Benchmarking Bitcoin Script Evaluation for the Varops Budget (Great Script Restoration)

The discussion revolves around the proposed Bitcoin Improvement Proposals (BIPs) which suggest introducing a new sigversion to exist alongside the current ones without altering them. This new sigversion would be integrated through a tapscript leaf and is designed to comply with a varops budget, potentially incorporating Generalized Schnorr Signatures (GSR). The intention behind leaving the existing sigversions unchanged ensures that the introduction of this new sigversion does not negatively impact the performance or functionality of the current base tapscript leaf.

By establishing a computational budget for the new sigversion, the goal is to ensure that scripts utilizing GSR will not perform slower than the worst-case scenarios under the current system, across the majority of machines. This consideration is crucial from a Denial of Service (DoS) attack perspective, as it addresses potential vulnerabilities by not overly restricting the computational capabilities of the new sigversion compared to existing ones. The rationale is that since attackers can target any sigversion, making the new one disproportionately restrictive wouldn't offer additional security benefits but rather limit its efficiency and applicability unnecessarily.

There is a suggestion about possibly extending the varops budget to include existing sigversions, indicating a significant shift in discussion focus. This implies that adjusting the computational budget constraints for current sigversions might warrant a separate, comprehensive debate, underscoring the complexity and multifaceted nature of implementing changes within Bitcoin’s scripting infrastructure.