Re: [Ntp] draft-ietf-ntp-roughtime-05: tag change makes implementation more complex

JP Sugarbroad <taralx@gmail.com> Tue, 21 September 2021 03:32 UTC

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From: JP Sugarbroad <taralx@gmail.com>
Date: Mon, 20 Sep 2021 20:31:51 -0700
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To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [Ntp] draft-ietf-ntp-roughtime-05: tag change makes implementation more complex
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Isn't the requirement to have tags in order?

On Mon, Sep 20, 2021, 19:56 Watson Ladd <watsonbladd@gmail.com> wrote:

> On Sun, Sep 19, 2021 at 12:22 PM JP Sugarbroad <taralx@gmail.com> wrote:
> >
> > In the pre-ietf draft, short tags were padded with FF, putting them at
> the end of the tag sequence. Now they're padded with 00, which puts them at
> the start. So packets start with PAD rather than ending with it, noticeably
> complicating packet construction.
>
> Dear JP,
>
> I don't think this complicates packet construction much. If you know
> the length of all elements ahead of time, and then compute the PAD,
> nothing changes. If you are accumulating elements and putting PAD at
> the end after knowing the length, it's a little bit of buffer
> manipulation.
>
> Sincerely,
> Watson Ladd
>
> >
> > --
> > JP Sugarbroad <taralx@gmail.com>
> > "Please let me know if there's any further trouble I can give you."
> >     -- Unknown
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>
>
> --
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>