Symmetric Encryption vs. Asymmetric Encryption – How It Differs?

Here’s A General Difference Between Symmetric and Asymmetric Encryption

In this digital age, where online communication is one of the primary resources, attacks like a data breach, data tampering, and other online cybercrime is reaching the new heights, cybercrime is no different, in the realms of evolving technology. In order to keep users safe from these incidents, active security measures are needed to safeguard information. Among security measures, encryption is one of the old-age techniques, which is employed for the security of the information and to name a few – Symmetric and Asymmetric encryption are among them.

To further discuss these two, symmetric and asymmetric encryptions, let’s first start with the basics of both the encryption techniques and then we’ll get into the core part of this discussion, i.e., the comparison of the two.

What’s Symmetric Encryption?

Symmetric encryption is one of the most straightforward encryption techniques in which only one secret key is involved in ciphering and deciphering the information. In other words, Symmetric encryption is one of the encryption methodologies, which uses a single key for both encrypting as well as decrypting. It’s one of the old encryption methods in which secret key can be – a word, number, or a string of random letters.

Moreover, the most common usage of the symmetric encryption comes into the picture when an already encrypted connection is negotiated among a server and a client, which have an SSL/TLS certificate installed. Here, after the negotiation of the SSL connection, two-session keys of 256-bit are created and shared so the encrypted connection can occur.

Caesar’s Cipher is one of the popular examples where symmetric encryption is used. However, some of the modern approaches of the symmetric encryption are Blowfish, RC4, RC5, RC6, DES, and AES. And, among this AES-128, AES-192 and AES-256 are the most widely used algorithms.

Nonetheless, it does have the disadvantage that all the involved parties must exchange the secret key, which is used for encrypting the data before it can be decrypted.

What’s Asymmetric Encryption?

Compared to Symmetric encryption, Asymmetric encryption is new. It’s quite complicated, and unlike Symmetric encryption, Asymmetric encryption makes use of two different cryptographic keys commonly called – Public Key & Private Key for implementing data security.

Among these two public and private keys, as the name implies, the public key is publicly available to anyone, whereas the private key is kept secretly by the owner, which is further used only for decrypting the message. Also, the encrypted message can only be decrypted using a private key from the key pair.

Nevertheless, asymmetric encryption is used for day-to-day communication channels over the internet. Some of the popular asymmetric encryption algorithms are such as PKCS, RSA, DSA, ElGamal, and Elliptic curve techniques. And among these algorithms, RSA and Diffie-Hellman are widely used.

Understanding Public Key Encryption in Details.

Here’s How Asymmetric Encryption is Used with Digital Certificates

That said, to make use of asymmetric encryption, there should be a method to recognize the public key and digital certificates (SSL/TLS certificates) is one of the typical examples for that as it’s used in the communication of client-server. Here, the certificate comes in an information package that helps identify a user and a server. The information it includes is – the name of the organization, the organization who issued the certificate, and other details of the user like email address, country name, and the public key.

So, whenever a client and a server need a secured encrypted communication, they’ll send a query to the third-party via the network, which will send back the certificate’s copy from which other party’s public key can be extracted. Moreover, that certificate is also helpful for uniquely identifying the holder.

SSL/TLS certificates are one of the examples, which use both asymmetric as well as symmetric that are digitally signed and issued by trusted CAs (Certificate Authorities) like Sectigo, Comodo, Thawte, RapidSSL.

Let’s see in detail how Symmetric and Asymmetric encryption differs from each other by having a side by side comparison table of Symmetric Encryption vs. Asymmetric Encryption.

Factors	Symmetric Encryption	Asymmetric Encryption
Cryptographic Keys	Symmetric encryption consists of only one cryptographic key (also called a shared secret key) for both encryptions as well as decryption.	Asymmetric encryption has two different cryptographic keys, the public key, and private key pair.
Difficulty	Compared to Asymmetric encryption, symmetric encryption is quite easy to use as it has the only key to operate both the operations.	Due to two separate keys for processing encryption and decryption, asymmetric encryption is quite complex.
Execution Speed	Symmetric encryption is fast because of the single cryptographic key for both the operations.	Asymmetric encryption is a bit slower because two different keys are assigned to operate different operations, encryption, and decryption.
Used Algorithms	QUAD DES 3DES RC4 AES	Diffie-Hellman ECC DSA El Gamal RSA
Hardware	Suitable for performing simple algorithms that require economical hardware.	Suitable for complex and time-consuming algorithms that need powerful hardware.
Functionality	Offers secured communication between two parties in a closed ecosystem.	It provides hard to implement security in a way which is not mostly possible by symmetric encryption.
Purpose	Symmetric encryption is mostly used for the transmission of bulk data.	Asymmetric encryption is mostly used for securely exchanging secret keys.

Other Use Case of Symmetric & Asymmetric Encryption

Messaging Apps

Messaging apps such as Signal and WhatsApp depends on end-to-end encryption for safeguarding the confidentiality and privacy of user’s communication as well as authenticating the user.

Here end-to-end encryption, which helps keep the messages safe from unauthorized third parties, including the vendors, makes use of both symmetric and asymmetric encryption. Asymmetric encryption comes into action at the time of initializing encrypted conversation between the users, whereas symmetric encryption comes in for the duration of the communication.

Closing Thoughts

In today’s digital world, usually, both Symmetric and Asymmetric Encryption has essential roles for keeping communication and sensitive information secure. Though both are used, each of them has a certain advantage as well as disadvantage. Therefore, symmetric, as well as asymmetric encryption, is used for different applications.

Moreover, when it comes to securing online sessions using encryption, the latest algorithms are the best fit for it. Usually, the most recent encryption algorithms must be prioritized depending upon the task. Moreover, new algorithms are developed for reducing online threats such as eavesdroppers for securing information and enhancing confidentiality. So, it’s rightly said that users will get more updates from the cryptographic community in the coming time.