RIPEMD 160: What Is It, How It Work, Applications & Benefits

A key component of blockchain technology and digital security, especially in Bitcoin, is the cryptographic hash function RIPEMD 160.

What is RIPEMD 160 and its Origin?

The RACE Integrity Primitives Evaluation Message Digest 160-bit version is known as RIPEMD-160.
With an input of arbitrary size, this cryptographic hash function generates a fixed-size output of 160 bits (20 bytes), which is typically expressed as a 40-digit hexadecimal number. It was created as part of the RIPE project in the mid-1990s (more precisely, 1996) by the Belgian COSIC research team, which included Hans Dobbertin, Antoon Bosselaers, and Bart Preneel.
It was created to solve the security flaws of previous algorithms such as MD4, MD5, and the original RIPEMD and to be a better and more secure version of those algorithms. Additionally, it provided a safe and open substitute for hash functions such as SHA-1, particularly in the context of discussions concerning confidence in U.S.-designed encryption.

Similar to other cryptographic hash functions, RIPEMD-160 demonstrates a number of important characteristics:

Deterministic: The hash output will always be the same given the same input.
One-way (Pre-image Resistance): Reversing the process and obtaining the original input from its hash value is not possible from a computational standpoint. As a result, the original input cannot be recovered from the output.
Collision-resistant: Finding two distinct inputs that result in the same hash output is quite challenging. Although theoretically feasible because of the hash’s finite size, RIPEMD-160 is engineered to make it very challenging to identify such collisions.
Avalanche Effect: The output hash is significantly altered by a little change in the input.

The Merkle-Damgård construction with a distinctive “double-branch” structure is the basis of the RIPEMD-160’s basic design.In order to make sure the input data (message) is a multiple of 512 bits, it is first padded.
Double-Branch Processing: Next, 512-bit blocks of the padded data are processed. RIPEMD-160 employs two separate and parallel lines of operation, in contrast to many other hash algorithms.
Five rounds of intricate mathematical transformations are present in each of these lines. 32-bit words from the message block and a constant serve as the inputs for these stages. Each block concludes with interaction between the two branches.
Non-Linear Functions: In order to produce the avalanche effect, the algorithm makes use of non-linear functions, which are bitwise operations (such as XOR, AND, and OR) and adds.
Compression Function: This function ensures that the output combines the input message and the hash’s current state by complexly mixing inputs.
Hash Generation: The algorithm’s resilience to specific kinds of assaults is improved by this dual-stream approach, which uses distinct sets of constants and operations. The final 160-bit hash value is created by combining the outputs of the two lines after processing every block.

Even if SHA-256 is more well-known, RIPEMD-160 is still important in cryptography. Among its uses are:

The Bitcoin protocol is one of the most well-known use of blockchain technology. Bitcoin creates a public address from a public key via a procedure known as Hash160. A two-step hashing procedure is used here:
- The SHA-256 algorithm is used to first hash the public key, yielding a 256-bit hash.
- The RIPEMD-160 technique is then used to reduce the SHA-256 hash result to a 160-bit value. HASH160 = RIPEMD-160(SHA-256(public key)) is one way to express this. For Bitcoin addresses, this two-step procedure has the following advantages:Shorter/Compact Addresses:
- Users can handle and utilize Bitcoin addresses more effectively because a 160-bit hash is shorter and more compact than a 256-bit hash.
Layered Security: A strong and multi-layered defence against potential weaknesses is offered by combining two distinct, well recognised hash algorithms.
secrecy: A layer of secrecy is added for funds that are not yet in motion by keeping the public key secret until money is spent from the address.
Resistance to Quantum computer Attacks: By making reverse-engineering more difficult, the dual-hash technique is thought to provide some protection against upcoming quantum computer attacks.
Digital signatures: guaranteeing the integrity and genuineness of electronic documents.
Verifying the integrity of files is known as file verification.
Password Hashing/Storage: To improve security, store password hashes rather than plain text passwords.

No matter the size of the input, the fixed-length output always generates a 160-bit hash, offering a standardised format for integrity checks.
Finding two distinct inputs that provide the same output hash is computationally impossible because to high collision resistance.
Efficient Computation: In contexts with limited resources, RIPEMD-160’s computational efficiency is a benefit, even with its intricate internal mechanisms.
Openly Designed and Well-Analyzed: It was publicly accessible and unpatented, and its open design contributed to its rise in popularity.
Considered Secure: Still seen as safe from real-world threats.

Feature	RIPEMD-160
Output size	160 bits (20 bytes)
Developed by	COSIC Group (1996)
Design goal	More secure and longer than RIPEMD
Type	Cryptographic hash function
Use in Bitcoin	To create addresses (HASH160)
Current status	Still secure but less common than SHA-2/SHA-3

Slower than Modern algorithms: SHA-2 and other more recent hash algorithms may be faster than it.
Less Commonly utilized Today: SHA-256 and SHA-3 are now more extensively utilized methods that are not limited to blockchain or outdated systems.
No hash function is completely future-proof because what is secure now might not be tomorrow due to developments in computing power and cryptography research, which calls for constant improvements in cryptographic security.
Theoretical Collisions: Because of the finite output size, it is theoretically possible for distinct inputs to yield the same hash, even if this is extremely unlikely and computationally impractical (a collision).

When compared to previous functions like MD5 and SHA-1, which both have known weaknesses, RIPEMD-160 provides a better mix between speed and security.
However, because of its greater 256-bit digest size, SHA-256 which is frequently employed in the Bitcoin blockchain with RIPEMD-160 generally offers a higher level of security, albeit at the expense of more processing power.
Enhancing security and efficiency are the main goals of modern research in cryptographic hash functions, and although if RIPEMD-160 may not be as well-known in these studies, it nevertheless gains from general developments in the field.