The AV/frag_rssb tool performs fragment reassembly of intercepted network streams to extract audio/video and VoIP content (source files frag_av.c, frag_voip.c, "sip_send_survey_log SIP to RTP"), with "sifter" pattern templates specifically for YouTube, Tudou, DASH, HLS and OSMF media streams. Config files main_k.conf/frag_reassembly_k.conf and a K_PROJECT build macro indicate a customer-specific build variant labeled "K" (consistent with the K18/Kazakhstan site codename convention used elsewhere in this corpus).

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.

An internal design note for a 'Shadowsocks traffic parsing/restoration module' describes decrypting captured Shadowsocks payloads back to the original HTTP request/response, given a known pre-shared key (AES-256-CFB, MD5-derived key, IV embedded in the stream).

Beyond VPN/circumvention tools, the same exported signature format is used at large scale for ordinary consumer apps — e.g. a Bank of Communications ('jiaotongyinhang') signature matches four exact-match DNS query names (download1.bankcomm.com, mobile.95559.com.cn, mbank.95559.com.cn, monitor.bankcomm.cn), and other entries (huolala, qidiandushu, zhihu) use the newer dns.qname/ssl.sni/http.host/quic.sni four-vector pattern per app. A companion artifact (70707a230d7d) is a flat list of thousands of specific URL paths (not just domains) spanning news, e-commerce, government-adjacent, and international press sites — consistent with the fqdn_category_list field seen in TSG's session-log schema, i.e. this is categorization/classification reference data, not solely a VPN blocklist.

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).

A dedicated AppSketch/MAAT signature object named 'Psiphon-Volunteer-IP' (signature_id 4054) blocklists specific IPv4/IPv6 CIDR ranges by ip.dst regardless of port (192.122.190.0/24, 2001:48a8:687f:1::/64, 141.219.0.0/16, and more), i.e. Geedge maintains infrastructure-level blocking of known Psiphon volunteer-hosted proxy server ranges rather than relying solely on app/protocol fingerprinting.