What does Avalanche Effect mean?
In the case of the SHA-256 encryption algorithm, it does not matter if your input is large or small, the output will always have a fixed length of 256 bits. This becomes critical when dealing with large volumes of data and transactions. So basically, instead of memorizing input data, which can be very large, you can memorize and track hashes.
An encryption hash function is a special class of hash functions that has different properties, making it ideal for encryption. There are certain features that an encryption hash function must have, to be considered secure.
Today I want to focus on just one feature known as the avalanche effect.
What does Avalanche Effect mean?
Even if you make a small change in your input, many changes will be reflected in the hash. Check how much it has affected the output hash. Now let’s go back to the previous part of the article (blockchain architecture). One thing we said was: The blockchain is a linked list that contains data and a hash pointer that points to its previous block. What is a hash pointer? A hash pointer is similar to a pointer, but instead of just having the address of the previous block, it contains the hash data inside the previous block. This small change makes the blockchains amazingly reliable and secure.
Imagine this for a moment, a hacker attacks Block 3 and tries to change the data. Due to the properties of hash functions, a slight change in the data drastically changes the hash. This means that any minor change in block 3 will change the hash stored in block 2, now that the data and block 3 hash has changed, it will lead to a change in block 1, etc. So it is a matter of completely changing a chain. it’s impossible. This is exactly how blockchain achieves immutability.