A MESA Lab traffic-fingerprinting dossier builds DPI detection material for third-party remote-access/tunneling software (Sunlogin/花生壳, TeamViewer, and a self-hosted OpenVPN test deployment) by cataloguing each tool's domains/IPs, TLS SNI values, HTTP User-Agent and Host headers, and UDP ports, with traffic captured and labeled per discrete user action (login, add device, start remote session, quit, logout) — exactly the raw material an app-identification signature system would be built from.

Exported AppSketch/MAAT signature-object JSON shows named per-VPN detection rules combining multiple independent vectors: CyberGhost's WireGuard variant is matched by a hex UDP-payload pattern (04000000*), destination port 1337, and ip.proto=17 together (signature cyberghostvpn_wireguard); Windscribe's OpenVPN control channel is matched by two offset-anchored hex byte patterns plus an exact 86-byte payload length (windscribevpn_openvpn_payload); and ExpressVPN is matched independently via a literal JA3 hash (ssl.analysis.ja3), FQDN strings (expressapisv2.com, www.expressvpn.works), and a large enumerated IP list (700+ individual ip.dst entries observed before the 200KB text-extraction cutoff).

An internal app-fingerprint engineering document (identical content filed under two separate artifact ids) catalogs precise per-action (login/create/upload/ download/share/delete) DNS, SNI, and certificate-CN signatures for identifying use of specific cloud-collaboration apps from traffic alone, covering foreign platforms Zoom and Office365 alongside domestic apps (Huawei WeLink, Feishu, DingTalk, WeCom, Shimo Docs, CSTCloud drive), using tools like myssl.com for active certificate/IP verification of each signature.

Raw TSG session_record export logs dated Nov 2024, tagged device_group 'YGN-MYTEL' (Yangon, Mytel), directly corroborate the leak's M22=Myanmar/Mytel/Yangon site-codename mapping with live production data: individual SSL sessions are classified by app as 'Hotspot Shield VPN' (destination get.adobe.com, likely a fronting/CDN endpoint) and allowed under a named whitelist rule 'whitelist_102024', geolocated client-side as Myanmar.Yangon.Yangon.

The Transformer_master.h header (part of the Maat/sapp DPI framework, dated 2023-05-04) defines a region-keyed DNS response-forgery subsystem (MSG_OPT_DNS_CHEAT_TYPE/RCODE/STRATEGY/RECORD/TTL, DNS_FAKE_INFO/DNS_FAKE_IP tables, TF_get_dns_response_strategy_id(user_region)) used specifically by the block ("FD") action path, plus a dedicated function to classify whether a detected L7 protocol is a VPN (TF_is_L7_vpn_prot), and native extraction of TLS JA3/JA3S client and server fingerprints.

MESA_Platform's "quic" module (built and packaged as stellar-on-sapp/sapp RPMs) implements SNI/User-Agent extraction from both cleartext GQUIC (versions 23-59) and encrypted IETF QUIC RFC9000 ClientHello payloads, and supports a QUIC SNI whitelist -- i.e. the DPI pipeline decrypts/parses encrypted QUIC handshakes to recover the destination domain rather than being blocked by QUIC's encryption.

TSG's QUIC-parsing layer decrypts QUIC ClientHello payloads and parses a user-agent-like parameter from the decrypted content, deployed at the Ethiopia (E21) DIR-IGW site. A missing bounds check on this field caused a watchdog-timeout crash, confirmed via a MESA_Platform/quic GitLab commit (git.mesalab.cn/MESA_Platform/quic).