Plaintext to ciphertext and confidentiality goal

Summary

Encryption is the process of transforming plaintext (readable information) into ciphertext (an encoded form) so that, ideally, only authorized parties can decode it. While encryption does not stop interference by an attacker, it denies the attacker intelligible content, making decryption infeasible without the proper key and sufficient computational resources. In cryptography, confidentiality is achieved through the use of encryption keys and well-designed encryption schemes. Keys are typically either symmetric (the same key is used for encryption and decryption) or public-key (the encryption key can be public, while only the recipient has the matching decryption key). Encryption is widely used to protect data both in transit (e.g., over networks like the Internet) and at rest (e.g., stored on devices such as laptops or USB drives), supporting confidentiality against eavesdropping and unauthorized access.

Key Points

• 1

  Encryption converts plaintext into ciphertext to protect confidentiality by making unauthorized decoding computationally difficult.

• 2

  Confidentiality relies on encryption keys and appropriate scheme design; authorized recipients can decrypt with the correct key, while attackers cannot.

• 3

  Encryption is used to protect data in transit and at rest, helping mitigate risks from interception and theft.

• 4

  Symmetric-key and public-key encryption are the two main key paradigms used to achieve confidentiality.