iSCSI: 12-97 Bit Rule

[pat_thaler@agilent.com]

Julian,

 

The bit rule added to 12-97 (1.3.4 page 31) is inconsistant with the clauses above it: Word Rule,  Half-Word Rule and Byte Rule.

 

It says "when the sequence of bits has a positional significance (e.g., a modulo 2 polynomial) then bit 7 of the lowest numbered byte is considered the most significant bit (2**n), followed by ...."

 

When bits represent a number, they have positional significance so that sentence applies. However, the other rules apply the opposite significance to the bits within each byte.

 

Also, note that bits represent polynomials at other times than the CRC such as for the purpose of authentication or encryption algorithms and those algorithms do not necessarily use the bit significance of the Bit Rule. The bit rule only applies to bit significance for CRC calculation.

 

Bit Rule should be CRC Bit Rule and the associated text should make it clear that it only applies to the CRC calculation. Since it only applies there, it would be kinder to the reader to put the text in 11.1 rather than making the reader of 11.1 look nearly 200 pages back in the spec.

 

Regards,

Pat