What you are going to read about in this article:
- What does Cryptography do?
- The meaning of Cryptography
- The history of Cryptography
- Who made Cryptography?
- How does Cryptography work?
- Advantages of Cryptography
- What is Symmetric encryption?
- Asymmetric encryption
- Hash functions
- Digital Signatures
- Cryptography and Crypto
What does Cryptography do?
Cryptography lets digital assets be traded and verified without the requirement of a trusting third party. Cryptography places the “crypto” in cryptocurrency. It has existed much longer than our digital age and has developed gradually, just like languages over the centuries.
The meaning of Cryptography
Cryptography is the science of making the information safe and secure by changing it into a form that only intended recipients can perform and read. The first known usage goes back to the year 1900 BC. Since hieroglyphics in an Egyptian tomb. The term itself comes from the Greek words kryptos and graphein. which means hidden and to write.
The history of Cryptography
One of the most well-known employment was developed by Julius Caesar around 40 BC. And it was appropriately named Caesar’s cipher. A cipher uses a secret piece of information that shows you how to get up and make an effort. Therefore unscramble a message. Caesar used a substitution cipher. To demonstrate each letter of the alphabet was replaced by a letter in a different fixed position further up or down in the alphabet. For example, the alphabet can be moved into five places to the right. The meaning of the letter “A” would now be “F”, “B” would now be “G” and … This showed us that he could transfer messages without having any fear that they would get translated. for the reason that it was only his trusted people that knew how to restore the message.
Who made Cryptography?
Giovan Battista Bellaso was a 16th-century cryptologist. He designed the Vigenere cipher (But, by mistake it attributed to diplomat Blaise de Vigenere). We believed he is the first cipher that used an encryption key. He wrote the alphabet across 26 rows, with each row changing a letter to create a grid. He wrote the encryption key out to match the length of the message. After that, the grid was used to encrypt the message, letter by letter. At last, the sender shared the encrypted message and the secret keyword to the recipient, who would have access to the same grid.
Then we had computers, which allowed much more sophisticated cryptography. However, the goal stays the same. It is to transfer a readable message (plain text) into something an unintended reader cannot understand (ciphertext). We know the process as encryption and also it is how information can be shared across public internet connections. The information about how to decrypt, or unscramble, the data is known as the key and only intended parties should have access to this information.
How does Cryptography work?
There are many ways in which to encrypt information, and the levels of complexity depend on the degree of protection the data may require. But we commonly see three types of cryptographic algorithms.
Advantages of Cryptography
By using cryptographic knowledge we can:
- Ensure the confidentiality of information
For example, James wants to send a message to Anne. If James’s message is normally transmitted to Anne, anyone on the message path can know the contents of the message. Using cryptographic technology, James can encrypt his message and send it to Anne. Anne receives James’s message in encrypted form. But can Anne unlock the message?
So before sending the message, James must teach Anne how to unlock the encrypted message. In fact, James and Anne have to agree to both use the same cryptographic protocol. From now on, all of James’s messages will be sent to Anne in secret.
2. Make sure the message is sent by the sender of the message
In the previous example, suppose Anne waits to receive a message from James and receives a message. Can Anne be sure that the sender of the message is James? Anne can use James’s knowledge of cryptography and digital signature to verify that the sender of the message was James. Of course, it should be noted that this is in a situation where James has used his digital signature to send the message.
3. Make sure the sender does not change the message on the network
Consider the circumstances in which James wants to receive his money from Anne and sends his bank account number to Anne in a message. It is possible that someone will see this message and change James’s account number and leave his account instead and deliver it to Anne. But if James sends his message using cryptographic technology, even if someone sees it along the way, he can not change its contents.
4. Prove that the sender sent the message
Now suppose James sends a message to Anne. Anne read the message and acted on James’s request. The next day, James denies sending a message to Sara. Cryptographic technology helps us to avoid this problem.
What is Symmetric encryption?Symmetric encryption or we can call it secret-key encryption, depends on a single key. This shows that the sender and receiver of these data, of them, share the same key. After that, they used both to encrypt and decrypt the information.
To perform such an act, the secret key requires to be agreed upon ahead of time. While it is still a good source of encryption. The fact that there is only a single key keeping the information safe. It means there is some risk as sending it over unsure connections. Just think that you want to share your front door key with a friend by hiding it under your doormat. Your friend will have access to your house. But there is also the chance that a stranger finds the key and enters your house without your permission.
Asymmetric encryption – or public-key encryption – uses a pair of keys. This added level of security instantly increases the protection of the data. In this case, each key serves a single purpose. There is a public key that can be exchanged with anybody, over any network. This key has the information on how to encrypt the data and anyone can use it. But there is also a private key. The private key is not shared and holds the information about how to decrypt the message. Both keys are generated by an algorithm that uses large prime numbers to create two unique, mathematically linked keys. Anyone with access to the public key can use it to encrypt a message, but only the private key holder can decipher the message.
It works very nearly like a mailbox. Anyone can put a message into the deposit gap. However, only the owner of the mailbox has the key to open it and read these messages. This is the basis for most cryptocurrency transactions.
Hash functions are another way cryptography can secure information. But instead of using keys, it relies on algorithms to turn any data input into a fixed-length string of characters.
Hash functions also differ from other forms of encryption because they only work one way, meaning you cannot turn a hash back into its original data.
Hashes are essential to blockchain management because they can encrypt large quantities of information without compromising the original data. Having an organized way to structure data not only increases efficiency, but hashes can also act like digital fingerprints for any data that’s been encrypted. This can then be used to verify and secure against any unauthorized modifications during transport through networks. Any changes to the original data would result in a new hash, which would no longer match the source and therefore would not be verifiable on the blockchain.
A digital signature is another key aspect of ensuring the security, authenticity, and integrity of data in a message, software, or digital document. As their name suggests, they act similarly to physical signatures and are a unique way to bind your identity to data and therefore act as a way to verify the information. But rather than having a unique character to represent your identity like with physical signatures, digital signatures are based on public-key cryptography.
The digital signature comes as code, which is then attached to the data thanks to the two mutually authenticating keys. The sender creates the digital signature by using a private key to encrypt the signature-related data, with the receiver getting the signer’s public key to decrypt the data. This code acts as proof that a sender created a message and it has not been tampered with while being transferred, and it ensures that the sender cannot deny they sent the message.
If the recipient is unable to decrypt and read the signed document with the provided public key, it shows there was an issue with the document or signature, and so the document cannot be authenticated.
Cryptography and Crypto
A large draw of cryptocurrencies is their security and transparency on the blockchain. All of that relies on cryptographic mechanisms. That is how most blockchain-based cryptocurrencies maintain security, and therefore it constitutes the very nature of cryptocurrencies.
It was on a cryptography message board back in 2009 that Bitcoin creator Satoshi Nakamoto suggested a way to solve the double-spend problem that had long been the Achilles heel of digital currencies. The double-spend problem occurs when the same unit of crypto has the potential to be spent twice, which would destroy trust in them as an online payment solution and make them essentially worthless.Nakamoto proposed using a peer-to-peer distributed ledger that was timestamped and secured by cryptographic means. That led to the creation of the blockchain as we know it today. As with all technology, cryptography will evolve to keep up with the demands for a secure digital environment. This is especially true with the growing adoption of blockchains and cryptocurrencies across industries and borders.