A Beginner’s Guide to Data Encryption and its Relevance

Data Encryption Definition

Defining data encryption is rather simple; it’s all about translating data into another form, basically codes in such a way that it can be accessed only by people who have what’s known as a decryption key (or password). Data encryption is today one of the most effective methods of data security.

While unencrypted data is known as plaintext, encrypted data is referred to as ciphertext. The two main types of data encryption are- symmetric encryption (involving usage of one secret key) and asymmetric encryption (or public key cryptography), which involves using two keys to encrypt plain text.

Why data encryption?

The main purpose of data encryption is data security; it serves to protect the confidentiality of digital data that is stored on computer systems or transmitted in one way or the other- via the internet or from a network (or device) to another.

The modern encryption algorithms, which include key security initiatives like authentication (verification of the origin of a message), integrity (ensuring that the contents of a message remain unchanged once it’s sent) and non-repudiation (ensuring that the sender cannot deny sending the message), ensures data confidentiality very effectively.

Data Encryption: How it works

The process of encryption, as already mentioned, converts plain text into what we call ciphertext and is carried out by means of an encryption key plus encryption algorithm.

The symmetric encryption, which is much faster than the asymmetric one, works by using the same secret key for encryption as well as decryption. Thus, the sender would have to exchange the encryption key with the recipient also. Today, as managing and exchanging huge quantities of key seems risky, many data encryption services endeavor to secure it further by using an asymmetric algorithm to exchange the secret key once the data is encrypted using a symmetric algorithm.

Asymmetric encryption, as we have already mentioned, works by using two different keys- the public key (which is shared with everyone) and the private key (which is private and protected). Thus, data that is encrypted using the public key can only be decrypted with the private key. The RSA algorithm, which is a popularly used asymmetric cryptography algorithm, is named after Rivest (Ron Rivest), Shamir (Adi Shamir) and Adleman (Leonard Adleman) of the Massachusetts Institute of Technology, who first described it in 1977. This asymmetric key algorithm, which is based on the fact that it is difficult to factorize a large integer, would work with a public key comprising two numbers where one number is the multiplication of two large prime numbers, and a private key, which is also derived from the same two prime numbers. The key size is usually increased to make it tough to factorize the number and compromise the private key. RSA algorithm is widely used as it allows for the use of both the public and private keys to encrypt a message and thereby, through digital signatures, helps assure the confidentiality, integrity, authenticity, and non-repudiation of all transmitted data.

Why ensuring secured encryption is of critical importance…

Cybercriminals today seek to attack and steal encrypted data too, using different modes of attack. The most popular mode is the brute force attack, which employs using random keys until the hackers find the right one. Side-channel attacks (based on information gained from the implementation of the cipher), and cryptanalysis (executed by finding and exploiting a weakness in the cipher) too are methods used to attack encryption.

To avoid brute force attacks, it’s always best to keep in mind that encryption strength is directly proportional to key size.

Since cybercriminals seek to use different methods to target and attack encryption and encrypted data, we always need to use data protection solutions to encrypt devices, email and data. Today, in every organization, employees use personal devices and many other external devices, removable media etc. They also depend on various web applications to carry out their work. Hence organizations must use data loss prevention solutions to prevent malware attacks and data theft. This must be done not only keeping in mind the organizational network, but all external, removable devices plus the web and cloud-based applications as well. The organizations must ensure auto-encryption of data at all levels and even after it leaves the organization. Similarly, since today employees in a firm work and collaborate via email, encrypted email communication is also of critical importance. The data in all emails and attachments need to be encrypted.

Thus, organizations can use effective data loss prevention software that would ensure proper data encryption at all levels, thereby ensuring comprehensive data security.