Intro:
- Ethereum 2.0 is a set of interconnected upgrades to the Ethereum network that aims at making Ethereum more scalable, more secure and more sustainable. These changes are worked on by multiple different teams in the Ethereum ecosystem, each team focusing on building a specific part of the whole upgrade
- Scalability: 15 TX/s to 1000 TX/s
- Security: 51% Attack
- Sustainability: PoW to PoS
Transformation
- PoW: Miner,Electricity
- PoS: Validator, Economic Incentives
- Slashing: Validators lose part of their staked ETH if they decide to act dishonestly)
- Scalable: Sharding
- Sustainable: No miners
- Security: 51% Ataack
- Sharding(Solution to Scalability):
- Sharding is a database partitioning technique being considered by blockchain networks and being tested by Ethereum.
- The more users that blockchain networks take on, the slower the network becomes, leading to significant latency.
- Sharding can improve network latency by splitting a blockchain network into separate shards—each with its own data, separate from other shards.1
- The Beacon Chain(Phase 0)
- A massive new structure is being built alongside Ethereum. The core of this structure is the Beacon Chain, which reforms the consensus model from PoW to PoS.
- Randomly assign staked to validators to create a new PoS network that runs in parallel to the current Ethereum chain
- The Shard Chain(Phase 1)
- Current Ethereum chain becomes one of the shard in ETH2 PoS system.
- Data Sharding
- The Great Merge/ Docking(对接/入坞)(Phase 1.5)
- After the Ethereum 2.0 network establishes shard chains, the next major step will be to merge the current Ethereum mainnet to Ethereum 2.0. Lately, the term for this has been “docking”.
- Combination of Sharding and Rollups?(Phase 2.0)
Scaling Issues
- Concept of Scaling
- Layer1: Settlement/Base/Consensus Layer
- ETH2.0 use PoS & Sharding to greatly increase Transaction Throughput on Layer1
- Scalability Trilemma：Security, Scalability, Decentralization，讨论了理论上只做Layer1 Scaling 可能会导致中心化和安全等级降低
- Layer2: Computational Layer built on top of Layer1, Scale the network by offloading computational work to another Layer2, and留状态变量在Layer1
- Cause of Scaling — Congestion
- 2017: Bull Market for ICOs CryptoKitty clock up the entire Ethereum network, causing a major spike in the gas fees.
- 2020: the congestion came back even stronger, causing gas price to be as high as 500 GWEI. Therefore, we need Scaling to increase Transaction Throughput and Speed
- Two main Solutions to Scaling:
- Layer2 Scaling: rely on main layer security, up TX TP/Speed in L2 by handling TX Off-chain, Gas fee ↓
- Rollups: Provide scaling by executing transaction outside the Layer1 but posting data on Layer1
- Optimistic rollups: Optimism, EVM-Compatible VM(OVM), Arbitrary Contract Execution. Application-Specific,Plasma, Child chain Long waiting period, Side chains
- ZK rollups: Starkware, zkSync
- Matic Plasma Chains(offloading to child chain, long waiting periods)
- Side Chains: Allow users to send tokens from the main chain and receive them from the side chain. Once the fund is transferred, they can be used/withdrew. have a separate consensus mechanism, less secure
- Matic PoS Side Chain
- AAVE, Sushiswap
Rollups
- Three Solutions to Ethereum Scaling
- Layer1 Scaling
- ETH2: PoS, Sharding, PoW to PoS
- Layer2 Scaling
- Application Specific, such as Channels
- Rollups!! （Core L2 Solution）
- Allows for deploying all existing smart contracts present on Ethereum to a rollup with little or no changes while not sacrificing security
- Side Chains
- General Purpose
- A side chain is essentially just a blockchain that is linked to another main blockchain.
- Each of these chains has its own set of rules, functionalities, and purposes. Although they remain independent from one another, together they form an entire ecosystem.
- Rollups Steps: Executing TX outside of Layer1, Posting TX data on Layer1
- Takes the data
- Process the data
- Batch/Roll up data and post to main chain
- Optimistic Rollups — Fraud Proofs
- Post data to Layer1 and assume it correct
- Dispute resolution, bonded ETH slashed, 报错后在主链上再试跑一次，出错惩罚，这一流程花费时间较长
- Easier to design and apply
- Types: Optimism, Arbitrum
- ZK Rollups— Validity Proofs
- No Dispute resolution
- No long withdrawal time
- Zero-Knowledge Proofs 运用多次诘问-响应方式达到强化系统安全性的目的
- Downside: much harder to create EVM-Compatible, hard for general-purpose, Require high-spec machine
Polygon (Ethereum’s Internet of Blockchain)
- Matic Networks in 2017 to tackle ETH Scaling
- Polygon is a protocol and a framework for building and connecting Ethereum-compatible blockchain networks. Aggregating scalable solutions on Ethereum supporting a multi-chain Ethereum ecosystem.
- Support two major types of ETH-compatible networks
- Stand-alone Chain: rely on own security, has their own consensus model(PoS/delegated PoS)
- Secured Chains: utilize security as a service model (fraud proofs/validators) offers highest level of security and sacrifice independence, preferred by start-ups
- Polygon Architecture(Checked = mandatory):
Ethereum Layer: finality/staking/disputes/messaging
Security Layer:validator management/reward/shuffling
Polygon Network Layer: tx collation/consensus/block production
Execution Layer: Execution environment, execution logic
- Two main Solutions to Scaling:
- Layer2 Scaling: rely on main layer security
- Rollups: Provide scaling by executing transaction outside the Layer1 but posting data on Layer1
- Optimistic rollups: Optimism
- ZK rollups: Starkware, zkSync
- Matic Plasma Chains(offloading to child chain, long waiting periods)
- Side Chains: have a separate consensus mechanism, less secure
- Matic PoS Side Chain
- Polygon Commit Chain vs Side Chains
- Permissionless Validators