In this lesson, you are going to learn one of the unique features of Scroll that makes Scroll stand out from the rest. Let’s start with learning why we need this system and then you are going to learn what this system is and how it works.

Why is a Robust Verification System Crucial?

Scaling blockchains like Ethereum while maintaining security and user experience is a complex challenge. A single point of verification for transactions leaves potential risks. Here's where Scroll stands apart with its innovative multi-prover system. Just like having multiple experts review a complex project, utilizing multiple provers significantly boosts Scroll's reliability and security.

What is a Prover?

In the world of ZK-Rollups like Scroll, provers play a pivotal role. They are specialized systems with two key functions:

• Efficient Organization: A prover gathers transactions on the Scroll network and neatly arranges them into blocks.
• Generating Trust: It employs advanced cryptographic techniques to generate a compact mathematical proof. This proof irrefutably validates that every transaction within the block is legitimate, plays by the rules, and guarantees accuracy – all without revealing the sensitive details of the transactions themselves.

Scroll's Unique Strengths

• Unmatched Security: Scroll takes security to the next level! Unlike solutions relying on a single prover or a small group, Scroll's multi-prover system is like having a security task force. Multiple independent provers constantly cross-check each other's work, making it virtually impossible to slip fraudulent activity past the system.
• ZK-Rollup Compatibility: Scroll doesn't just claim to be ZK compatible – it leads the way. It's designed with seamless integration with all the powerful tools and ecosystems of Ethereum. This means developers can keep using the tools and languages they already know.
• Developer-Centric Approach: Every aspect of Scroll is built with developers top of mind. It offers full compatibility with the Ethereum Virtual Machine (EVM), ensuring a smooth transition for existing projects. Developers have the flexibility to leverage familiar tools and coding languages without steep learning curves.

How Scroll's Multi-Prover System Works

• Transaction Pool: Transactions initiated on Scroll gather in a pool.
• Competitive Security: A network of provers compete to take a batch of transactions from the pool to create the next block. This competition ensures only the most efficient and reliable provers get the job.
• Bulletproof Validation: Other provers take on the role of vigilant auditors, meticulously reviewing the work of the winning prover. Any discrepancies or errors are immediately flagged, preventing faulty work from getting through.
• Secured by Ethereum: Only when a proof has passed this rigorous multi-prover check does it get submitted to the Ethereum blockchain, solidifying its validity and anchoring Scroll's security to Ethereum.

Scroll’s TEE Prover Approach

Scroll's multi-prover system is further enhanced by incorporating a Trusted Execution Environment (TEE) prover. A Trusted Execution Environment (TEE) is a secure area within a processor that ensures code and data loaded inside are protected with confidentiality and integrity. The TEE prover utilizes this secure enclave to perform critical verification tasks, ensuring that sensitive operations are isolated from the main operating environment, thus preventing tampering and unauthorized access.

Here’s how it adds value:

• SGX Prover: This off-chain component uses the SGX technology to securely execute and validate transactions within a hardware-protected enclave. It checks that the post-state root matches the existing state root after block execution and submits the Proof of Execution (PoE) to the SGX Verifier.
• SGX Verifier: An on-chain component, it verifies the correctness of state transitions proposed by the SGX Prover. The SGX Verifier also authenticates attestation reports from the Intel SGX enclave, ensuring the integrity and trustworthiness of the prover.

TEEs provide hardware-grade isolation, ensuring computations within the secure enclave remain tamper-proof and verifiable. This adds an extra layer of security by distributing trust across different proof mechanisms, reducing overheads, and enhancing resilience against systemic vulnerabilities​.

If you’d like to learn more about Scroll’s TEE approach, you can check out this article.

Real-World Analogy

Think of a high-stakes exam with a panel of professors grading it. This multi-expert evaluation ensures unbiased results and builds confidence in the outcome. Similarly, Scroll's multi-prover system instills trust in the network's integrity.

Scroll's multi-prover system is a force for innovation, raising the bar for security and scalability. By providing bulletproof transaction guarantees, compatibility with existing Ethereum tools, and a smooth developer experience, Scroll positions itself as the ideal platform for the next generation of decentralized applications.