Markers

[pat_thaler@agilent.com]

I was reading the text of Appendix A and noticed an ambiguity.

The text says:
The Marker indicates the offset to the next iSCSI PDU header. The 
   Marker is eight bytes in length and contains two 32-bit offset fields 
   that indicate how many bytes to skip in the TCP stream in order to 
   find the next iSCSI PDU header. The marker uses two copies of the 
   pointer so that a marker that spans a TCP packet boundary should 
   leave at least one valid copy in one of the packets.

From this text, it is not clear whether the two "copies" of the marker are identical copies or whether each marker specifies how many bytes to skip from its position in the stream. It also isn't entirely clear where the count of bytes to skip starts (which is related to the first). 

For example, if a PDU starts right after a marker:

      Next-iSCSI-PDU-start pointer - copy #1
      Next-iSCSI-PDU-start pointer - copy #2
      PDU header start

Do Copy #1 and Copy #2 both contain 0x00000000, or does copy #1 contain 0x00000004 because the packet starts 4 bytes after copy 1 while copy #2 contains 0x00000000
because the packet starts 0 bytes after copy 2? 

Since "copy" implies they are the same, I think they should both contain 0x00000000.

This could be clarified by adding, "The count of bytes begins with the first byte after the Marker." One could also include the example above.

Regards,
Pat