Casper Protocol


Casper Protocol is inspired from “Casper – The Friendly Ghost” a cult classic movie. The Ethereum developing team even started calling it “The friendly ghost” because of the incentives that are designed to guarantee censorship resistance against the incentives that force the cartel to be friendly to the non-cartel validators. This is a hot topic and one of the popular topics in the Ethereum web forums lately.

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Casper is the next-gen PoS protocol that Ethereum has chosen to go with. Vlad Zamfir, Ethereum’s lead researcher on proof of stake is the face of Casper.

What makes Casper different from other Proof of Stake protocols?

Casper implemented a process through which they can punish all malicious elements.

Working of PoS under Casper:

  • The validators can now stake a portion of their Ethers at stake.
  • What follows next is that they will start validating the blocks. When the validators discover a block which they think can be added to the chain then they will validate the block by placing a bet on it.
  • And if the block gets attached then the validators will be rewarded for their proportioned bets.
  • But if a validator starts acting in a malicious manner and won’t do anything as in tries to do a “nothing at stake”, then the validator will immediately be rebuked and all of their stakes will get slashed without any fair warning.

So, Casper is specially designed to work in a trustless system and it will be more Byzantine Fault Tolerant. If someone acts in a Byzantine manner meaning in a malicious way then they will be punished immediately by having their stake slashed off. This is how Casper is different from most other PoS protocols.

This is not the only way where Casper punishes the validators. Casper is designed to guarantee network security, Casper will also punish the miners who go offline even if it’s unintentional.

Moreover, Casper is not a specific project. It is a combination of two research projects that is currently undertaken by the Ethereum Development team. The projects are:

  1. Casper the Friendly Finality Gadget (FFG)
  2. Casper the Friendly GHOST: Correct-by-Construction(CBC)

Casper FFG:
Casper FFG aka Vitalik’s Casper is hybrid PoW/PoS consensus mechanism. This version of Casper will be implemented first and it is designed in a way to ease the transition into PoS. There is a PoS protocol that overlays on the top of the normal ethash PoW protocol. With this version, the blocks will be mined via PoW, and in every 50th block, there will be a PoS checkpoint where finality is assessed by a network of validators.

Casper CBC:

Casper CBC aka Vlad’s Casper uses the correct-by-construction (CBC) protocol. CBC is going to be heavily influenced by both Vlad’s and Vitalik’s Casper meaning it is going to be the best of both worlds. Many details will be revealed once it will be set for a release.

The advantages of implementing proof-of-stake are:

  • Energy efficiency.
  • Economic security.
  • Scaling.
  • Transition to POS.
  • And most important part of them all, Achieving Decentralisation.
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