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2017-11-11

Asymmetric encryption – Explained.

Kriptografi

How does public-key cryptography work? What is a private key and a public key? Why is asymmetric encryption different from symmetric encryption?

Asymmetric encryption, also known as public-key cryptography, is a cryptographic system that uses a pair of related keys: public and private. The public key can encrypt data, but only the private key can decrypt it. This makes asymmetric encryption more secure than symmetric encryption, which uses the same key to encrypt and decrypt data.

Asymmetric encryption is used in a variety of applications, including:

  • Secure communication: Asymmetric encryption can encrypt messages so that only the intended recipient can read them. This is used in email, file transfer, and instant messaging applications.
  • Digital signatures: Asymmetric encryption can be used to create digital signatures, which are used to verify the authenticity of a message or document. This is used in applications such as electronic commerce and software distribution.
  • Key exchange: Asymmetric encryption can be used to exchange keys for symmetric encryption. This is used in applications such as TLS/SSL, which is used to secure web traffic.

Here is how asymmetric encryption works:

  1. The sender generates a pair of public and private keys. The public key is published, but the private key is kept secret.
  2. The sender encrypts the message with the recipient’s public key.
  3. The recipient decrypts the message with their private key.

Because the private key is kept secret, only the intended recipient can decrypt the message. This makes asymmetric encryption more secure than symmetric encryption.

Here are some of the advantages of asymmetric encryption:

  • It is more secure than symmetric encryption.
  • It can be used to encrypt and decrypt data over an insecure channel.
  • It can be used to create digital signatures.

Here are some of the disadvantages of asymmetric encryption:

  • It is more computationally expensive than symmetric encryption.
  • It requires exchanging public keys, which can be a security risk.

Overall, asymmetric encryption is a powerful tool that can be used to protect data. It is more secure than symmetric encryption but also more computationally expensive. The choice of which type of encryption to use depends on the specific application.