1 | initial version |
The start of the Zero Window condition was when the receiver sent the first Zero Window packet. The other Zero Window packets are repeating that notification. So, you should take the time from the first Zero Window packet to the first packet with a non-zero window size.
If your Time column is still set to the default (Seconds Since Beginning of Capture), you can right-click on the first Zero Window packet and click "Set/Unset Time Reference." That makes that packet a new time-zero point. You can then just look at the time on the Window Update packet and see how much time has elapsed.