Re: [trill] Alissa Cooper's Discuss on draft-ietf-trill-smart-endnodes-10: (withDISCUSS and COMMENT)

[Donald Eastlake <[e-mail]>]

On Wed, Mar 7, 2018 at 10:01 AM, Alissa Cooper <[e-mail]> wrote:
> Hi Fangwei,
>
> As I noted in response to the Gen-ART reviewer, I managed to ballot before
> reading the rest of this thread (sorry!), but I still think the diagram in
> 4.3 is confusing and not consistent with the text. To my eye row 3 shows
two
> bytes’ worth of fields but the label says “4 bytes.” RSV is depicted as 2
> bits but the text says it is 6 bits. The combination of these two
> inconsistencies makes it hard to know what the actual lengths are supposed
> to be.

I agree that the figure is a little confusing. I suggest the following:

    +-+-+-+-+-+-+-+-+
    |Type=Smart-MAC |          (1 byte)
    +-+-+-+-+-+-+-+-+
    |   Length      |          (1 byte)
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+
    |F|M|  RSV      |  VLAN/FGL Data Label         |  (4 bytes)
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                          MAC (1)                (6 bytes)        |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                      .................                           |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                          MAC (N)                (6 bytes)        |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Thanks,
Donald
===============================
 Donald E. Eastlake 3rd   [phone] (cell)
 155 Beaver Street, Milford, MA 01757 USA
 [e-mail]

> Alissa
>
> On Mar 7, 2018, at 12:55 AM, [e-mail] wrote:
>
> Hi，Alissa Cooper
>
> Thanks for your review and comments.
>
> The new version(version 10)  has updated to fix your comments.
>
> The format of Smart-MAC APP sub-TLV and the text  has been changed to the
> following:
>
> The length of F,M,RSV,VLAN/FGL data Label is 4 bytes. and the length of
> VLAN/FGL Data Label field is 24 bits.
>
>
>    +-+-+-+-+-+-+-+-+
>     |Type=Smart-MAC |                  (1 byte)
>     +-+-+-+-+-+-+-+-+
>     |   Length      |                  (1 byte)
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |F|M|RSV|  VLAN/FGL Data Label  |  (4 bytes)
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |                          MAC (1)       (6 bytes)                 |
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |                      .................                           |
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>     |                          MAC (N)       (6 bytes)                 |
>     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-...+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>
>                      Figure 3 Smart-MAC APPsub-TLV
>
>
>    o  VLAN/FGL Data Label: 24bits.  If F is 1, this field is a 24-bit
>       FGL Data Label for all subsequent MAC addresses in this APPsub-
>       TLV.  Otherwise, if F is 0, the lower 12 bits is the VLAN of all
>       subsequent MAC addresses in this APPsub-TLV, and the upper 12 bits
>       is not used(sent as zero and ignored on receipt).  If there is no
>       VLAN/FGL data label specified, the VLAN/FGL Data Label is zero.
>
>
>
>
> Regards.
>
> Fangwei.
>
> 原始邮件
> 发件人：AlissaCooper <[e-mail]>
> 收件人：The IESG <[e-mail]>
> 抄送人：[e-mail]
> <[e-mail]>[e-mail]
> <[e-mail]>[e-mail] <[e-mail]>[e-mail]
> <[e-mail]>
> 日 期 ：2018年03月07日 04:45
> 主 题 ：Alissa Cooper's Discuss on draft-ietf-trill-smart-endnodes-10:
> (withDISCUSS and COMMENT)
> Alissa Cooper has entered the following ballot position for
> draft-ietf-trill-smart-endnodes-10: Discuss
>
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>
>
> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
> for more information about IESG DISCUSS and COMMENT positions.
>
>
> The document, along with other ballot positions, can be found here:
> https://datatracker.ietf.org/doc/draft-ietf-trill-smart-endnodes/
>
>
>
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
>
> This should hopefully be easy to fix and was pointed out by the Gen-ART
> reviewer:
>
> All of section 4.3 is confusing as to what the length of the TLV really
is.
> Row 3 in the diagram says 2 bytes or 4 bytes, but the number of bits
called
> out
> in bullets 4 and 5 below it don't seem to add up to those things. Maybe it
> would
> be better to draw a diagram with F=0 and a separate diagram with F=1.
>
> Please make it clear both in the diagram and in the text what the expected
> lengths of the fields are -- I find it particularly confusing that the
> number
> of bits pictured doesn't align with the number of bits specified in the
text
> per field.
>
>
> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
>
> Please also look at the Gen-ART reviewer's other comments.
>
>
>