Computer programmers have been using hashing functions for decades. These functions are typically used in the areas of security, data access, or data validation. A hashing algorithm is a mathematical function that converts a variable-length string of characters into a fixed numerical value. There are multiple types of algorithms available today. Each type is designed for a specific purpose.
A hash function is a mathematical function that creates a hash value from a set of character strings. When creating a hash function, it is important to safeguard against hash collisions. Unfortunately a hashing algorithm may create the same hash value with a different set of character data. This will cause a collision because two sets of data will have the same hash key.
Data encryption is one of the primary safeguards against intruders and malicious activities. The science of data encryption is known as cryptography. A hashing algorithm is the computer function that converts standard data into an encrypted format. There are many security types of hashing algorithms available today. Each function has a different complexity level for purposes of security.
The technique of hashing was first created as a method of improving performance in computer systems. A hash value is a numerical representation of characters of data. Numerical data has faster processing characteristics when searching through files of data. Many commercial databases use hash files as a method of indexing data within the database management system (DBMS).
The process of hashing has also been used as a method of protecting sensitive computer data. Hashed data requires an encryption program to convert the hash data back into a format that can be understood by human interpretation. It is nearly impossible decipher an encrypted data file without the original hashing algorithm.
An advanced hashing algorithm requires special keys that are used for the ciphering and deciphering of data. These keys are the secret ingredient for making encryption complex. The encryption key can range form 64 bits to 256 bits. As the size of the bits increases, the complexity of the hashing algorithm becomes more difficult to break.
Cryptography and hashing algorithms are managed by the National Institute of Standards and Technology (NIST). This group manages the standards for encryption functions for use in the United States government. Currently the defined standard is the advanced encryption standard (AES), which requires a 256-bit key.