Re: [apps-discuss] SenML

Yusuke DOI <yusuke.doi@toshiba.co.jp> Fri, 09 March 2012 17:43 UTC

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Date: Sat, 10 Mar 2012 02:43:38 +0900
From: Yusuke DOI <yusuke.doi@toshiba.co.jp>
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To: "Kaebisch, Sebastian" <sebastian.kaebisch.ext@siemens.com>
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Subject: Re: [apps-discuss] SenML
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Dear Kaebisch,

I have several comments.


(2012/03/10 0:05), Kaebisch, Sebastian wrote:

> 2) instead of using a "float" value, I would recommend to use the "mantissa" and "exponend" representation. A floating value is always a challenge for constrained devices because of its inefficent processing.

I think float values in EXI is already mantissa and exponend (base 10).

> 3) use restriction definitions of strings (define maxLength or list all possible values as enumeration). Especially using enumerations results in a smaller message size and avoids string comparison.

Enumeration is good idea but I think strict enumeration allows no 
addition in future without breaking backword compatibility. I recommend 
some 'dummy entries' to make room (and show the limit to keep the same 
bitwidth clearly) for future.

Yusuke