Encryption of information when we browse the Internet is essential to protect our activity, the information we exchange, the data we publish, etc.
In addition, it is a system widely used by the applications we usually use, but we sometimes need to understand how they work. Through this article, we will learn the basic concepts, the types of encryption and how information encryption works on the Internet.
What is Cryptography?
Cryptography is a reasonably old technique that seeks to encrypt a text or information so that only the sender and receiver can decrypt it. Within computing, cryptography is based on complex mathematical algorithms responsible for encrypting messages.
In addition, there are four basic requirements or objectives that cryptology must offer:
– Privacy or confidentiality: Only those people who are authorized to obtain it can access the information.
– Integrity: The message’s recipient must be able to verify that it has not been modified during its journey.
– Authentication: When secure communication is established between two interlocutors, each must be able to verify the other party’s identity irrefutably.
– Non-repudiation: None of the interlocutors must be able to subsequently deny that they have carried out a specific action or that they have transmitted certain information.
What types of encryption exist?
The two main types of encryption are symmetric encryption and asymmetric encryption.
– Symmetric cryptography: uses the same key to encrypt and decrypt the message, which both the sender and the receiver must previously know.
– Asymmetric cryptography: it is based on the use of two keys.
o The public one can be spread, without any problem, to all the people who need to send you some encrypted information.
o The private one, which should never reveal.
Let’s see it with an example, if we want three colleagues to send us an encrypted file, we must send them our public key (which is linked to the private one), and they can send us, confidentially, that file that only we can decrypt with the private key.
Although it may seem that could discover the private key could discover the vital private thanks to the public key, this is not the case. Complex algorithms are used to generate the keys, which are highly resistant to attack by cybercriminals.
Another purpose, widely used, is to be able to sign documents. In this way, the sender is certified, signing with the private key and verifying the recipient’s identity with the public one.
What are the advantages and disadvantages of one method or another?
Well, we already know how the two types of encryption work, but is one better? What are the advantages and disadvantages of each? To answer these questions, we can look at it from three perspectives:
– Speed :
o The main advantage of symmetric encryption is that it is much faster and more agile. So if you want to encrypt a large amount of information, you will save time with this type.
o In contrast, asymmetric encryption is much slower. If performance is a crucial factor, there are better options than this.
– Security :
o Symmetric encryption is not so secure since communicating the key supposes a significant vulnerability. It is essential to find safe means to communicate.
o The advantage of asymmetric encryption is that it can securely communicate public keys to third parties. This type is free to hand over the public key, while the private key remains with the user.
– Number of keys :
o Key management is also a benefit when using asymmetric encryption. You only need one key pair per user for each to be able to encrypt messages for all other users.
o As we saw with symmetric encryption, the number of users increases, and the number of keys increases.
How is encryption used to protect our information on the Internet?
When we use our equipment or browse the Internet, information encryption is very present to protect our privacy and information, for example:
– When entering websites whose URL begins with “HTTPS“, a ‘public’ key and a ‘private’ key are used to encrypt the data. When a browser initiates an “HTTPS” session with the web server, the web server sends the public key to the browser and an “SSL Handshake”, also known as a “hello”, is carried out between the browser and the server.
Once the secure connection has been initiated and accepted, the browser recognizes the link. It shows it as secure, either with a green bar or a padlock depending on the type of certificate used.
– There are many tools and software that allow us to protect the data on our devices. One example is the Windows BitLocker tool (preinstalled on Windows for Education, Pro, and Enterprise editions), which uses encryption algorithms to encrypt the contents of a drive, preventing unauthorized access.