Do you know what “double spending” means when it comes to crypto? Have you pondered how it works and the means of protection against it? If you want to know more, this guide is all you need to read.
What is Double Spending?
The term “double spending” refers to the practice of using the same kind of virtual money for more than one transaction. This challenge is peculiar to digital currencies since, in comparison to conventional cash, it is far simpler to replicate digital currency.
Problems may emerge if there are a large number of simultaneous transactions that utilize the same input of digital money. Because of this vulnerability in digital money, the value of the currency system as well as people’s faith in it might potentially decrease.
How Does It Work?
A distributed ledger known as a blockchain is used to keep track of all transactions involving a particular digital currency. A hash is an encrypted integer that is created whenever a new block is added to the blockchain. This hash comprises data from the previous block, as well as transaction details and a timestamp.
In order to encrypt the hash, a cryptographic technique similar to the SHA-256 algorithm is used. Miners are required to validate each new block using a consensus technique, such as proof-of-work, before it can be added to the public blockchain.
However, in order to double spend, a person would have to create a parallel blockchain that could keep up with the public one. They would then need to present this hidden chain to the network until it catches up, at which point it will be accepted as the most recent block and added to the chain.
Once the hidden chain is included on the blockchain, an attacker may double-spend the original digital currency. This can result in a loss of funds and a decrease in confidence in the cryptocurrency market.
Types of Double Spending Attacks
There are numerous different varieties of double-spending attacks, each with its own unique complexity and potential effect. The following are some frequent instances of assaults that involve double spending:
51% Attack
A 51% attack occurs when an adversary gets control of more than 51% of the resources available on a network. Attackers that have greater mining skills may take control of the blockchain and initiate assaults that include double-spending.
Finney Method
An attack using the Finney method takes advantage of a race condition that exists between two independent transactions. The attacker starts a transaction to deliver digital currencies to a vendor but simultaneously starts a second, disguised transaction to return the same electronic money to the attacker.
Vector76 Attack
An attacker will construct a transaction and then broadcast it across the network in order to carry out a Vector76 attack. The attacker will then produce a distinct and untraceable chain of blocks that will include the transaction that is being challenged.
In the event that the length of the hidden chain is found to be greater than the length of the preliminary chain, the competing transaction will be regarded as accepted rather than rejected.
How To Prevent Double Spending Attacks?
A blockchain may be protected against potential double-spending attacks by implementing a number of different protections.
A trustworthy method of reaching an agreement is essential to the protection of the network. By guaranteeing that previous values cannot be regenerated, “replay” attacks may be successfully thwarted. The usage of timestamps is another method that may be used to show the block’s integrity and prevent the occurrence of duplicate spending.
There is also a possibility of having centralized supervision that makes sure no double spending-related attacks happen as they constantly authorize and look over all the transactions that are happening. However, this model may not adhere to the fundamental principles of blockchain technology.
