Invasion is a term used to describe an attack on cryptocurrency networks by malicious actors. Invasions can take various forms, including double spending, 51% attacks, and Distributed Denial of Service (DDoS) attacks.
Double Spending: Double spending is a type of invasion in which the attackers send multiple payments using the same coins or tokens in order to defraud merchants or other users. This attack works because digital currencies are not physical objects that have to physically move from one person to another; instead they are simply entries in public ledgers called blockchains. The attacker spends the same coin twice before it can be verified and accepted by the recipient.
51% Attack: A 51% attack occurs when an individual or group gains control over more than half of a blockchain network’s hashrate—the computing power used for calculations and transactions on a blockchain—and uses their majority control to manipulate transactions and rewrite history on the chain’s ledger. With this kind of power, attackers may be able to reverse transactions and create new ones without authorization from anyone else on the network.
Distributed Denial Of Service (DDoS) Attack: DDoS attacks involve flooding a target system with traffic until it becomes overwhelmed and unable to respond properly, preventing legitimate requests from being processed correctly. In terms of cryptocurrency networks, these types of attacks could lead to delayed confirmations or disruptions in service if enough malicious traffic is sent at once due to limited resources available within certain nodes that compose such networks. Typically these kinds of invasions originate from botnets consisting out hundreds or thousands computers under centralized control
