Frame-based error indications
These frame-based errors can be indicated in the extended packet descriptor 9:
Ethernet small frame error
If the ISL, Ethernet and VLAN/MPLS 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.
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.
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.