Re: [dtn-security] Re: [dtn-dev] Re: SDNV-new

Scott Burleigh <Scott.Burleigh@jpl.nasa.gov> Thu, 26 May 2005 19:10 UTC

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Date: Thu, 26 May 2005 12:09:05 -0700
From: Scott Burleigh <Scott.Burleigh@jpl.nasa.gov>
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Subject: Re: [dtn-security] Re: [dtn-dev] Re: SDNV-new
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Michael Demmer wrote:

>>I don't much care one way or another.  Do we really think we're
>>likely to need to represent numbers bigger than (2*68) - 1 in SDNVs?
>>    
>>
>
>Very doubtful if all they're used for is lengths, maybe so if they're
>used for other things like crypto keys and such.
>
If we think we really are going to use SDNVs for crypto keys then I 
think 1/2/3/4/6/8/12/16 isn't going to be enough, because crypto keys 
only seem to get longer as the years go by.  I think that would argue 
for either the original SDNV-8 (or -16) scheme or else an encoding along 
the lines of 1/2/4/8/16/32/64/128.

If not -- that is, if we're going use ordinary LV structures (an 8-bit 
length followed by that many bytes of content) for encryption keys -- 
then I don't see any point in moving away from 1/2/3/4/5/6/7/8.

Scott