Re: [6lo] Last Call: <draft-ietf-6lo-deadline-time-03.txt> (Packet Delivery Deadline time in 6LoWPAN Routing Header) to Proposed Standard

[Tal Mizrahi <[e-mail]>]

Hi Suresh, authors,

>> I would suggest to follow the timestamp specification template of
Section
>> 3 in draft-ietf-ntp-packet-timestamps-05.

>I think the semantics of the DT and OT fields are a bit different from the
>NTP packet timestamps and there are also resource constraints in the
>6lo world that might make the 64 bit formats expensive. I will let the
>authors and the WG comment further on this.


I agree that the NTP timestamp format does not fit here.
My comment was that DT and OT should be defined according to the timestamp
specification template (section 3 in the packet timestamp draft).
This is a *generic template* for defining all kinds of timestamp formats.
The template was defined in order to make sure that when you define a
timestamp format you do not forget important details.
Just to clarify, I am not suggesting to change the timestamp formats of DT
and OT, but only to specify them in a clear and unambiguous manner.

Thanks,
Tal.




On Wed, Jan 2, 2019 at 11:00 PM Suresh Krishnan <[e-mail]> wrote:

> Hi Tal,
>
> On Dec 23, 2018, at 3:49 AM, Tal Mizrahi <[e-mail]>
> wrote:
>
> Hi,
>
> I am not a 6lo native, but I reviewed the draft specifically from a
> timestamp formatting perspective.
> In the NTP working group we currently have a draft in WGLC that presents
> guidelines for defining timestamp formats.
> https://tools.ietf.org/html/draft-ietf-ntp-packet-timestamps-05
>
> I believe that the definitions of the timestamps (DT and OT)
> in draft-ietf-6lo-deadline-time should be more detailed. For example,
> aspects about the epoch and the potential effect of leap seconds are
> currently not described in the current draft.
>
>
> Good point. Authors, can you add some further descriptive text around
> these fields.
>
> I would suggest to follow the timestamp specification template of Section
> 3 in draft-ietf-ntp-packet-timestamps-05.
>
>
> I think the semantics of the DT and OT fields are a bit different from the
> NTP packet timestamps and there are also resource constraints in the 6lo
> world that might make the 64 bit formats expensive. I will let the authors
> and the WG comment further on this.
>
> Thanks
> Suresh
>
>