One-Way Hash Function: Dynamic Algorithms

Put simply, a hash function scrambles data to encrypt it, making it unreadable without special keys or difficult hacking techniques.

While there are many types of two-way encryption, hash functions are one-way encryption, which makes them even tougher codes to crack. Using math, one-way hash functions keep your data safe.

One-way hash functions are also called hash functions, hash encryption, hashing algorithms, and message digest functions. This type of encryption is extremely secure, as it is almost impossible to determine the hash value unless the hacker knows which hash algorithm was used.

With standard forms of encryption, a hacker can steal the full set of encrypted passwords that might contain the key. With one-way hash encryption, finding the key becomes more difficult.

How it works

A one-way hash function starts with a group of characters, called a key, which you then map onto a hash, or hash value, which is a certain length.

Modern hashes are 128 bits or more; however, the hash value will be shorter than the original string of characters.

The hash value is sometimes called a message digest. This message digest is always unique once you scramble it. Without knowing the algorithm, there is no way to reverse the encryption process to find the password.

Before computers became our main way of applying mathematical algorithms, hash functions took a set of inputs of any size (for example, a long sentence like “Hello World” or “the quick brown fox jumped over the lazy dog”) and used mathematical encryption to fit this data into a table or similar data structure that contained fixed- sized elements. The hash refers to a value in the hash table or the data structure.

Since computers now apply one-way hash functions to encrypt information, the process looks more like this: 

• A user enters a password and ID into their browser.
• They send this information through a secure link.
• An authentication server receives the information.
• The server uses the ID to find the user’s message digest, like hashes were originally used for databases.
• The password is hashed using the same algorithm.
• When the hashed password matches the one in the server, the user is authenticated and can retrieve their data.

Common uses

One-way hash functions were originally used in databases since it is easier to find a short string of information in a hash than to find a full, long string of characters. Since their development, one-way hash functions have been used more often in encryption.

People can use hashing to encrypt and decrypt digital signatures. The digital signature is transformed into a hash value and sent to the receiver. Once the receiver has the encrypted value, the computer uses the same hash function to generate the hash value. It then compares this with the message. If the two are the same, the message was sent with no errors.

The most familiar application of one-way hashing is through cryptocurrencies like Bitcoin. If you want to trade in this incredibly valuable market, it helps to know something about one-way hash encryption.

Hash algorithms

Two types of one-way hash algorithms include: 

• Folding. This process takes the original one-way hash value, divides it into many separate parts, adds those values together, and uses the last four digits as the key.
   
• Digit rearrangement. This form of hash encryption rearranges the order of most digits in certain places (for example, the second digit replaces the seventh) and then reverses the order. The remaining number, which has not been rearranged, is the key. 

References

Hash Function. (March 2018). Techopedia.

Hashing Functions and Their Use in Cryptography. University of Missouri, St. Louis.

Why Salted Hash is as Good for Passwords as for Breakfast. (December 2013). GCN.