Encryption is one of the main tools for keeping us safe when surfing the Internet or using different applications. Encryption helps us protect and keep our activity, the information we share, and our personal and session data secure.
What is encryption?
Encryption can be included within cryptography. It is a technique for encrypting or encoding texts or information so that they are only accessible by the sender and receiver. This technique uses complex mathematical algorithms to encrypt information in computer science and cybersecurity. To consider that information or text has been encrypted, it must meet a series of requirements or characteristics:
- Privacy: Information is only accessible to authorized persons.
- Integrity: The information has not been modified by any external agent. It must be kept intact from when it is received until it is delivered.
- Authentication: Verifying the other party’s identity within this information exchange must be possible.
- Non-repudiation: Either party can deny that it has transferred such information.
This is why encryption is one of the most popular and effective data security methods companies use.
Types of encryption
Within the world of cryptography, we can differentiate between two types of encryption: symmetric and asymmetric.
Symmetric encryption
Symmetric encryption, also called secret key cryptography, is a cryptographic method that uses the same key to encrypt and decrypt messages at the sender and receiver. Once both parties have access to this key, the sender encrypts a message using the key, sends it to the recipient, and the recipient decrypts it with the same key. It is the oldest form of encryption and is still relevant because of its data transmission speed. The encryption algorithms used for this type are Blowfish, RC4, DES, AES-128, AES-256, etc.
Asymmetric encryption
Asymmetric encryption, also known as public key cryptography (PKI), is a cryptographic method that uses two public and private keys to transfer data and information. In asymmetric encryption, the sender uses the public key to encode information in an unreadable form, which can only be decrypted or read with a secret key. When sending encrypted data from the public key scheme, the receiver needs a hidden key to access the encrypted data. Some of the most used algorithms for this type of encryption are DSA, RSA, PKCS, and EIGamal.
Differences between symmetric encryption and asymmetric encryption
Some of the differences between these two types of encryption have already been explained in their definition. Let us comment on them:
Security
Symmetric encryption is older and uses only one key, which must be communicated with the risk that this entails. However, asymmetric encryption uses two keys and securely communicates the public key to third parties. Although asymmetric encryption is more secure, a priori, each case will have to be looked at individually, and the combination of both ciphers is very interesting.
Speed
Asymmetric encryption, which is more complex, requires more time in its encryption and decryption processes than symmetric encryption. However, some organizations opt for symmetric encryption because it is faster.
Number of keys
Key management is also a benefit of using asymmetric encryption. You only need one key pair per user to encrypt messages for all other users. As we saw with symmetric encryption, as the number of users increases, the number of keys increases. Asymmetric encryption is better when encrypting communications with a large volume of data in transit. On the other hand, symmetric encryption is usually used to transmit small volumes of data in authentication systems.