public inbox for dm-crypt@saout.de
 help / color / mirror / Atom feed
From: Arno Wagner <arno@wagner.name>
To: dm-crypt@saout.de
Subject: Re: [dm-crypt] bits vs bytes
Date: Mon, 30 Mar 2020 23:00:22 +0200	[thread overview]
Message-ID: <20200330210022.GA31903@tansi.org> (raw)
In-Reply-To: <ed117975-e332-44b4-9cc8-431f10739146@localhost>

On Mon, Mar 30, 2020 at 22:25:02 CEST, Michael Kjörling wrote:
> On 30 Mar 2020 20:03 +0000, from moreejt@yahoo.com (JT Morée):
> > When I run luksDump i see that multiple locations give sizes in
> > 'bits'.  Is that correct?   Normally, we operate in 8 bit => bytes. 
> > If I read this correctly then
> > 
> > 2: luks2 (unbound)
> >   Key:        512 bits = 64 bytes
> 
> Cryptographic key sizes, hash lengths, block sizes, and similar
> quantities are commonly stated in bits, not bytes, especially for
> algorithms typically implemented on digital, binary computers (in
> either hardware or software).
> 
> There's likely a variety of reasons for this; some historical, some
> mathematical.

Probably the most important is that the concept of a byte has no
real meaning for these values.

Regards,
Arno

-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
A good decision is based on knowledge and not on numbers. -- Plato

If it's in the news, don't worry about it.  The very definition of 
"news" is "something that hardly ever happens." -- Bruce Schneier

  reply	other threads:[~2020-03-30 21:00 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <566872408.1293730.1585598590645.ref@mail.yahoo.com>
2020-03-30 20:03 ` [dm-crypt] bits vs bytes JT Morée
2020-03-30 20:25   ` Michael Kjörling
2020-03-30 21:00     ` Arno Wagner [this message]
2020-03-30 21:18       ` JT Morée
     [not found]         ` <20200331014306.GA2009@tansi.org>
2020-03-31  5:35           ` JT Morée
2020-03-31  6:43             ` Arno Wagner
2020-03-31  6:55               ` Michael Kjörling
2020-03-31  9:32                 ` Arno Wagner
2020-03-31  7:06         ` Michael Kjörling

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200330210022.GA31903@tansi.org \
    --to=arno@wagner.name \
    --cc=dm-crypt@saout.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox