All terms
Stopping one person from pretending to be thousands.
A Sybil attack is one actor creating many identities to gain disproportionate influence: farming an airdrop with a thousand wallets, swinging a governance vote, or gaming a reputation system.
Because creating a wallet is free and instant, every open system needs some answer to this. Options include proof of personhood, staking capital, reputation history and social graph analysis. None is perfect and all involve a privacy tradeoff.
Airdrop teams now spend significant effort filtering Sybil farmers, and the filtering regularly catches genuine users too.
That wallet counts measure people. One person can run thousands of wallets cheaply, which is exactly what airdrop farming is, and most user numbers you see have not been filtered for it. Unique wallets and unique humans are very different figures.
Common questions
Why does it matter if one person has many wallets?
How do protocols detect sybils?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More web3 terms
Want this explained out loud?
Some of these land faster in conversation than in writing. Sessions are one to one and you can ask anything, including the things that feel too obvious to ask.