The slippery eel of CRC, RE: iSCSI: 12-97 Bit Rule

[Bill Studenmund <wrstuden@wasabisystems.com>]

On Thu, 13 Jun 2002, CAVANNA,VICENTE V (A-Roseville,ex1) wrote:

> I believe Bill is correct. The receiver, unlike the transmitter,
> should not complement the remainder if he expects to get 0x1c2d19ed.
>
> I am afraid I may be reponsible for this mistake during an email
> exchange I and others had with Julian recently. Julian and those
> others must have trusted me a little too much. Sorry Julian and
> others.

It seems like we're changing the text to be clearer for some folks, and
unfortunately making it more confusing for others. It's like trying to
catch an eel, as soon as we get a second hand on it, it pops out of the
first.

In addition to fixing the above, to be perfectly clear, perhaps we should
mention that when calculating the CRC over a correctly recevied message +
CRC, were the receiver to append the result of this calculation to the
received message + CRC, it would always append the octed stream "c7 4b 67
48". This example is meant in the spirit of section B.4 where we have
clear octets to compare against. Actually this bit should probably go in
section B4 at the end.

Take care,

Bill