How do you view Optimism fraud proof being adjusted to permissioned due to security issues?

Author: HAOTIAN

Recently, @Optimism has been questioned by the overseas community due to security audit issues with the Fault Proof System. After major security issues were discovered in the original permissionless fraud proof mechanism, the OP Foundation actually proposed to hard fork to fix the problem and convert it into a licensed proof? What exactly happened?

1) Simply put: Fault Proof System is a mechanism for verifying the correctness of the Layer2 network state. Anyone can submit the L2 state to the dispute virtual machine on L1 without permission and accept challenges from others. If the challenge is successful, a reward and punishment mechanism will be triggered.

This is the fraud proof mechanism that must exist for the OP-Rollup mechanism to ensure security. The launch of the Fault Proof System in June can be regarded as a remedy for the market's long-standing criticism of the OP Stack's lack of an effective challenge mechanism.

2) However, a recent community-driven audit found multiple vulnerabilities in the fraud proof system, but the response of the Optimism Foundation was surprising:

1. The fraud proof VM opcode-level vulnerability was regarded as a minor security vulnerability;

2. The fraud proof system was excluded from the scope of external audits;

3. The permissionless mechanism of the fraud proof was temporarily adjusted to a permissioned mechanism, and a hard fork plan called Granite was proposed to solve the security problem;

As a result, people have to doubt the meaning and effectiveness of the so-called Fault Proof System.

3) How do you view this matter? In my opinion:

1. Optimism launched the Fault Proof System entirely to further expand the necessary security challenge mechanism of the OP Stack camp. The market has become "optimistic" about whether Optimism itself has such a challenge mechanism;

2. The Fault Proof System is indeed sophisticated and complex in structure. Most of the states can be verified locally in L2, and only some key parts are pushed to the fault virtual machine of L1 for judgment. Yes, a virtual machine with specific op code is developed, which can ensure the low cost of L1 verification while ensuring security;

3. The Fault Proof System was changed from unlicensed to licensed, and was urgently disabled, which also exposed the excessive rights of the OP Foundation and the Multi-Signature Security Committee. Fraud proofs are under the control of the Security Committee even without permission;

4. Optimism has fallen behind in achieving the security and decentralization goals of Stage 1, at least compared with Arbitrum in the same camp, and ZK-Rollup's leading advantage in technology will be further valued.