List and define the different types of hashes and message digests.

A message digest function can also be referred to as cryptographic hash function Message digest is the representation of text in the form of a single string of digits which is created using the formula known as one way hash function. When you encrypt the message with a private key, you create a digital signature which becomes an electronic means of authentication. Hash functions can be defined as a vital part of message authentication codes as well as digital signature schemes. They deserve special attention and are used in cryptographic applications such as password storage, integrity checks, and analytical derivations. Every digest function, or algorithms, the computer has a different size differ in characteristics which may affect their security. There are different message digests known and used today. They include the Hashed Message Authentication Code (HMAC), Message Digest 2 (MD2), and Secure Hash Algorithm (SHA).

Hashed Message Authentication Code (HMAC)

This is a message authentication code which uses a cryptographic key together with a hash function. The server and the client are provided with a private key by the Hash-based message authentication code which only the specific server and the client are aware of. After that, the client forms a unique hash as per the server’s request by hashing the request data using the private key and later sends it as a part of the appeal. Hashing the core and the message in separate steps makes HMAC more secure than Message Authentication Code (MAC).

Message Digest 2 (MD2)

MD2 was developed by Professor Ronald L. Rivest of MIT and is an 8-bit and earlier version of MD5. It’s an algorithm which is used to verify data integrity. This is done by creating a 128-bit message digest from data input. The input, which can be a message of any length is termed as unique to the specific data as the fingerprint is per the particular individual. It is used with digital signature applications. MD2 requires that large files be compressed by a secure method. They are then encrypted using a secret key which is under public key cryptosystem. MD2 is Byte-oriented and produces a 128-bit hash value from an arbitrary-length message. It was designed for smart cards.

Secure Hash Algorithm (SHA).

SHA was modeled after MD4 and proposed by NIST for the Secure Hash Standard (SHS). This is a set of algorithms which was developed by the National Institutes of Standards and Technology (NIST) in conjunction with other governments and private parties. They have secure encryption functions which have risen to counter some top cybersecurity challenges of the 21^st century. Public service groups have partnered with various federal service agencies to provide the best security standards for different organizations as well as the public. SHA produces a 160-bit hash value. SHA has had multiple upgrades since it was formed in 1993. Both SHA 1 and SHA 0 features 16-bit hashing. SHA-2 has a set of two functions which have 256-bit and 512-bit technologies. SHA-3 also known as Keccak is a top-level secure hash algorithm. SHA I a part of new encryption standards which tries to prevent different types of attacks and keep sensitive data safe.