Technical forensic specification explaining how BotRefund analyzes browser environments and network invariants to distinguish novel retail browsers from server-side automation.
Legitimate consumer sessions originate directly from residential, cellular (LTE/5G), or corporate office ISPs. Network packets exhibit standard unfragmented Maximum Transmission Units (MTU 1500, TCP MSS >= 1460 bytes) without tunnel encapsulation headers, and domain lookups resolve via local ISP nameservers.
Automated scraping rings route clicks through commercial datacenter servers or residential proxy tunnels. Tunnel encapsulation (WireGuard/SOCKS5) clamps TCP SYN MSS to <= 1420 bytes, leaks residential IPs via WebRTC, or routes DNS queries through discordant overseas resolvers.
After the session ends, the server probes a small fixed set of conventional ports on the trusted observed public IP. A recognizable SOCKS5 negotiation or HTTP proxy response (including a 407 authentication challenge) shows that proxy infrastructure was publicly reachable from that address. This is supporting server-observed evidence for an invalid-traffic review, not proof that the visitor personally operated the listener or that a specific provider supplied it.
Ad Platform Fraud Classification: Under Google Ads Invalid Traffic guidelines (Automated Click Activity) and Meta Advertising Integrity standards, sessions exhibiting Public Proxy Listener violate fundamental consumer hardware invariants. They fail deterministic silicon rasterization, protocol compliance, or neuromuscular biometrics.
Why This Proves Non-Human Origin: Genuine consumer browsers on retail operating systems execute this API natively with verified hardware backing. Server software (headless cloud containers, unpatched automation harnesses, and proxy tunnels) cannot replicate this execution environment without incurring prohibitive server hardware costs.
Evidence Dossier Invariants: Each disputed click in our export packet matches an immutable server-side timestamp, landing URL, GCLID/fbclid, and observed IP address with zero client-side tamperability.
Human Baseline & Exception Scenario: Shared carrier-grade NAT, residential gateways, or other shared public addresses can associate a listener with the wrong individual. A negative result is inconclusive because most residential and mobile proxy nodes use outbound persistent connections and expose no public listener.
BotRefund operates a multi-vector ensemble model. This signal adds objective forensic weight to the session dossier but never acts in isolation. Positive verdicts require corroboration across network routing, hardware silicon, and cursor kinematics to guarantee 99% precision.
This signal registers an objective, mathematically verifiable anomaly on the session ledger.
BotRefund correlates L4 packet timing, GPU silicon, and cursor jerk before finalizing risk.
Compiled directly into Google Ads and Meta refund packets with verified click IDs and server logs.