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Hashing, salting and cryptographic algorithms are key techniques used together to protect sensitive data and communications by enabling confidentiality and integrity.
With data breaches and cyber attacks on the rise, applying robust security measures has become crucial. Hashing, salting and using secure algorithms are key techniques used by security professionals to safeguard sensitive data and systems. This blog provides an overview of these concepts and their significance in data security.
Understanding Hashing
Hashing refers to the process of converting any input data into a fixed size value using a one-way cryptographic function called a hash algorithm or hash function.
Some examples of popular hash functions include:
- MD5 - Produces a 128-bit hash value
- SHA256 - Generates a 256-bit hash output
- BLAKE2 - Creates hashes of up to 512 bits
The key properties of hashing are:
- Hashing is a one-way process. The original data cannot be retrieved from the hash.
- Even a small change in the input drastically changes the hash value.
- The same input always generates the same hash output.
Hashing enables verifying integrity of data by comparing hashes. It is extensively used for password storage, message authentication, blockchain ledgers etc. The one-way nature of hashing makes it suitable for securely storing sensitive data like passwords.
The Role of Salting
In cryptography, salting refers to the addition of random data called salt to the input before hashing. Salting enhances security by making dictionary attacks against hashed passwords difficult.
Some guidelines for salting:
- Use a cryptographically secure random number generator for creating salts.
- Generate a new, unique salt value for each input.
- Store salts securely, not just appended to hashed data.
For example, to hash the password “pass123” with SHA256 and a salt, the input to the algorithm will be “pass123kdi39dkd93”. The salt “kdi39dkd93” gets stored along with the hash output.
Salting significantly improves the strength of hashing for password storage. It prevents use of precomputed rainbow tables to breach hashed passwords.
Overview of Algorithms
In computer science, an algorithm refers to a sequence of instructions or logic designed to perform a specific task. Cryptographic algorithms are essential for security applications like encryption, authentication, securing communications etc.
Some common classes of cryptographic algorithms include:
- Symmetric key algorithms (AES, DES, RC4)
- Asymmetric key algorithms (RSA, ECC, Diffie-Hellman)
- Hash algorithms (MD5, SHA2, SHA3)
- Key derivation functions (PBKDF2, Argon2, Scrypt)
Properly implemented cryptography provides the foundation for data confidentiality and integrity. Using secure, standardized algorithms validated by experts is critical for robust security.
Hashing vs Encryption
Though related in the context of security, hashing and encryption have different use cases:
- Encryption is two-way, data can be decrypted with the key. Hashing is one-way.
- Encryption provides data confidentiality. Hashing is used for integrity verification.
- Hash outputs are irreversible. But encryption is reversible with the right keys.
Hashing alone cannot prevent data from being read or modified by an adversary. Encryption provides confidentiality by transforming data into a form unreadable without keys.
Using hashing and encryption together as a multi-layered security approach is more robust. For example, encrypt data for transmission and additionally hash it to verify integrity on receipt.
Conclusion
Applying concepts like hashing, salting and using vetted algorithms provides strong security foundations for applications dealing with sensitive data, communications and transactions. Though opensource tools exist, expertise is needed to configured them correctly. Hashing protects stored data while encryption secures data in transit or use. Together, they enable building robust systems resilient to common attacks and unauthorized access.
