected to each can therefore make transactions because the address has been generated from the public keys and hashes. The hashing cryptography cannot be reversed.
By this I mean the public keys cannot be reversed to get the original input.
These public keys can be used at different places within the same blockchain network

When making cryptocurrencies transactions, the funds we send are encrypted and the message is send with a specific address. The receiver of this transaction will need the private key of this transaction before he can have access to it. Only the private key can be used to decrypt the funds sent to the receiver.

Digital signatures are basically used to confirm information. The information in a blockchain are verified as original or right through the digital signatures which are mathematical computations.
These digital signatures combine together with the private and public keys to make sure the information in the blockchain system is verified. After this process, only the receiver of the information can access it because only the receiver has the private keys.

Signature can’t be denied: When there is any misunderstanding about the signature, we can all be sure about the person who signed it because only that person is in possession of the private keys.

It is advisable that the public key is often attached to the document so that at any point of the blockchain it can be verified. This ensures transparency within the blockchain.

Singing of transaction

Signing a transaction simply means proving the authenticity of a transaction to the blockchain or the receiver of the transaction by adding digital signatures to the transaction using the necessary private keys.

The signing process can be done both manually and automatically. Some wallets automatically generate their own signed signatures by the use of the private keys they generate.
An example of this is the exchange wallet. Whilst on the other hand some wallets need multiple signatures before they can operate, this type of wallets the signatures are generated manually.

Types of crypto wallets

At the moment, there are various types of crypto wallets that can be used to store cryptocurrency, send and receive transactions on the blockchain network. There are four main types of crypto wallets namely; web wallets, software wallets, hardware wallets and paper wallets.

Web Wallets - These type of crypto wallets are very common and popular in the blockchain and crypto space because it is the most easily accessible and anyone can make use of it using any device with a web browser. Web wallets also known as online wallets are wallets that live on the web and requires a user to make use of an internet browser in other to have access the web wallet and interact with the web wallet. A clear example of a web wallet is myetherwallet which is a web wallet for storing and sending and receiving ethereum and ethereum-based tokens.

Software Wallets - These types of wallets does not live on the web, but requires the user to install the software wallets on the supported device which can either be mobile device or computer device. This means that software wallets are both mobile wallets which are installed on mobile devices, and desktop wallets which are installed on computers. Since a software wallet does not live on the web, it does not require internet connect to access them, however, internet connection is needed to process the transactions. A clear example of software wallets are trust wallet (mobile wallet), atomic wallet (both mobile and desktop wallet), exodus wallet (both mobile and desktop wallet), etc.

Paper Wallets - These types of wallets lives offline. It is regarded as one of the safest type of wallet because it does not connect to the internet. Paper wallets are printed on papers with the public and private keys. Cryptocurrency sent to a paper wallet is very secure if the paper wallet is in a secure and safe place.

Hardware Wallets - These types of wallets are very secure because it is a physical crypto wallet and does not by itself connect to the internet, instead, the hardware wallet is used to authenticate the transaction on gateway that is either a web interface or installed software interface on a supported device that connects to the blockchain network through the internet. Since hardware wallets are physical device, they store the keys securely in the chip of the device that is not exposed, and allows the wallet user to access the wallets securely.

Conclusion.
Blосkсhаin hаѕ аlrеаdу established itѕеlf as a tесhnоlоgу fоundаtiоn for рауmеnt ѕуѕtеmѕ, smart соntrасtѕ, аnd, in thе future, data mаnаgеmеnt, еlесtrоniс voting, access rightѕ authentication аnd confirmation, forecasting, оnlinе ѕеrviсеѕ, аnd securities trading.
However, as thе blockchain and, in раrtiсulаr, blockchain-based сrурtосurrеnсу gain in popularity, investors mау bе concerned аbоut riѕkѕ such аѕ hасkеr аѕѕаultѕ аnd different аttеmрtѕ to ѕсаm аnd ѕtеаl virtual сurrеnсу. All of this makes blосkсhаin ѕесuritу ѕееm likе a рrоmiѕing technology tо еxреrtѕ аnd dеvеlореrѕ.
Hоwеvеr, wе саn nоw rеgаrd сrурtоgrарhу аѕ the fоundаtiоn аnd fundаmеntаlѕ оf аѕѕuring the ѕесuritу of сrурtо соmрuting.

Thе blосkсhаin, whiсh runѕ thе system, iѕ built оn сrурtоgrарhу. Thе blockchain architecture bеliеvеѕ that nеtwоrk раrtiсiраntѕ' truѕt iѕ fоrmаlizеd аnd is bаѕеd on mathematical аnd economic соnѕidеrаtiоnѕ. Inѕtеаd оf the induѕtrу'ѕ trаditiоnаl реrimеtеr security, cryptography ensures ѕесuritу bу ensuring the transparency and vеrifiаbilitу of аll actions.

Vаriоuѕ сrурtоgrарhiс аlgоrithmѕ ensure thе immutability of the blockchain transaction lоg, ѕоlvе thе аuthеntiсаtiоn problem, and rеgulаtе ассеѕѕ to the blockchain's nеtwоrk аnd dаtа аѕ a whоlе.