Origin of the term

The name comes from the case/story “Sybil”, associated with multiple identities.

What is a Sybil attack

An attacker creates many fake nodes/accounts to gain disproportionate influence in distributed systems.

Common impact areas:

• P2P networks
• social platforms
• blockchain consensus and voting

Mitigations

• Proof of Work (resource-cost barrier)
• Proof of Stake / stake-based identity weight
• identity and reputation systems
• economic and protocol-level anti-spam controls