Symmetric and Asymmetric Encryption

What is Encryption?

Symmetric Key Algorithm

above figure will help you to think more efficiently

Need of Symmetric key algorithm?

  • Payment applications, such as card transactions where PII needs to be protected to prevent identity theft or fraudulent charges.
  • Validations to confirm that the sender of a message is who he claims to be.
  • Random number generation or hashing.

Traditional Symmetric Ciphers

Table of distribution of traditional ciphers.
  • f -> g
  • o -> p
  • l -> m
  • w -> x

Asymmetric key algorithm

above figure will help you to think more efficiently

What is asymmetric key algorithm?

box type example of the asymmetric key algorithm.
  • Plain Text:
    This is the message which is readable or understandable. This message is given to the Encryption algorithm as an input.
  • Cipher Text:
    The cipher text is produced as an output of Encryption algorithm. We cannot simply understand this message.
  • Encryption Algorithm:
    The encryption algorithm is used to convert plain text into cipher text.
  • Decryption Algorithm:
    It accepts the cipher text as input and the matching key (Private Key or Public key) and produces the original plain text
  • Public and Private Key:
    One key either Private key (Secret key) or Public Key (known to everyone) is used for encryption and other is used for decryption
  • Public key Encryption is vulnerable to Brute-force attack.
  • This algorithm also fails when the user lost his private key, then the Public key Encryption becomes the most vulnerable algorithm.
  • Public Key Encryption also is weak towards man in the middle attack. In this attack a third party can disrupt the public key communication and then modify the public keys.
  • If user private key used for certificate creation higher in the PKI(Public Key Infrastructure) server hierarchy is compromised, or accidentally disclosed, then a “man-in-the-middle attack” is also possible, making any subordinate certificate wholly insecure. This is also the weakness of Public key Encryption.
  • Confidentiality can be achieved using Public Key Encryption. In this the Plain text is encrypted using receiver public key. This will ensures that no one other than receiver private key can decrypt the cipher text.
  • Digital signature is for senders authentication purpose. In this sender encrypt the plain text using his own private key. This step will make sure the authentication of the sender because receiver can decrypt the cipher text using senders pubic key only.
  • This algorithm can use in both Key-management and securely transmission of data.

Difference Between Symmetric and Asymmetric Encryption

  • Symmetric encryption uses a single key that needs to be shared among the people who need to receive the message while asymmetrical encryption uses a pair of public key and a private key to encrypt and decrypt messages when communicating.
  • Symmetric encryption is an old technique while asymmetric encryption is relatively new.
  • Asymmetric encryption was introduced to complement the inherent problem of the need to share the key in symmetrical encryption model, eliminating the need to share the key by using a pair of public-private keys.
  • Asymmetric encryption takes relatively more time than the symmetric encryption.




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Akshat Srivastava

An Avid Coder | Cybersecurity Enthusiast | Web developer | Geek | Technical Writer