Cryptography-Digest Digest #713, Volume #12 Tue, 19 Sep 00 00:13:00 EDT
Contents:
New BUGS Contest, should be much easier ! (Sylvain Martinez)
Re: Chosen and known attacks - are they possible ?? (Bryan Olson)
Re: "Secrets and Lies" at 50% off (R��)
Re: Dangers of using same public key for encryption and signatures? (Bryan Olson)
Re: Dangers of using same public key for encryption and signatures? (Bryan Olson)
Re: A conjecture - thoughts? (Matthew Skala)
Re: One-way encryption ("Thanh Diep")
Re: ExCSS Source Code (David A. Wagner)
Re: A conjecture - thoughts? (David Hopwood)
Re: Q: Crypto-PC (David Hopwood)
Re: Assistance ("P.C. Teo")
Re: ExCSS Source Code (Bill Unruh)
Re: Software patents are evil. (Bill Unruh)
Re: Algebra, or are all block ciphers in trouble? (Mack)
Re: Hamming weight (Mack)
Re: CDMA tracking (was Re: GSM tracking) (Mack)
Re: Software patents are evil. ("Dann Corbit")
----------------------------------------------------------------------------
From: Sylvain Martinez <[EMAIL PROTECTED]>
Subject: New BUGS Contest, should be much easier !
Date: Tue, 19 Sep 2000 01:02:03 GMT
Hi,
After what some of you said yesterday I've changed my previous contest.
You know have 2 ciphers texts crypted with the same key AND the 2 clear
texts, the source code of the algorithm, loads of documentation.
If after all that nobody can find the key used tocrypt those files,
this algorithm might no be so bad after all...
Here is the new contest:
BUGS CONTEST #2
Prize : 50 English pounds
Start of the contest: 19 September 2000
End of the contest : 19 September 2001
To test the strenght of this algorithm, I've decided to run a contest.
Because this is a free software and I created it during my free time,
I can't offer a lot of money. However I hope that this will push more
people to try to crack my algorithm.
This new BUGS contest cancelled the previous BUGS contest from the 01
August 2000
The 2 ciphers texts are the same than for the previous contest.
RULES
Information given:
2 cipher texts which have been crypted with the same KEY
the 2 original clear texts
The size of the key used: 256 bits
Each clear text have been crypted using different parameters values
(block shuffle/block crypt)
FILE TO DOWNLOAD: http://www.bcrypt.com/crypto/bugscontest.zip
More information on: http://www.bcrypt.com
In order to win and claim your prize, you need to:
(me = Sylvain Martinez)
Find the key and the parameters used to crypt the 2 clear texts.
Send me a report explaining how you did it
Send me the source of your application which found the key and
parameters
Your key has to be the same than the one I used to crypt the files
You need to send me your answer before the 19 September 2001
In the event that many people send me a solution to find the key, then
the quickest and most generic application will win.
Pleople who sent me a solution will have their name listed on the web
site: http://www.bcrypt.com and their application available only if
they want it to be (as it might give hints for other competitors)
The winner will be annonced after the 19th of september 2001 (within a
week)
If nobody can crack my algorithm and find the key/parameters, the
solution will be posted on the Web Site: http://www.bcrypt.com after
the 19th September 2001
--
---
Unix security administrator
BUGS crypto project: http://www.bcrypt.com
http://www.encryptsolutions.com
Sent via Deja.com http://www.deja.com/
Before you buy.
------------------------------
From: Bryan Olson <[EMAIL PROTECTED]>
Subject: Re: Chosen and known attacks - are they possible ??
Date: Tue, 19 Sep 2000 01:07:52 GMT
"kihdip" asked:
> The models are frequently used to describe an attack form:
> - Ciphertext only
> - Known plaintext
> - Chosen plaintext
> - Chosen ciphertext
>
> Forgive my ignorance, but are the known and chosen attacks
> only teoretical ?? If not: How would an attacker get a
> chosen plaintext encrypted ?? (His goal is to find the key,
> so obviously he cannot encrypt the plaintext himself)
Even the most theoretical-sounding actually happens.
Consider a subscription satellite-TV service. The content
is sent encrypted, and each subscriber has a
tamper-resistant box that decrypts it. Now suppose a pirate
wants to make working decryption devices. He can subscribe
to get a box, then introduce his own data and see what comes
out - the chosen ciphertext attack.
--Bryan
--
email: bolson at certicom dot com
Sent via Deja.com http://www.deja.com/
Before you buy.
------------------------------
From: R�� <pctech@wlsm�il.com>
Crossposted-To: comp.security,comp.security.misc
Subject: Re: "Secrets and Lies" at 50% off
Date: Tue, 19 Sep 2000 01:28:38 GMT
This appears to be a discussion that has run its course, and that makes
me reticent to respond after such a timeframe. ON the other hand, I
also believe that it is a VERY important subject that affects all of
Usenet. I am NOT going to be insulted by being ignored.
