Page 36 of draft 07 or RDMAP states that:

HdrCt: 3 bits.

Header control bits:

* M: bit 16. DDP Segment Length valid. See Figure 10 for when this bit SHOULD be set.

* D: bit 17. DDP Header Included. See Figure 10 for when this bit SHOULD be set.

* R: bit 18. RDMAP Header Included. See Figure 10 for when this bit SHOULD be set.

The SHOULD statements in this text indicate that these items are optional. However, in reading the text it appears that the intent may have been that these statements are just incorrectly capitalized “should” statements and best understood as:

HdrCt: 3 bits.

Header control bits:

* M: bit 16. DDP Segment Length valid. See Figure 10 for when to set this bit.

* D: bit 17. DDP Header Included. See Figure 10 for when to set this bit.

* R: bit 18. RDMAP Header Included. See Figure 10 for when to set this bit.

The implication of this would be, for instance, that an implementation MUST set the R bit and return the received RDMA header when generating a terminate for a read request that generated a remote protection error due to an invalid Stag.

A literal reading of the current wording (with SHOULD) leaves a somewhat conflicted state in which figure 10 states that the RDMA header is required but that it is not necessary to set the R bit.

Unless instructed otherwise I am going to assume that the SHOULD in HdrCt is not really normative.

Hope someone is still reading this reflector….

Barry Reinhold

(603) 868-8411

bbr <at> lampreynetworks.com

DDP and RDMAP appear to provide conflicting information as to whether or not a DDP header is required when DDP detects an invalid STAG.

Draft 07 of DDP in clause 7.1 states:

If the DDP layer detects any of the receive errors listed in this

section, it MUST cease placing the remainder of the DDP Segment and

report the error(s) to the ULP. The DDP layer SHOULD include in the

error report the DDP Header, the type of error, and the length of

the DDP segment, if available.  

Draft 07 or RDMAP in figure 10 for a DDP error places a “YES” in the column that identifies the DDP header as being required.

The question is  “Does she or doesn’t she”…. Have to provide the DDP header?

Barry Reinhold

(603) 868-8411

bbr <at> lampreynetworks.com

DDP and RDMAP appear to provide conflicting information as to whether or not a DDP header is required when DDP detects an invalid STAG.

Draft 07 of DDP in clause 7.1 states:

If the DDP layer detects any of the receive errors listed in this

section, it MUST cease placing the remainder of the DDP Segment and

report the error(s) to the ULP. The DDP layer SHOULD include in the

error report the DDP Header, the type of error, and the length of

the DDP segment, if available.  

Draft 07 or RDMAP in figure 10 for a DDP error places a “YES” in the column that identifies the DDP header as being required.

The question is  “Does she or doesn’t she”…. Have to provide the DDP header?

Barry Reinhold

(603) 868-8411

bbr <at> lampreynetworks.com