nanog mailing list archives

Re: best way to create entropy?


From: shawn wilson <ag4ve.us () gmail com>
Date: Fri, 12 Oct 2012 01:04:49 +0000

On Fri, Oct 12, 2012 at 12:49 AM, Robert M. Enger <NANOG () enger us> wrote:
On 10/11/2012 5:08 PM, Jonathan Lassoff wrote:

On Thu, Oct 11, 2012 at 5:01 PM, shawn wilson <ag4ve.us () gmail com> wrote:

in the past, i've done many different things to create entropy -
encode videos, watch youtube, tcpdump -vvv > /dev/null, compiled a
kernel. but, what is best? just whatever gets your cpu to peak or are
some tasks better than others?

Personally, I've used and recommend this USB stick:
http://www.entropykey.co.uk/

Internally, it uses diodes that are reverse-biased just ever so close
to the breakdown voltage such that they randomly flip state back and
forth.

Cheers,
jof

Intel claims to include a hardware Digital Random Number Generator (DRNG) in
its later generation chips.  Is their offering inadequate/discredited?

http://en.wikipedia.org/wiki/RdRand
http://www.pcmag.com/article2/0,2817,2391367,00.asp
http://www.intel.com/p/en_US/embedded/innovation/security/walker-article-security
http://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide/


that's good to know about. i'll have to remember it when tech moves
along in a year or so. but, right now, i don't think i have that
capability. also, i'd prefer to have a chip agnostic solution as a
month or so ago, i wanted to create a key on a raspberry pi (should've
just copied one over) and it took forever to generate enough entropy -
even as i was compiling stuff. after that, i considered tcpdump.


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