But... exactly WHAT is the purpose of this group? I don't have the FAQ
close at hand, and I'm new enough that I may not even have reached any
posts that refer to it as yet. But it's that very purpose that is at
the core of what I feel is truly relevant material and what is not.
I cannot argue that a book written by an authority so recognized as you
all make clear is not of interest to those in this group. Just as posts
about WindowsNT books are of interest to readers of the MCSE
certification newsgroups. But I bring up those groups for the very
reason that just such posts(and the lack of action against them) are
being used as justification by real spammers hawking their materials for
auction on EBay or available on their own sites. These spammers are
posting about materials that could easily be argued to be of interest,
but that is ALL they do. And as a defense, they point to recognized
authorities being allowed such commercial posts.
I don't like what such posts have done to the time it takes me to read
through the groups in question, and the cost that induces in the kind of
"signal-to-noise" ratio thus resulting. I have to grant that the
"comp" hierarchy of newsgroups don't have the same kinds of allowances
for these kinds of people that they enjoy over in the "alt" hierarchy.
Nevertheless, I think it bears thought. ARE such commercial posts, even
relevant and authoritative ones, worth the trouble they may one day
allow in? If Bruce Schneier is acceptable in hawking his book, then why
not FatBrain itself? And if not FatBrain, then is Bruce's *publisher*
permitted to speak of that same deal(assuming they're even interested in
letting you know)? And if FatBrain *is* permissible, then why not Joe
Shmoe hawking it on EBay(along with 3700 other such odds and ends)?
I'm not sure where you draw the line, so I choose to draw it at the very
beginning. Post the introduction to a chapter, then list the offer. At
least in doing that(even when it's redundant to previous posts), a topic
for discussion is brought forth along with the relevant commercial
information. And if discussion of the topics themselves(as opposed to
literature about them) really *is* the primary purpose of this group,
then I think it's worth the nitpicking to enforce it.
In article <8prii3$sla$[EMAIL PROTECTED]>, [EMAIL PROTECTED] says...
> In article <[EMAIL PROTECTED]>,
> Bruce Schneier <[EMAIL PROTECTED]> wrote:
> > This is the cheapest I've seen the book. I know what the publisher
> > sells the book for, and FatBrain is losing money on every sale. I
> > have no idea if this is a temporary promotion, or how long it will
> > last. But I figured I should get the word out:
> >
> > http://www1.fatbrain.com/asp/bookinfo/bookinfo.asp?theisbn=0471253111
>
> I know you are well intentioned but for the same reason I don't like
> other spammers, I would suggest that you don't do this.
>
> If you want to talk about your book by all means go ahead, but you
> really are spamming this group.
>
> Just my two cents, and seriously no offence intended.
>
> Tom
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
>
------------------------------
From: Bryan Olson <[EMAIL PROTECTED]>
Subject: Re: Dangers of using same public key for encryption and signatures?
Date: Tue, 19 Sep 2000 01:32:38 GMT
Brian Gladman wrote:
> In the UK keys used for signature only are not subject to
> Government Access to Keys (GAK). But keys that perform
> both signature and encryption functions can be seized under
> warrant by a number of UK authorities. And there is no
> requirement that you need to be under suspicion in order
> for keys to be seized.
Tricky. The holders of the *public* key ultimately decide
whether it performs encryption. For all the popular PK
signature schemes there's a PK encryption method that uses
the same key pair. (I'm saying "popular" to rule out things
like Merkle one-time signatures.)
How does the law handle the case of Bob releasing his public
key saying "signatures only", but Alice sending him messages
encrypted with it anyway?
--Bryan
--
email: bolson at certicom dot com
Sent via Deja.com http://www.deja.com/
Before you buy.
------------------------------
From: Bryan Olson <[EMAIL PROTECTED]>
Subject: Re: Dangers of using same public key for encryption and signatures?
Date: Tue, 19 Sep 2000 01:40:08 GMT
Mike Rosing wrote:
> You are giving up more plaintext-ciphertext pairs with the same key.
> Shouldn't be a problem as long as you change keys before you get out
> more than 2^(n/8) messages. (or 1/8th large prime factor of your curve
> order).
Can't an attacker generate all the plaintext-ciphertext
pairs he wants anyway?
--Bryan
--
email: bolson at certicom dot com
Sent via Deja.com http://www.deja.com/
Before you buy.
------------------------------
From: [EMAIL PROTECTED] (Matthew Skala)
Subject: Re: A conjecture - thoughts?
Date: 18 Sep 2000 18:50:26 -0700
In article <[EMAIL PROTECTED]>,
Andru Luvisi <[EMAIL PROTECTED]> wrote:
>I have the following conjecture:
>
>If f() and g() commute, that is f(g(x)) = g(f(x)) for all x, then
>f() and g() are both powers of some base function, b^y(x_0, x),
>where x_0 and x are the same the first time through, x_0 stays the
>same on every itteration, and the output is fed back into x.
