A Proof of Stake layer for Tendermint is built on top of Heimdall & Bor. When two-thirds of the validators sign a checkpoint, it becomes part of the root chain.
We enable PoS on our platform by using Ethereum staking management contracts and incentivized validators running Heimdall and Bor nodes. These implement the following features:
The ability for anyone to stake BONE tokens on the Ethereum smart contract and join the system as a Validator
Earn staking rewards for validating state transitions on Shibarium
The PoS mechanism also acts as a mitigation to the data unavailability problem for our sidechains in terms of Plasma.
The sidechain state is periodically finalized via checkpoints via our fast finality layer. Our fast finality helps us cement sidechain state. A chain compatible with EVM has fewer validators and a faster block time with high throughput. There is an emphasis on scalability over high levels of decentralization. Heimdall ensures that the final state commit is bulletproof and passes via a large validator set and hence high decentralization.
DApp developers can create a PoS security DApp simply by deploying their smart contract on Shibarium. Because the account-based architecture enables an EVM-compatible sidechain, this is possible.
Shibarium provides Plasma Guarantees for different atack scenarios.
Chain operator (or in Shibarium, the Heimdall layer) is corrupt.
The user is corrupt.
Shibarium offers a solution for users whose plasma chain assets have been compromised, as they can initiate a mass exit using rootchain smart contracts. The use of plasma contracts provides added security to Shibarium, as they rely on Ethereum's smart contracts and consensus mechanism. This means that the plasma chain can use simpler consensus mechanisms while still maintaining a high level of security comparable to the main chain. However, the overall security of Shibarium is still ultimately dependent on the security of Ethereum.
If you want to build DApps on Shibarium with Plasma security guarantee, you must write custom predicates for your smart contracts. Basically, this means writing the external contracts that handle the dispute conditions determined by Shibarium plasma.
The DApps on Shibarium can utilize either pure Plasma security or pure Proof of Stake security, or a hybrid approach that combines both. Developers can choose to implement a hybrid approach to provide both plasma and proof of stake guarantees in specific workflows. For instance, a gaming DApp that utilizes its own erc20 token to reward players can deploy game logic smart contracts directly on the Shibarium sidechain, ensuring Proof of Stake security. At the same time, Erc20 token transfers can be secured with Plasma guarantees and fraud proofs that are embedded in Shibarium's rootchain contracts.