A 2018-2019 IIE-authored repo (IPReuse/vpn_cgi) implements a Django CGI service ("VPN_CGI") with a Redis-backed IP-statistics module (stat_ip_redis.py), built by a team explicitly named "IPReuse" — early (pre-2020) tooling for tracking/managing VPN-associated IP addresses, structurally similar in purpose to the later-documented CyberNarrator 'vpn-thwarting' IP-harvesting/blocklist pipeline, though not confirmed to be the same lineage.

TSG/CM ships with pre-built, first-class 'Learning Object' entries specifically for Freegate (Object ID 18) and Psiphon3 (Object ID 19), plus a generic 'Top Server IP' object (ID 20) -- default product features, not customer-commissioned custom signatures. The Psiphon3 object auto-learns and dynamically updates a live blocklist that reached roughly 70,000 IPs at one deployment before a database issue temporarily dropped it to ~50,000.

A crash/perf bug report reveals Geedge's MAAT rule engine (libmaatframe.so, using Intel Hyperscan for literal/regex matching) running with 545,441 FQDN blocking rules and 404,141 IP address blocking rules loaded in a single instance as of 2024; loading 500,000 new FQDN rules via the full Hyperscan path took ~95 minutes, addressed by an automatic fallback to a second engine ("Rulescan") above 50,000 rules.

Geedge extracted and analyzed Betternet VPN's underlying protocols (WireGuard, a proprietary "Hydra" protocol using spoofed-domain TLS 1.2, and IKEv2), and found the Hydra protocol could be "completely blocked" via JA3 TLS fingerprinting; IKEv2 was blocked via UDP port 500/4500 policy, and thousands of VPN server IPs were extracted as a supplementary IP blocklist.

Geedge extracted ProtonVPN server IPs using the app's own debug-log output to find its server-list API endpoint, directly querying it to harvest ~5,800 server IPs, then used automated repeated connection cycling to extract ~200 additional rotating IPs after the initial list was blocked; the app was subsequently reported fully blocked on Android, iOS, and Windows.

The PanGu/pangu_valve repo implements MAAT's live blocking/throttling distribution layer: it consumes Redis-backed MAAT config tables (APP_DOMAIN, APP_POLICY, LIMIT_DOMAIN, APP_STATIC_SEV_IP, APP_DYN_SEV_IP_CB, LIMIT_DYN_IP_CB) and pushes reference-counted domain/IP block and rate-limit rules to inline ("串联设备") network devices, scoped per inline-device business ID.

Geedge runs an ongoing, largely manual weekly signature-extraction program against commercial VPN apps (LetsVPN, Betternet, VPNLITE, and a ~80-app batch), combining server-IP lists, FQDN patterns, and payload/SNI/Host/User-Agent signatures, tested for blocking efficacy and false-positive rate before rollout. VPNLITE was fingerprinted via TCP direct-connect on ports 18000/3320/8099 plus TLS to randomized .xyz/.info subdomains on Cloudflare ranges (104.21.0.0/16, 172.67.0.0/16).