Encryption / Hashing / Signing

1. Encryption:

Encryption is the process of converting readable data (plaintext) into a coded form (ciphertext) to prevent unauthorized access. Only authorized parties with the decryption key can convert the ciphertext back into readable data.

• Use Case in Cloud:

  • Data-at-rest encryption: Cloud providers encrypt stored data (e.g., files, databases) to protect sensitive information from unauthorized access.

  • Data-in-transit encryption: Ensures that data is encrypted while being transferred between users and cloud services (e.g., using HTTPS or TLS/SSL protocols).

  Example: Encrypting customer data in a cloud database to ensure that even if an attacker gains access to the storage, the data remains unreadable.

• Types of Encryption:

  • Symmetric encryption uses the same key for both encryption and decryption of data. The key must be kept secret, and it is faster than asymmetric encryption, making it ideal for encrypting large amounts of data. Common examples include AES and DES, and it is typically used for encrypting data at rest, such as files stored in cloud services.

  • Asymmetric encryption, on the other hand, uses a pair of keys: a public key for encryption and a private key for decryption. This method eliminates the need for secure key exchange, making it suitable for secure communications and digital signatures. Common examples are RSA and ECC, and it is widely used in scenarios like securing email communication, digital signatures, and key exchange protocols like SSL/TLS.

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2. Hashing:

Hashing is the process of converting data into a fixed-length string (hash) using a cryptographic algorithm. The output, called a hash value or digest, is unique for different inputs, and even a small change in the input data results in a significantly different hash. Hashing is a one-way process (irreversible).

• Use Case in Cloud:

  • Password storage: Cloud services store hashed passwords rather than plaintext ones to protect user credentials.

  • Data integrity: Hashes are used to verify that data hasn’t been altered during transmission (e.g., comparing the hash value of uploaded data against the original hash).

  Example: Storing hashed passwords in a cloud-based authentication system, ensuring that passwords are not exposed even if the database is compromised.

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3. Signing:

Signing refers to the process of applying a cryptographic signature to data to verify its authenticity and integrity. Digital signatures are created using a private key, and the signature can be verified by others using the corresponding public key. Signing ensures that the data has not been altered and comes from a verified source.

• Use Case in Cloud:

  • API authentication: Cloud services use digital signatures to authenticate API requests, ensuring that only authorized users or systems can access or modify resources.

  • Data integrity: Cloud-based applications use signing to ensure that uploaded files or data haven’t been tampered with during transmission.

  Example: A cloud storage service uses digital signatures to verify the integrity of files being uploaded by users, ensuring that they haven’t been altered during transmission.