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

Watson Ladd <watsonbladd@gmail.com> Tue, 21 September 2021 02:56 UTC

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From: Watson Ladd <watsonbladd@gmail.com>
Date: Mon, 20 Sep 2021 19:56:02 -0700
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To: JP Sugarbroad <taralx@gmail.com>
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Subject: Re: [Ntp] draft-ietf-ntp-roughtime-05: tag change makes implementation more complex
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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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