NODE 227ce8e9Re: [CyberCash Media hype]
jamiel@sybase.com (Jamie Lawrence)Thu, 15 Sep 94 15:17:41 PDT
Uh, I was paraphrasing the conclusions of the article in
order to convey that the authors clearly have no clue about
security software. I (incorrectly) thought there was sufficient
sarcasm in my post to convey that.
Question - where did the below-highlighted opinion come from?
Also, I do disagree with your statement "security through
obscurity is no security at all." A rather high degree of
security can be had through obscurity, but it is often entirely
unpredictable whether or not a particlar 'obscurity method'
will be secure or not (any 15 year old hiding cigarettes under
the bed can attest to that). I see this as an extension of the
pricipals underlying modern crypto - it could be that a factoring
attack on RSA is possible but really obscure. It is simply an
example of more predictable security through obscurity. Perhaps
I'm pushing definitions a little too far here.
At 2:45 PM 9/15/94, Chael Hall wrote:
>>
>>These are my favorite paragraphs.
>>
>>1) Proprietary == secure
>>
>>2) Understanding how it works == insecure
>
> I disagree. Proprietary is MORE secure, but security through
^^^^^^^^^^^^^^^^^^^^^^^^^^
>obscurity is no security at all. The only thing that does is separate
>the proverbial men from the boys. It keeps the idiots who think they
>can crack a system from touching it, but the people who know what they
>are doing will learn it rather quickly.
>
> Understanding how it works is also not necessarily insecure either.
>What about PGP? Would you rather use some proprietary methond that may
>or may not have a backdoor or may not be as secure as it is touted to
>be? I prefer to use something that has been proven and tested.
>
>Chael
-j
--
"It's a question of semantics, and I've always been rather anti-
semantic." -Gene Simmons
___________________________________________________________________
Jamie Lawrence <foodie@netcom.com> <jamiel@sybase.com>
NODE fcf86128Re: [CyberCash Media hype]
"Ian Farquhar" <ianf@wiley.sydney.sgi.com>Sun, 18 Sep 94 21:17:23 PDT
On Sep 15, 3:20pm, Jamie Lawrence wrote:
> Also, I do disagree with your statement "security through
> obscurity is no security at all." A rather high degree of
> security can be had through obscurity, but it is often entirely
> unpredictable whether or not a particlar 'obscurity method'
> will be secure or not (any 15 year old hiding cigarettes under
> the bed can attest to that).
This is absolutely correct. Keeping your secret key a secret _is_
security by obscurity, although in a much wider context than most people
would use the term. In addition, it is also particularly effect if what
is being obscured is sufficiently secure already, as it just adds another
layer of protection.
For example, if I decided to superencrypt using some publicly known
and reasonably trusted ciphers (let's say DES, LOKI and IDEA), and decided
to keep the algorithms I had used and the order I had used them a secret,
I have _not_ decreased my security. The obscurity does not deduct from
the security of these already moderately trusted ciphers, and the work
which would have to be added to figure out what I have done increases it
(although by an amount which is probably arguable).
I am sure that this is a point almost everyone here understands this
concept, but it's amazing how many times the argument "it's a secret,
therefore it's insecure" comes out. It's only really insecure if the
thing you're keeping a secret is, and even then you have not decreased
it's effective security by obscuring it.
The TLA's understand this concept well, which is one of the reasons they
classify almost everything they do. One non-obvious fact is that in the
environment most governments use crypto (eg. widely distributed sites with
key distribution channels which are more easily compromised than the
crypto hardware), that the design of the cipher may be easier to keep
secret than the key itself. As such, the use of security by obscurity
in the design of the cipher itself is a lot more effective than most
people would give it credit for.
Ian.
NODE 3e29b9cdRe: [CyberCash Media hype]
Black Unicorn <unicorn@access.digex.net>Mon, 19 Sep 94 14:36:47 PDT
Ian Farquhar scripsit
>
> On Sep 15, 3:20pm, Jamie Lawrence wrote:
> > Also, I do disagree with your statement "security through
> > obscurity is no security at all." A rather high degree of
> > security can be had through obscurity, but it is often entirely
> > unpredictable whether or not a particlar 'obscurity method'
> > will be secure or not (any 15 year old hiding cigarettes under
> > the bed can attest to that).
I prefer: "security through obscurity ALONE is no security at all."
> In addition, it is also particularly effect if what
> is being obscured is sufficiently secure already, as it just adds another
> layer of protection.
Guess I'm not the only one.
>
> The TLA's understand this concept well, which is one of the reasons they
> classify almost everything they do. One non-obvious fact is that in the
> environment most governments use crypto (eg. widely distributed sites with
> key distribution channels which are more easily compromised than the
> crypto hardware), that the design of the cipher may be easier to keep
> secret than the key itself. As such, the use of security by obscurity
> in the design of the cipher itself is a lot more effective than most
> people would give it credit for.
>
While this may seem to be a joke comment, it is not.
They also classify just about if not exactly everything because it never
will be looked at seriously by the policy makers if it's not marked at
least "secret."
The major hurtle in intelligence is often not collection or analysis, but
persuasion.
> Ian.
-uni- (Dark)
--
073BB885A786F666 nemo repente fuit turpissimus - potestas scientiae in usu est
6E6D4506F6EDBC17 quaere verum ad infinitum, loquitur sub rosa - wichtig!
NODE cb8ec00cRe: [CyberCash Media hype]
"Ian Farquhar" <ianf@wiley.sydney.sgi.com>Tue, 20 Sep 94 17:38:19 PDT
On Sep 19, 5:35pm, Black Unicorn wrote:
> > The TLA's understand this concept well, which is one of the reasons they
> > classify almost everything they do. One non-obvious fact is that in the
> > environment most governments use crypto (eg. widely distributed sites with
> > key distribution channels which are more easily compromised than the
> > crypto hardware), that the design of the cipher may be easier to keep
> > secret than the key itself. As such, the use of security by obscurity
> > in the design of the cipher itself is a lot more effective than most
> > people would give it credit for.
> While this may seem to be a joke comment, it is not.
Remember that what is being secured here is almost certainly a stronger
cipher than any of us have access to (representatives of TLA's excepted :),
and so the public scrutiny issue does not arise.
I agree with Black Unicorn's phrase: security by obscurity alone is no
security. If we need a buzzphrase - which itself is questionable - then
that's about a close as we'll get.
Ian.
NODE 1c84d0efSecurity through obscurity
Adam Shostack <adam@bwh.harvard.edu>Wed, 21 Sep 94 07:48:10 PDT
Ian Farquhar wrote:
| > > crypto hardware), that the design of the cipher may be easier to keep
| > > secret than the key itself. As such, the use of security by obscurity
| > > in the design of the cipher itself is a lot more effective than most
| > > people would give it credit for.
|
| > While this may seem to be a joke comment, it is not.
|
| Remember that what is being secured here is almost certainly a stronger
| cipher than any of us have access to (representatives of TLA's excepted :),
| and so the public scrutiny issue does not arise.
| I agree with Black Unicorn's phrase: security by obscurity alone is no
| security. If we need a buzzphrase - which itself is questionable - then
| that's about a close as we'll get.
Obscuring things can be a useful part of a security system for
an organization. The phrase "security through obscurity" refers to
systems which are all smoke and mirrors. Good security comes from
reinforced concrete. If you add smoke and mirrors in front of
concrete, you don't decrease your security. Unless, of course, you
can't see whats coming becuse of all the smoke.
Adam
NODE 3bcc4545Re: [CyberCash Media hype]
Phil Karn <karn@qualcomm.com>Mon, 19 Sep 94 20:05:16 PDT
Perhaps the saying "security through obscurity doesn't work" should be
amended to say "security that depends on the secrecy of anything that
cannot be easily changed doesn't work".
In most cases, cryptographic keys are far more easily changed than
cryptographic algorithms. That's why it's bad to rely on the secrecy
of an algorithm, but okay to rely on the secrecy of a key.
Phil