'tcpdump_mesa' (Geedge's tcpdump fork, packaged as an RPM dependency of the sapp DPI role) adds a '-g' greedy-jump mode that filters and captures by the innermost IP/port inside tunneled/encapsulated traffic (coordinated with sapp over a control connection), and can capture packets sapp routes around DDoS-bypass handling -- confirming TSG's packet-capture tooling is explicitly built to see through tunnel encapsulation rather than only inspecting the outer transport.

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 same SAPP manual documents mrzcpd's inline (串联) packet-re-injection subcomponent mrtunnat, configured at /opt/mrzcpd/etc/mrtunnat.conf: use_recent_tunnel=1 allows it to inject a packet with no prior session record, and use_link_info_table=1 makes it validate outer MAC, link_id, link_dir, and inner MAC against a live link-state table at /run/mrzcpd/mrmonit.tunnat before re-injecting a censor-forged packet onto the correct physical link.

An internal SAPP platform training/reference manual (marked "Geedge Networks Confidential And Proprietary") gives SAPP's full name as "Stream Analyse Process Platform" and documents its three-tier plugin architecture (platform / protocol-parsing / business layers, each loaded via dlopen), inline and mirror deployment modes at a stated 10-40 Gbps per box, tunnel-protocol support (GRE/MPLS/IPIP/IPv6-over-IPv4/Teredo), and the MESA_kill_tcp() plugin API that forges and sends RST packets to sever a monitored TCP connection, with the manual noting it was "originally used in mirror mode to send RST packets to block a TCP connection" and auto-retries until the connection is confirmed dead.

Two 2023 self-test reports (one co-signed by the Institute of Information Engineering, Chinese Academy of Sciences) describe a dedicated capture appliance, hardware model MESA-NF-3100 (2U, Xeon E5-2640V4, 256GB RAM, dual XL710 10GbE NICs, 8Gbps/device and 20-27Gbps/cluster), whose mirror-capture driver is started via `systemctl start mrzpd` (mrzcpd) alongside the sapp process, feeding a downstream 'nirvana_server' component.

A June 2021 internal report measures a live in-network TLS-interception pilot: one sapp instance ingests raw ciphertext via mrzcpd while a second ingests plaintext from a "third-party decryption platform" over a Unix domain socket, and one hour of production traffic on a live front-end (10.187.0.2) shows the decryption platform successfully produced plaintext for 4.85% of raw traffic bytes and 7.4% of all port-443 TCP connections, with an average end-to-end decrypt latency of 1741ms (median 460ms, up to 6000ms) between first ciphertext byte and the resulting plaintext HTTP GET.

sapp's internal architecture guide documents three deployment topologies (mirror/passive-tap, inline, dual-arm transparent) and four distinct methods for injecting blocking packets back onto the wire, including a MAC-in-MAC scheme that extracts device/link IDs from mirrored traffic's source MAC field to route an injected packet to the correct physically separate inline device over VXLAN when multiple injection points exist.