RE: iwarp-tech Conformance Question

Hi Barry,

my understanding is that CRCs are required unless both sides set the CRC bit to '0'.  If the reply frame from the responder has the C bit set to zero after the request frame had it set to one, then CRCs are required.  The responder may not be using them on receive, but it has to accept them from the initiator and it has to generate them on transmit 

--jc

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of Barry Reinhold
> Sent: Friday, November 12, 2004 2:43 PM
> To: RDDP
> Cc: [email protected]
> Subject: iwarp-tech Conformance Question
> 
> 
> Working on an interoperability issue related to section 
> 3.6.1.1 (CRC bit
> paragraph) of MPA, which states:
> 
> This bit (CRC bit) declares an endpoint's preferred CRC 
> usage. When this
> field is '0' in the "MPA Request Frame" and the "MPA Reply 
> Frame", CRCs
> MUST not be checked and need not be generated by either endpoint. When
> this bit is '1' in either the "MPA Request Frame" or "MPA 
> Reply Frame",
> CRCs MUST be generated and checked by both endpoints.
> 
> The question:
> 
> If an MPA request frame has set the CRC bit to 1, can the MPA replay
> frame's CRC bit be set to 0 without violating the draft.
> 
> >From a strict reading of the draft there does not seem to be a
> requirement that a "1" in the request results in a "1" in the reply,
> only that both devices must use CRCs.
> 
> So is the meaning of a "0" in the reply frame "I'm not using 
> CRCs, or is
> it I didn't want to use CRCs". Further if the requester sees 
> a 0 in the
> reply frame after setting the CRC bit to 1 in the request frame should
> it reset the connection?
> 
> Barry Reinhold
> Lamprey Networks
> [email protected]
> (603) 868-8411
>  
> 
> 
> 
>