<p>Definite yes.</p>
<p>The Sybil attack in computer security is an attack wherein a reputation system is subverted by forging identities in peer-to-peer networks.</p>
<p>If nodes are required to prove their identity before they can join the network, just like in permissioned or private blockchains, they will not be able to forge the identities.</p>

CC BY-SA 4.0
2018-01-23T18:50:57.217Z
2022-08-16T14:21:00.370Z
2022-08-16T14:21:00.370Z
Preet
<p>it appears that although not totally water-proof to Sybil attacks, Bitcoin network seems quite resilient to these kind of attack <a href="https://bitcoin.stackexchange.com/questions/57150/preventing-sybil-attacks-how-does-bitcoin-get-to-know-the-computing-power-of-a/57153#">Preventing Sybil attacks</a>. Is it true to assert that permissioned or private blockchain are less exposed since there is a certain level control of the participant allowed to enter the network ?  </p>

<blockchain><attack><sybil-attack>
resilience to sybil attack - public vs private
user2478159
# resilience to sybil attack - public vs private

(Asked by: username_0 on 2018-01-23)

it appears that although not totally water-proof to Sybil attacks, Bitcoin network seems quite resilient to these kind of attack [Preventing Sybil attacks](https://bitcoin.stackexchange.com/questions/57150/preventing-sybil-attacks-how-does-bitcoin-get-to-know-the-computing-power-of-a/57153#). Is it true to assert that permissioned or private blockchain are less exposed since there is a certain level control of the participant allowed to enter the network ?

**Tags:** blockchain, attack, sybil-attack


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## 1 answers

### Answer by username_1 on 2018-01-23. Score: 1

Definite yes.

The Sybil attack in computer security is an attack wherein a reputation system is subverted by forging identities in peer-to-peer networks.

If nodes are required to prove their identity before they can join the network, just like in permissioned or private blockchains, they will not be able to forge the identities.


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