In article , Arnold Nipper wrote: :Is there a chance to look at the trailer/CRC of an Ethernet frame to see :whether two frames which where caught by tethereal are distinct or the :same due to L2 looping?
Interesting; it sounds plausible, to the extent that duplicate packets are unlikely in the protocol (e.g., tcp has sequence numbers but other protocols do not necessarily have unique information.)
:Example: I've a set of ~ 9200 frames, where station X.X.X.X is broadcast :arping for IP Y.Y.Y.Y. When looking at the trailer like in
:Frame 316560 (60 bytes on wire, 60 bytes captured)
: Packet Length: 60 bytes
: Type: ARP (0x0806) : Trailer: 0000020100020100430500D89EBC6C30...
The normal ethernet trailer is only 4 bytes long . RFC 893 suggests a protocol for much much larger trailers, but then the capture length would have been much higher.
This leads me to suggest that what is being shown as Trailer: is not what is usually referred to as "trailer" in ethernet packets.