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CASE 01 · FLAGSHIP · SURFACE 01

PCAP explainer

Upload a capture, get a Stevens-style annotated decode: sequence, window, RTT, retransmit pathology.

Screenshots from the current build. Select one to open it full size.

ROOT CAUSE ANALYSIS
ROOT CAUSE ANALYSIS
Root cause analysis panel: packet loss and retransmissions at 50% confidence, flagged preliminary, with evidence cards for retransmission count, CWND collapse and ACK compression bursts, and prioritized next steps.
Figure 1.2  Root cause, with the confidence stated and the evidence behind it. Here the verdict is loss and retransmission at 50%, flagged preliminary rather than overstated.
RTT OVER TIME
RTT OVER TIME
RTT over time chart for one flow: client-to-server and server-to-client RTT lines with queue and throughput overlays, layer toggles for cwnd, BDP, phases, TCP signals, SACK gaps and TCP state, and zoom controls.
Figure 1.3  RTT per direction across the flow, with queue and throughput overlays. Each layer toggles independently, and hovering syncs highlights with the packet list.
EVENTS & PACKETS
EVENTS & PACKETS
Detected events list — phase_transition and bdp_state entries keyed to packet numbers — above the packet list: SYN, SYN+ACK, ACK and PSH+ACK rows with timestamps, direction, sequence, acknowledgment and length.
Figure 1.4  The decode underneath. Detected events are keyed to packet numbers, and every packet is timestamped from the first SYN, tagged by direction, and shown with its sequence and ack state.