What is Starknet?
Starknet, a pivotal solution addressing scalability issues within blockchains like Ethereum, tackles the challenge of reduced speed and increased costs as user and transaction numbers surge. It aims to amplify the speed and cost-effectiveness of Ethereum transactions.
Developed by StarkWare Industries, an Israeli blockchain company, Starknet operates as a validity rollup or zk-rollup on the Ethereum network. These rollups execute the bulk of transaction operations off the Ethereum chain and then offer proof of these transactions to Ethereum. This approach lessens the burden on the Layer 1 blockchain, resulting in quicker and more economical transactions.
Starknet, established by StarkWare Industries in 2018, introduced itself as a permissionless Layer 2 network in February 2022. This infrastructure permits anyone to construct decentralized applications (dapps) on it. StarkWare also manages StarkEx, a platform operating since June 2020, but tailored for specific dapp necessities on a permissioned network.
Supported by renowned investors like Sequoia Capital, Paradigm, and Coatue, StarkWare attained a valuation of $8 billion during its Series D funding round in May 2022, raising a total of $261 million in funding.
Functioning as a Layer 2 solution, Starknet processes transactions within its network and then settles them on Ethereum to enhance scalability. This involves compressing numerous transactions into a "proof" data structure, submitted to Ethereum as a transaction. As a result, throughput significantly improves, increasing the number of transactions processed per second and lowering transaction costs.
Starknet relies on zk-STARK, a proprietary proof system ensuring transaction correctness without revealing sensitive data, thereby enhancing privacy and security.
Its fundamental components include Sequencers, responsible for executing transactions and suggesting blocks at a substantially higher transaction rate than Ethereum nodes, and Provers, offering a mathematical assurance of block transaction validity, eventually settled on Ethereum.
Starknet anticipates the introduction of its native token, STRK, anticipated to launch in April 2024, with deployment on Ethereum occurring in November 2022. With a total supply of ten billion, STRK will be utilized for transaction fees, governance, and staking within the Starknet network.
What is Cairo?
Cairo is a programming language tailored for a virtual CPU designed for cryptographic operations. It efficiently proves program execution, enabling complex operations on untrusted machines, checked swiftly on more affordable ones. Initially compiling to Sierra, an intermediate representation, Cairo 1 ensures a safe subset of CASM, enhancing provability even if computations fail.
It finds usage in Starknet, a solution for Ethereum scalability. Starknet, a Layer 2 solution atop Ethereum, utilizes a single node (the prover) to execute and prove user interactions, reducing computational demands compared to direct execution. This method boosts throughput, lowers transaction costs, and upholds Ethereum's security.
Differing from traditional languages, Cairo's execution involves two aspects:
Execution by the prover resembles typical language operation. While virtualized and potentially less efficient, optimization here isn't the critical concern.
Verifying the generated proof differs. It requires cost-effective verification since it could happen on numerous smaller machines. Cairo employs non-determinism to enhance this process. For instance, sorting an array in Cairo costs the same as copying it, as the verifier checks sorted order rather than performing the sort, making it cheaper.
Cairo's memory model emphasizes immutability. Once written, values in memory remain unchanged. Cairo 1 offers abstractions to manage these constraints, but developers need to strategize memory and data structure management for optimal performance, as full mutability simulation is absent.
What is ZKSync?
zkSync is a Layer 2 security solution utilizing zero-knowledge proofs for data protection. It offers a secure platform empowering developers to build fraud-resistant and censorship-proof applications.
This project facilitates secure transactions without reliance on third parties, ensuring trustless interactions. zkSync's advanced technology not only enhances Ethereum's throughput but also upholds Ethereum's core values, including freedom, self-sovereignty, and decentralization.
It stands for principles like:
Security: The core team ensures safety, reliability, and swift response to critical issues within zkSync's sequencer and protocol updates.
Community-owned: The long-term goal is complete decentralization, where the network's sequencer and governance become community-owned, securing zkSync's principles collectively.
Resilience: Beyond decentralization, zkSync aims for autonomy, inclusivity, and trustlessness for every network user, defining true resilience.
Forkability: zkSync maintains an open-source and forkable code, allowing termination of the protocol at any time, ensuring community control over governance and direction.
Trustlessness: zkSync integrates advanced zero-knowledge proof cryptography, aiming to eliminate trust assumptions from public blockchains, emphasizing verification through mathematics and code.
Technology and EVM Compatibility conclusion
The dissimilarity in zkSync and StarkNet's EVM compatibility arises from their use of distinct proofing techniques. To achieve 99% EVM compatibility in zkSync V2, Solidity and Vyper need initial compilation to Yul (an intermediate language), followed by reduction to zkEVM bytecode via LLVM. Notably, zkSync also supports Zinc, a ZKP optimized Rust-like language that directly compiles to bytecode through LLVM. However, Zinc's progress has halted since September 2021 due to zkSync's emphasis on Solidity compatibility, despite its ongoing need for Turing completeness.
On the other hand, StarkNet presently doesn't prioritize EVM compatibility. It necessitates developers' familiarity with Cairo, StarkWare's programming language for STARK provable programs, to establish smart contracts on its platform. Alternatively, developers can leverage Warp, a transpiler by NetherindEth, to convert Solidity code to Cairo. Nevertheless, this transpiler currently lacks support for various Solidity features and falls short of achieving the same level of EVM compatibility as zkSync V2.