🌫️ Nothing at stake

Ref: pos-faq, poel-alts

🌫️ Nothing at stake

Ref: pos-wiki, poel-alts

🧥 Bribery attacks

        Wins:    A     B
        vote A:  $100  $0

        vote B:  $102  $2

Ref: zack-pos, casper-bribery

• There are 100 voters with equal stake.
• If A wins, then every voter is $100 richer.
• I bribe all the voters $2 to vote for B.

• $200 is enough to destroy $10.000.

🧥 Bribery attacks

A secret vote, where you could prove your vote if you want to.

Challenge: You'll take the bribe only if you vote to destroy the blockchain!

        Wins:            Accept bribe  Reject bribe
        Destroyed:       0             0

        Not destroyed:   Stake+bribe   Stake

🧥 Bribery attacks

Estimated Value =
  (value if the attack fails) x (likelihood of attack failure)

(Bribe for one user) =

Estimated Value(no bribe) - Estimated Value(bribe) = 

  (value if the attack fails) x

  (how much more likely if the attack succeed, if they take the bribe)

(Bribe for one user) =
  (their stake) x (portion of stake that they control)

A secret vote, where you could prove your vote if you want to.

Challenge: You'll take the bribe only if you vote to destroy the blockchain!

🧥 Bribery attacks

(Bribe for one user) =
    (their stake)
    x
    (portion of stake that they control)

(Bribe for 1/2 of the total stake) =
    (1/2 of the total stake)
    x
    (average portion of stake)

Example:

(Bribe for 1/2 of the total stake) =
    (1/2 of the total stake)
    x
    (1/1000) = 

    (1/2000 of the total stake)

⛔ Censorship

Ref: fraud-proofs, pos-faq

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⛔ Censorship

Ref: fraud-proofs, pos-faq

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