Refining Proxy Detection for ISP?

Following up on previous discussions regarding ISP identification failures, my current technical block centers on accurately discerning legitimate ISP-assigned IPs from various proxy types, particularly residential ones. This specifically relates to improving proxy detection accuracy.

• Problem Statement: Standard IP-to-ISP mapping tools often falter with sophisticated proxy usage, leading to skewed or incorrect ISP identification results.
• Specific Inquiry: I'm seeking highly effective, low-latency techniques or APIs that can reliably differentiate between residential proxy IPs and genuine end-user ISP connections to improve identification accuracy.