A MESA lab engineering project codenamed "SAT" builds a user-station identification module on top of TSG, using the MAAT rule-file format for its front-end/back-end policy (PZ) interface, and ingests LTE mobile-network-element traffic (S1-U interface -- SGW/PGW/eNodeB/MME, captured via a simulated Docker SDR environment) to write subscriber-station status into a "TSG-Radius" table.
SAT 用户站 PZ、日志接口确认 最终确认使用原 PZ 线 MAAT 文件格式作为 SAT 前后端 PZ 接口 / LTE 网元流量模拟 在 vps 上部署 docker SDR 模拟 LTE 环境,采集 SGW/PGW/eNodeB/MME 网元样例流量 / 完成用户站状态表转存入TSG-Radius表代码开发
Related findings
An internal TSG operations/troubleshooting manual lays out TSG's full traffic pipeline (NIC -> mrzcpd/marsio capture driver -> sapp DPI engine -> firewall/proxy(KNI->TFE)/active-defense/WAN-NAT policy branches) and shows engineers using maat_redis_tool to pull the live Redis-synced blocking policy tables (TSG_SECURITY_COMPILE, TSG_OBJ_IP_ADDR, TSG_OBJ_APP_ID) and filter them by numeric policy/object ID to debug why a block rule isn't firing.
The internal 'MAAT网络流处理配置统一描述框架' engineering manual (v3.1.20, author 郑超, 2021) documents MAAT's Redis-synced rule-compilation framework and its RuleScan/Hyperscan-based pattern-matching engine (libmaatframe.so / librulescan), and records that RuleScan's fast-scan feature caused a production outage on 2019-03-19 and has been disabled ever since.
Side-by-side internal performance comparison across Xinjiang (China Mobile carrier deployment, hostname cmcc-xj-server1-sapp-244), Fujian (domestic), and Ethiopia (E21) explicitly references the same 'app_sketch_maat' diagnostic log format at all three sites, confirming the identical AppSketch app-fingerprinting stack is used for domestic Xinjiang surveillance and for the exported Ethiopia deployment.
A September 2023 IIE/CAS-authored test report for a "流量汇接处理子系统" (Traffic Aggregation Processing Subsystem, built on the sapp/durain_master_maat stack) confirms the system is architected to ingest and process a combined 27Gbps of raw traffic from two aggregation points simultaneously: a general "互联网汇聚口" (Internet aggregation port) and a "政务外网汇聚口" (Government Extranet aggregation port) — i.e. the same DPI processing pipeline documented for public-internet censorship is also deployed against China's internal government-network traffic.
TSG's DPI signature engine is organized around named internal components confirmed by config paths and error logs: SAPP (installed at /home/mesasoft/sapp_run or /opt/tsg/sapp), MAAT (config at .../tsgconf/maat.conf, tied to a Redis-backed APP_SIG_SESSION_ATTRIBUTE_STRING table), and App-SketchDB (a versioned, centrally-maintained app-identification signature database pulled periodically by field deployments). One deployment's provincial gateway alone had 1,667 TCP/UDP first-packet payload signature entries active (396 at the IDC site), confirming payload-prefix matching as a live, large-scale detection method, including custom byte-prefix entries for DingTalk and WeChat.
Session-log exports from a Beijing test/demo TSG device ("XXG-TSG-BJ") show live "Deny" enforcement actions (security_rule_list "Deny_VPNHero", "deny_TowerVPN") against traffic the app-ID engine classified with nested app chains "VPNHero" and "OPENVPN.TowerVPN.Psiphon Provider.Psiphon-Server" -- i.e. TowerVPN is specifically tagged internally as riding on Psiphon infrastructure, and both it and VPNHero are actively blocked, not just logged, on this device.