>
>I have been able to find base functions for every pair f() and g() I
>can think of, even arbitrary sboxes which I have designed that
>commute.
The conjecture is false. Here are two 2x2 S-boxes that form a
counterexample:
f: g:
in out in out
00 01 00 00
01 00 01 01
10 10 10 11
11 11 11 10
Observe that f just swaps the values 00 and 01 and g swaps 10 and 11; if
you take f(g(x)) or g(f(x)) you'll be swapping both pairs and get the same
result either way; in other words, f and g are two bijective functions
that commute.
But you cannot get both f and g by iterating some bijective function b
(the same b for both of them) that is also from two-bit inputs onto
two-bit outputs. There are only 24 such functions and it doesn't take
long to check them all. Note that b would have to be bijective or else it
could never form f or g at all.
If you know a little more algebra, you don't even need to check the
possibilities. Observe that "bijective 2x2 S-boxes" are the same thing as
"permutations on 4 things" and that permutations are classed as "even" or
"odd"; the product of two even permutations is even, and f and g are both
odd, so b must be odd else it could never generate f and g. There are
equal numbers of odd and even permutations, so that cuts the list in half:
b must be one of the twelve permutations of four things expressible as a
product of an odd number of pairwise swaps. But there are only twelve
possible pairwise swaps at all (four choose two) and every one of them is
a distinct permutation, so the odd permutations are exactly those twelve
swaps. Then the permutation b must correspond to swapping two values and
leaving the others unchanged. Then all the powers of b will be equal to
either b or the identity. Neither f nor g is the identity, and b can only
be equal to one of them, so the other one isn't equal to any power of b,
and the conjecture fails.
--
Matthew Skala
[EMAIL PROTECTED] I'm recording the boycott industry!
http://www.islandnet.com/~mskala/
------------------------------
From: "Thanh Diep" <[EMAIL PROTECTED]>
Subject: Re: One-way encryption
Date: Mon, 18 Sep 2000 22:19:48 -0400
I would like to thank you all for the prompt and helpful suggestions
Regards,
Thanh Diep
Thanh Diep <[EMAIL PROTECTED]> wrote in message
news:ed8x5.11268$[EMAIL PROTECTED]...
> Hi,
>
> I am looking for an one-way encryption algorithm to encrypt passwords of
> about
> 20-character in length.
>
> I have been scanning various news group without much success. A few
> algorithms
> mentioned were: 3DES, MD5, SHA-1 and RIPE MD160, but I have no ideas where
> to
> get them or how to implement.
>
> Ideally, I would like to have an algorithm to incorporate in my system but
> will
> settle for a dll. My development platform is J++ on NT 4.0 and the
> application
> is running on the server side only. Please bear in mind that this is a
> commercial application.
>
> Thank you in advance for your help.
>
> Regards,
>
> Thanh Diep
>
> (Please send a copy of your suggestion/solutions to [EMAIL PROTECTED])
>
>
------------------------------
From: [EMAIL PROTECTED] (David A. Wagner)
Subject: Re: ExCSS Source Code
Date: 18 Sep 2000 19:47:11 -0700
Bryan Olson <[EMAIL PROTECTED]> wrote:
> The question was the purpose of CSS. It's not to control
> who can enter the player market and how they can compete.
> It's to control access to the content.
You left out a layer of indirection. The claim is that CSS
is intended to control access to the market, so that only players
which control access to content are allowed onto the market.
That's the sense in which it may be claimed to be player control.
Again, if you like, you don't have to use the words `player control'.
But the question that others have asked remains: Is the DMCA putting
fair use, First Amendment, and other rights at risk? This is way
off-topic, but cannot be settled just by calling CSS `player control'
or `content control'.
------------------------------
Date: Tue, 19 Sep 2000 01:49:30 +0100
From: David Hopwood <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: Re: A conjecture - thoughts?
=====BEGIN PGP SIGNED MESSAGE=====
Andru Luvisi wrote:
> I have the following conjecture:
>
> If f() and g() commute, that is f(g(x)) = g(f(x)) for all x, then
> f() and g() are both powers of some base function, b^y(x_0, x),
> where x_0 and x are the same the first time through, x_0 stays the
> same on every itteration, and the output is fed back into x.
x_0 doesn't add anything because it can be folded into the definition
of b. Also assume without loss of generality that the domain and
codomain of f and g are the same. So we can rewrite the conjecture as
f : S -> S
g : S -> S
if f o g = g o f, then there exist nonnegative integers y and y'
and some function b : S -> S such that f = b^y and g = b^y'.
Ian Goldberg pointed out a counterexample: f(x) = x*2 and g(x) = x*sqrt(3).
