VIAVI TestCenter: Why do I see FCS errors on the STC GUI Port counters when receiving IEEE802.1QBU preempted fragments?

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VIAVI TestCenter: Why do I see FCS errors on the STC GUI Port counters when receiving IEEE802.1QBU preempted fragments?
• For Preemption packets, Initial Frag, Continuation frag will have mCRC calculated which is different from FCS. • STC calculates FCS based on each stream since it cannot calculate mCRC. • We can ignore Rx FCS Error Frame count values for Preemption streams. • Preempted fragments is validated using TestCenter IQ, Qbu results • Invalid Fragment Count should represent bad mCRC.