Evaluate whether a delivery stream meets the isochronous service obligation of ECSS-E-ST-50C clause 5.6.14.4, where a service promised at a fixed cadence has to arrive on that cadence and not merely at the right average rate. Compute every delivery's deviation from the ideal grid, the peak-to-peak jitter, the playout buffer that would re-time the stream, and the smallest tolerance the run would have passed under, then separate a rate error that walks the stream off the grid from bounded jitter that stays put. Use when accepting or reviewing an isochronous downlink, playback or synchronous bus service. Trigger: ecss, e-st-50-communications, isochronous-delivery-jitter, iso…
