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The TCP window of a connection in hardware, checked there. Measured, 2026-10-22

The bench the evening it was measured: on the left screen the driver's code, octep_tcp_from_pf - a connection's window made from pf's numbers; on the right a run of the series, segments outside the window dropped on the XGS 136 and four streams through both appliances; below them the XGS 136, opened, and the XGS 3300

Until this, a TCP connection the coprocessor forwarded had its window checked by nobody: the driver sent its connection entry with the TCP block at zero and the check off, and marked pf's state sloppy, because pf would otherwise drop the connection's frames against a window it no longer saw move (679, the discovery).

The whole page, with how it was taken and what it does not show: The TCP window of a connection in hardware, checked there. Measured, 2026-10-22.

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