Re: [Roll] regarding DIS Modifications draft (draft-goyal-roll-dis-modifications-00)

Emmanuel Baccelli <Emmanuel.Baccelli@inria.fr> Mon, 14 November 2011 02:08 UTC

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From: Emmanuel Baccelli <Emmanuel.Baccelli@inria.fr>
Date: Mon, 14 Nov 2011 02:59:53 +0100
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Subject: Re: [Roll] regarding DIS Modifications draft (draft-goyal-roll-dis-modifications-00)
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Hi Yoav,
good call. In fact the current specification interprets the randomization
range being from 0 to 2^SpreadingInterval ms. The maximum interval is thus
 0 to 2^256 ms, which is quite an astronomic number already! Do you think
we need some more fancy way to define the range from the number specified
in the SpreadingInterval field?
Cheers
Emmanuel


On Sun, Nov 13, 2011 at 5:32 PM, Yoav Ben-Yehezkel <yoav@yitran.com> wrote:

> Hi,
>
>
>
> I went through the draft, it seems interesting.
>
>
>
> I had one concern regarding the use of the Response Spreading Option
> specified in 4.2.
>
>
>
> 8 bits specified in ms can be a too small randomization for some L2
> technologies (such as narrowband powerline).
>
>
>
> Would it be possible to increase the number of bits (although 16 seems
> like an overkill)?
>
> Another option could be to divide the field into two (first part units:
> ms, 10ms, 100ms, etc. and second part randomization range)?
>
>
>
> I expect that in order to avoid collisions this randomization is best
> achieved if the units are at the magnitude of the duration of a frame or so.
>
>
>
> Best regards,
>
> Yoav
>
>
>
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