Understanding the double hash in Ethereum
Calculation of Ethereum’s control amount is a critical element of cryptographic mechanisms. In this article, we are immersed in why the double subtraction is needed and what it achieves.
What is sha256?
The SHA-256 (Safe Hash Algorithm 256) is a cryptographic hash function, which is a fixed size, has a hash value from the input data. It is widely used for the integrity of the data and the verification of authenticity. Think like a digital fingerprint: each input has a unique output, and if the same input is cleared again, it will get the same result.
How does Ethereum control amount work?
Calculation of Ethereum’s check amount contains two Sha-256 hash:
1.
2.
The two hash obtained are connected and can be used to calculate the check amount.
Why do we need double hash?
Now let’s talk about why you use Ethereum double hash:
- Data integrity
: Double subtraction ensures that the same input creates a different output (or hash value). This is essential in cryptographic applications, where the integrity of the data is extremely important.
- Prevention of collisions
: The collision occurs when two different inputs result in the same output extract value. Double subtraction helps prevent this by force algorithm to generate a new hash from an already hashed input.
Why do we need two Sha-256 hash?
The second SHA-256 hash (connected to the original data) serves as an additional layer of security. The magic happens here:
- The first sha-256 hash uses the prefix that has been changed (ie attached to the original data).
- By combining both hash, Ethereum ensures that the collision between the two different inputs results in a different output value.
- When a collision occurs, the resulting hash values differ significantly, which makes this weakness extremely difficult for the attacker.
Conclusion
Double hash in Ethereum is not just a redundant operation; This is a critical element of cryptographic mechanisms. Using two Sha-256 hash, Ethereum ensures the integrity of the data and prevents collisions, thus providing a safer platform. This double withdrawal process allows you to use the RIPEMD160 (non -cryptographic hash function) as an additional safety layer of each application.
In the context of your original question:
When using the RIPEMD160, we need double subtraction to prevent collisions between different input values. By connecting both hash, Ethereum ensures that the collision results in a significantly different output value, which makes it difficult for attackers to use this weakness.