Frame-based error indications
These frame-based errors can be indicated in the extended packet descriptor 9:
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Ethernet small frame error
If the ISL, Ethernet and VLAN/MPLS/VN-Tag frame decode shows that the frame is too small for the applied protocols, an Ethernet small frame error is indicated in the frame decoder status word.
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Ethernet large frame error
If the frame is a large frame (see Large frames), an Ethernet large frame error is indicated for the frame. It is indicated in the frame decoder status word.
FCS error flag
A frame is flagged for FCS violation if:
- It is smaller than 18 bytes, that is it is not a well-formed Ethernet frame and is considered a fragment.
- It is larger than or equal to 18 bytes but smaller than or equal to 10,000, and the last 4 octets do not match the recalculated frame CRC.
- It is larger than 10,000 bytes, that is it is a hard-sliced frame.
- It has a code violation.
- It has an alignment error.
FCS errors are always flagged in the standard packet descriptor (see DN-0449), but are not always counted in the statistics (see Statistics).
Hard-sliced flag
A frame is flagged for hard-slicing if the frame length is larger than 10,000 bytes.
Code violation flag
A frame is flagged for code violation if it contains code violation bit errors.