A ClickHouse SQL query against table tsg_galaxy_v3.session_record_local implements a heuristic for flagging likely proxy/circumvention-tool usage: within 5-second windows, it flags any client IP that connects to 30+ distinct server IPs on high ports (>=10000) with small, tightly-bounded packet counts (6-15 sent, 4-15 received) where the session's application-layer protocol is unclassified (app_transition = 'unknown'). "tsg_galaxy_v3" indicates a named TSG data-warehouse/analytics layer distinct from the sapp/maat real-time inspection path.
FROM tsg_galaxy_v3.session_record_local WHERE decoded_as = 'BASE' AND app_transition = 'unknown' AND server_port >= 10000 AND sent_pkts BETWEEN 6 AND 15 AND received_pkts BETWEEN 4 AND 15 ... HAVING unique_servers_count >= 30 -- 至少30个不同IP
Defense implications
- A client that fans out to many small proxy/relay connections on high ports in a short window (e.g. a client rotating across many bridges/servers) risks tripping this specific unknown-protocol fan-out heuristic even if each individual connection's protocol itself evades classification; connection-count/rate randomization across servers per window may matter as much as per-connection obfuscation.
Related findings
A dedicated internal "运营商前端分析团队" (Carrier Front-end Analysis Team) produces weekly, carrier-specific traffic-analysis reports explicitly titled "新疆移动流量分析报告" (Xinjiang Mobile Traffic Analysis Report) and "新疆联通流量分析报告" (Xinjiang Unicom Traffic Analysis Report), with instances dated from at least July 2022 through March 2024. One instance (Xinjiang Mobile, 2023-05-15) reports total carrier bandwidth of 4.4Tbps (1Tbps access bandwidth), 27.34PB of weekly throughput, 123 distinct identified application-layer protocols, and a section (4.1, pages 17+) explicitly tracking server IP/location for 28 named overseas apps (BBC, Discord, ESPN, Facebook, Gmail, Google, Hulu, Instagram, Netflix, Reddit, Skype, Telegram, Twitter, Uber, WhatsApp, Wikipedia, YouTube, Zoom, etc.).
A weekly "新疆移动流量分析报告" (Xinjiang Mobile Traffic Analysis Report), authored by the "运营商前端分析团队" (Carrier Front-End Analysis Team), directly ties the SNI/Server-IP overseas- APP report format to the China Mobile Xinjiang branch specifically, and states the pipeline identifies 126 distinct application-layer protocols including multi-layer tunnel nesting such as STUN.DTLS and STUN.RTP.RTCP.DTLS — i.e. it decomposes and classifies nested WebRTC-style transport stacks, not just top-level TLS/QUIC.
Multiple domestic IDC traffic-monitoring reports rank "Freegate" (a well-known GFW-circumvention tool) as a distinct, named top-10 application by traffic volume alongside Bytedance/Tencent/Alibaba/Baidu, with peak 18.92 Gbps and average 5.9 Gbps in one 2022-07-07 report -- confirming Freegate has its own dedicated app-ID classifier tracked at carrier-comparable traffic scale, not merely a low-volume/rare signature.
A performance bug at a domestic Xinjiang test site (25-70Gbps) traced packet-processing lock contention to a plugin named "tsg_vulpes" calling an ONNX Runtime model for real-time "encrypted voice recognition" on live traffic; disabling this ML classifier resolved packet loss, indicating it's an optional, performance-costly add-on.
MESA Lab engineering logs (2020) describe development and TSG-environment testing of a SAPP plugin that identifies encrypted audio/video traffic and distinguishes on-demand from live streams. The workflow uses Fiddler (a TLS MITM proxy) to decrypt traffic client-side and auto-label training data for the underlying ML model, and required a dlopen() workaround to load libpython.so for the model at runtime.
Recurring weekly '新疆移动流量分析报告' / '新疆联通流量分析报告' (Xinjiang Mobile / Xinjiang Unicom traffic analysis reports) document a domestic monitoring deployment covering China Mobile Xinjiang (total capacity 4.4Tbps, ~1Tbps actively monitored, observed peak 1275.49Gbps) and China Unicom Xinjiang, breaking traffic into intra-Xinjiang, domestic, and overseas flows and reproducing the same per-foreign-platform (YouTube/Google/Facebook/Twitter/Instagram/Telegram/WhatsApp/etc.) server-IP breakdown used in the national TSG SNI reports, at a carrier-and-province-specific granularity.