NODE 65ec369cSound card as a random number source ??
Pavel Korensky <pavelk@dator3.anet.cz>Wed, 27 Nov 1996 07:28:57 -0800 (PST)
Hello,
when I read about hardware random number generators in this mailing list, I got
one idea. Maybe it sounds crazy, but is it possible to use soundcard
(SoundBlaster for example) as a source for really random numbers ?
What if I connect the input line of the soundcard with some external source of
noise, like FM receiver or Dolby Surround decoder (with built-in white noise
generator) or tape recorder with blank (erased) tape. It is possible to sample
the sound (noise) and use the sampled values as a random numbers ? And how much
random is this source ?
I tried to find some mentions about this method with altavista, but I didn't
found anything.
Bye PavelK
--
****************************************************************************
* Pavel Korensky (pavelk@dator3.anet.cz) *
* DATOR3 Ltd., Modranska 1895/17, 143 00 Prague 4, Czech Republic *
* PGP key fingerprint: 00 65 5A B3 70 20 F1 54 D3 B3 E4 3E F8 A3 5E 7C *
****************************************************************************
NODE b02f3e8bRe: Sound card as a random number source ??
"Mark M." <markm@voicenet.com>Wed, 27 Nov 1996 11:23:41 -0800 (PST)
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On Wed, 27 Nov 1996, Pavel Korensky wrote:
> when I read about hardware random number generators in this mailing list, I got
> one idea. Maybe it sounds crazy, but is it possible to use soundcard
> (SoundBlaster for example) as a source for really random numbers ?
> What if I connect the input line of the soundcard with some external source of
> noise, like FM receiver or Dolby Surround decoder (with built-in white noise
> generator) or tape recorder with blank (erased) tape. It is possible to sample
> the sound (noise) and use the sampled values as a random numbers ? And how much
> random is this source ?
The LSBs of a recording of white noise or static should be pretty random.
This should not be your only source of entropy as it's very easy for an
attacker to bias the signals. If a one-way hash is applied to the output, it
does make it much more difficult for an attacker to predict or influence the
RNG.
Mark
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NODE 702d2d24Re: Sound card as a random number source ??
Adam Shostack <adam@homeport.org>Wed, 27 Nov 1996 12:57:10 -0800 (PST)
Have you tried it without a mike plugged in?
Always think about failure modes.
Adam
Pavel Korensky wrote:
| Hello,
|
| when I read about hardware random number generators in this mailing list, I got
| one idea. Maybe it sounds crazy, but is it possible to use soundcard
| (SoundBlaster for example) as a source for really random numbers ?
| What if I connect the input line of the soundcard with some external source of
| noise, like FM receiver or Dolby Surround decoder (with built-in white noise
| generator) or tape recorder with blank (erased) tape. It is possible to sample
| the sound (noise) and use the sampled values as a random numbers ? And how much
| random is this source ?
| I tried to find some mentions about this method with altavista, but I didn't
| found anything.
|
| Bye PavelK
|
|
| --
| ****************************************************************************
| * Pavel Korensky (pavelk@dator3.anet.cz) *
| * DATOR3 Ltd., Modranska 1895/17, 143 00 Prague 4, Czech Republic *
| * PGP key fingerprint: 00 65 5A B3 70 20 F1 54 D3 B3 E4 3E F8 A3 5E 7C *
| ****************************************************************************
|
--
"It is seldom that liberty of any kind is lost all at once."
-Hume
NODE ebdf9694Re[2]: Sound card as a random number source ??
Pavel Korensky <pavelk@dator3.anet.cz>Thu, 28 Nov 1996 03:25:30 -0800 (PST)
Adam Shostack <adam@homeport.org> wrote:
> Have you tried it without a mike plugged in?
> Always think about failure modes.
>
> Adam
>
But there always can be some kind of test, like presampling and testing if the
input is not dead.
And of course some kind of hash algorithm must be applied to the sampled stream
(MD5 ?).
Bye PavelK
--
****************************************************************************
* Pavel Korensky (pavelk@dator3.anet.cz) *
* DATOR3 Ltd., Modranska 1895/17, 143 00 Prague 4, Czech Republic *
* PGP key fingerprint: 00 65 5A B3 70 20 F1 54 D3 B3 E4 3E F8 A3 5E 7C *
****************************************************************************
NODE 13a3693eRe: Sound card as a random number source ??
The Deviant <deviant@pooh-corner.com>Wed, 27 Nov 1996 18:43:14 -0800 (PST)
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On Wed, 27 Nov 1996, Adam Shostack wrote:
> Have you tried it without a mike plugged in?
> Always think about failure modes.
>
> Adam
>
>
> Pavel Korensky wrote:
> | Hello,
> |
> | when I read about hardware random number generators in this mailing list, I got
> | one idea. Maybe it sounds crazy, but is it possible to use soundcard
> | (SoundBlaster for example) as a source for really random numbers ?
> | What if I connect the input line of the soundcard with some external source of
> | noise, like FM receiver or Dolby Surround decoder (with built-in white noise
> | generator) or tape recorder with blank (erased) tape. It is possible to sample
> | the sound (noise) and use the sampled values as a random numbers ? And how much
> | random is this source ?
> | I tried to find some mentions about this method with altavista, but I didn't
> | found anything.
> |
> | Bye PavelK
> |
Also, try reading from the PC speaker (this is usually a device on the
sound card) without the speaker as input... the leads usually make enough
of an antena to get all of your hardwares RF emissions, which should be
a good source of random numbers.
--Deviant
PGP KeyID = E820F015 Fingerprint = 3D6AAB628E3DFAA9 F7D35736ABC56D39
The best way to accelerate a Macintoy is at 9.8 meters per second per second.
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