Do you know? An often overlooked threat faced by blockchain networks is called a Sybil attack. The name sounds a bit strange, actually originating from a literary work about a person with dissociative identity disorder, and later used to describe a specific threat in cybersecurity—where a single entity creates multiple fake identities to manipulate the entire system.

This type of attack is especially easy to occur in decentralized networks because all nodes are theoretically equal, and decisions are made through consensus. Due to this design, attackers can easily create multiple nodes to influence the consensus process. In 2016, Ethereum experienced such a situation, where attackers generated a large number of fake nodes, causing network congestion and transaction confirmation delays. Two years later, IOTA also faced a similar Sybil attack, even being forced to halt operations temporarily.

This also explains why this type of attack remains a persistent problem in the crypto space. While the decentralized nature of blockchain offers freedom, it also creates vulnerabilities. The attacker’s goal is simple—either to gain unfair advantage or to directly disrupt the normal operation of the network.

Interestingly, this concept is not new. As early as 2002, Microsoft researcher John Douceur first introduced the idea of a Sybil attack, initially targeting peer-to-peer networks. Since then, this attack method has appeared in file-sharing networks, online voting systems, and even social media.

The good news is that the industry has developed some defenses. Proof of Work (PoW) and Proof of Stake (PoS) consensus mechanisms make it costly for attackers to control the majority of nodes—costs are too high and not worth it. Another trend is that more projects are adopting identity verification and reputation systems, assigning trust scores to each node, making it difficult for attackers to create multiple trusted identities.

Overall, Sybil attacks pose a real threat to the security of peer-to-peer networks, especially in the cryptocurrency field. How to effectively defend against such attacks directly relates to the long-term stability and reliability of blockchain networks. Currently, most mainstream trading platforms have implemented strict security measures at the network layer to counter these threats, ensuring a sufficiently secure trading environment for users.