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In this article, you will learn about the differences between Symmetric Encryption and Asymmetric Encryption, how they work, and what are their benefits!
Today’s digital world considers data as one of its most vital possessions. Unfortunately, where advanced technology has brought luxury to our way of living, it also poses threats that can lead to dreadful incidents. Cyber attacks and cybercrimes have become highly prevalent in modern digital scenarios.
Therefore, to protect our crucial data from fraudulent activities, encryption is one of the major keys. When using the word encryption, you must have often heard people talk about symmetric and asymmetric encryption. Well, both of them are encryption techniques but with very different methodologies.
So in this blog, we will glance at symmetric encryption vs asymmetric encryption and how they are different from one another.
To find the actual difference between symmetric and asymmetric encryption, the first step is to understand both encryption methods.
Let us begin with it.
It is one of the oldest and still relevant encryption techniques. This encryption method uses a secret single key to encrypt and decrypt the information on the large-scale, making the process of data encryption for the large amounts of data, faster and easier.
The symmetric encryption method aims to secure secret, sensitive, or vital information while in transit or at rest. Several industries including defence, aerospace, banking, healthcare, and IT widely use symmetric encryption technique.
Symmetric encryption either uses a stream cipher or block cipher for the encryption and decryption of data. A stream cipher converts plain text into ciphertext using one byte of data at a time. Whereas block data converts the entire unit of plaintext leveraging a predetermined key length of 128, 192, or 256 bits encryption strength.
The symmetric encryption process starts by encrypting the plain text into cipher text using a secret key. The data is transferred to its destination once it is encrypted. Then the sender shares its secret key with the recipient, where they decrypt the data back to its original plain text form using a similar secret key.
The symmetric encryption technique is used worldwide for data security and transportation. Here are a few popular processes that use this technique:
AES encryption is one of the most common encryption standards mostly used in internet networks. It uses block ciphers of 128, 192, or 256 bits to encrypt and decrypt the data. The encryption procedure of AES is so complex that it is nearly impossible to crack this technique.
DES, or now the National Institute of Standards and Technology (NIST) is one of the oldest encryption algorithms. The algorithm breaks down the data to create 64-bit blocks. However, considering the current technology, it is easier to break this encryption method and hence is used by only a few private networks.
You might have heard the term TLS/SSL many times in your browser. It is a network protocol used to build a secure connection with the server-side. When a user accesses a server, symmetric keys are generated to encrypt and decrypt the data. So that it can be securely shared between the client and the server in that particular session.
IDEA is an open and free block-cipher algorithm which was first introduced in the 90’s as a replacement to DES. However, as AES came into existence and turned out to be more efficient, IDEA did not succeed much and remained useful only for research and unofficial purposes.
Here are some advantages of using symmetric encryption:
The symmetric encryption technique uses shorter key lengths as compared to asymmetric encryption, so they are much faster to execute.
Symmetric encryption algorithms such as AES are highly secure and nearly impossible to crack.
One of the significant benefits of symmetric encryption is that it can work with large-size files more easily and faster.
Here are a few demerits of symmetric encryption:
In this method, an insecure channel compromises the security of the process by transmitting the keys.
Digital signatures ensure that the message comes from a secure source. Unfortunately, symmetric encryption does not have any method for enabling digital signatures.
Contrary to symmetric encryption, asymmetric encryption is a process in which the data is encrypted using one key and decrypted using another. So the process involves the usage of two keys.
It is also known as public-key cryptography. This form of encryption is more secure than symmetric encryption. However, you need to remember two sets of keys for the right implementation of this technique.
Compared to symmetric encryption, asymmetric encryption technique requires two sets of keys for the entire process. This technique involves the use of both private key and public key.
The sender converts the plain text into cipher text using public key cryptography. After the data reaches its destination, the receiver decrypts the same data file using his private keys. The data is brought back to its original plain text form without theft of any information.
Following are some of the examples of this encryption technique:
RSA is one of the most prominent examples of this encryption technique. It generates a public key for the encryption part by multiplying two large-sized, random prime numbers together. It also generates the private key needed for decrypting the data from the same prime numbers.
Mostly used for digital signatures, people usually combine DSS with Digital Signature Algorithm (DSA). The sender uses their private key to sign a message digitally, and the receiver uses the sender’s corresponding public key to acknowledge that signature and receive the encrypted file.
Elliptic Curve Cryptography (ECC) is an alternative to RSA that uses a small size of key mathematical elliptic curves for the process of data encryption. This algorithm technique is hugely popular because of its use in cryptocurrency. In general, ECC is much faster than RSA.
This method is extremely vital in the history of encryption. It is a key exchange method where the two parties can share their keys with each other without physical interaction. Prior to this method, the sender and the receiver had to meet to exchange the keys with one another physically.
Some of the key benefits of this encryption technique are:
One of the most vital benefits of this technique is that it eliminates the key distribution process. Users do not need to send the public and private keys through public-key servers, which usually pose a higher threat.
Asymmetric encryption introduced digital signatures to the world. It allows users to digitally sign the message with their private key and verify the authentication of the generated file.
This method of encryption is more complex due to the use of two keys, making it safer. It uses one key for the encryption and the other for the decryption of files.
The Asymmetric encryption method too has some disadvantages such as:
As the process is complicated and uses large-sized keys, it takes more time to process the files with this method.
A big challenge that threatens the use of this encryption technique is that if a user loses their private key, there is no other way to decrypt the message.
Multiple applications leverage and find both of these techniques useful in the encryption processes. Let us differentiate between symmetric encryption vs asymmetric encryption using a table:
|Basis||Symmetric Key Encryption||Asymmetric Key Encryption|
|Usage of Keys||Only one symmetric key is used for the encryption and decryption.||Two different public and private keys are used for encryption and decryption.|
|Length of Keys||Based on the security requirement, the key size can range between 128 to 256 bits.||This encryption technique uses large-sized keys. The recommended key size for RSA is 2048 bits or higher.|
|Speed of Execution||As the process requires only a single key for both its operation, it is much faster than asymmetric encryption.||Due to complex mathematical processing, this technique usually takes more execution time.|
|Purpose||It is mostly used to transmit or transfer large chunks of data.||It is mostly used for smaller transactions. Basically, it is first used to establish a secure connection and then transfer files over it.|
|Security||It is less secure than asymmetric encryption as the secret key is shared in it.||It is safer than symmetric key encryption as there is no need for key distribution.|
|Algorithms||The algorithms used in symmetric encryption are AES, DES, 3DES, and IDEA, TLS/SSL.||The algorithms used in asymmetric encryption are RSA, DSA, ECC, Diffie-Hellman, and TLS/SSL|
People generally debate that one method is better than the other, depending upon their preference. However, now that you know the difference between symmetric and asymmetric cryptography, you will know each method has its place. If one is securer, then the other is faster and vice versa. So it is better to leverage them according to your application needs and enjoy their work of encryption.