A simpler counterexample that works for the same reason is f(x) = x + 1 and
g(x) = x + c, where c is any irrational number. In that case b(x) = x + 1/y
and b(x) = x + c/y', so c = y'/y, which contradicts c being irrational.
That suggests that it might be interesting to restrict S to a finite set;
I'm not sure whether the conjecture is true or false in that case, but the
same method of producing a counterexample won't work.
- --
David Hopwood <[EMAIL PROTECTED]>
Home page & PGP public key: http://www.users.zetnet.co.uk/hopwood/
RSA 2048-bit; fingerprint 71 8E A6 23 0E D3 4C E5 0F 69 8C D4 FA 66 15 01
Nothing in this message is intended to be legally binding. If I revoke a
public key but refuse to specify why, it is because the private key has been
seized under the Regulation of Investigatory Powers Act; see www.fipr.org/rip
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------------------------------
Date: Tue, 19 Sep 2000 02:07:11 +0100
From: David Hopwood <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: Re: Q: Crypto-PC
=====BEGIN PGP SIGNED MESSAGE=====
Mok-Kong Shen wrote:
>
> A newspaper article says that there will be a crypto-
> processor for enabling secure e-commerce transactions
> done on PC and that the specification is currently
> being drafted by TCPA, Trusted Computing Platform Alliance.
> Does anyone know something about that projected processor?
There is no quick fix for PC security; at the very least the keyboard and
display need to be controlled by a secure operating system. A coprocessor
doesn't help if the input from, and output to the user is going via an
untrustworthy OS, since a Trojan that subverts the OS could simulate the
user authorising any transaction desired by the attacker, as far as can be
determined by the coprocessor.
Since writing a truly secure operating system is beyond the current state
of the art (and apart from a few interesting research projects like Eros
<www.eros-os.org>, no one is even trying to change that), I'm highly
skeptical that approaches like Crypto-PC will make any real difference.
- --
David Hopwood <[EMAIL PROTECTED]>
Home page & PGP public key: http://www.users.zetnet.co.uk/hopwood/
RSA 2048-bit; fingerprint 71 8E A6 23 0E D3 4C E5 0F 69 8C D4 FA 66 15 01
Nothing in this message is intended to be legally binding. If I revoke a
public key but refuse to specify why, it is because the private key has been
seized under the Regulation of Investigatory Powers Act; see www.fipr.org/rip
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------------------------------
From: "P.C. Teo" <[EMAIL PROTECTED]>
Subject: Re: Assistance
Date: Tue, 19 Sep 2000 11:11:38 +0800
I am from Malaysia,
I believe that LXTeo is from Singapore too.
Do you mind telling me about your project?
Teo Li Xi <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> Dear all:
>
> Does anyone here have any experience with implementing Wei Dai's
> Crypto++ library in Microsoft Visual C++ 6 environment? I need to use
> some of the algorithms in there like DES/IDEA/RSA.
>
> Regards,
> jon
>
------------------------------
From: [EMAIL PROTECTED] (Bill Unruh)
Subject: Re: ExCSS Source Code
Date: 19 Sep 2000 03:20:50 GMT
In <8q6c96$sbc$[EMAIL PROTECTED]> Bryan Olson <[EMAIL PROTECTED]> writes:
]If the book publisher included some mechanism to prevent you
]from doing so, then I agree it would be similar. He cannot
]justify "under penalty of law" unless there is such a law.
]Of course it's also similar to how movies were marketed for
]most of the time that there have been movies. In the
]theater (or on TV before the days of the VCR) we pretty much
]had to take the work as they chose to show it.
Not if you bought it. Youhad the perfect right to cut up the movie,
reedit it, insert other stuff, whatever. Of course the new work fell
under the original copyright so you could not make a copy of it, but you
could show that movie to your friends. That this was difficult and few
people did it was simply an accident of technology.
------------------------------
From: [EMAIL PROTECTED] (Bill Unruh)
Subject: Re: Software patents are evil.
Date: 19 Sep 2000 03:17:28 GMT
In <K5yx5.2195$hu1.1553@client> "Dann Corbit" <[EMAIL PROTECTED]> writes:
>An algorithm is nothing but an implementation of a mathematical concept.
>All of them. Deeper understanding of law? I doubt it, except for knowing
>the laws are absurd if (indeed) they grant ownership to math.
And manufacture is nothing but the rearrangement of matter, and matter
is not patentable either. A paper clip is but a wire which is bent. Yet
they are allpatentable. It is not the similarity between an algorithm
and a mathematical concept that makes it eligible or not for a patent,
it is the differences.
It is not the mathematical concept that is patented, it is the
implimentation in order to accomplish some specific goal that is
patentable.
The laws do NOT give ownership to math. The give "ownership" ( or rather
a monopoly) on the use of math to accomplish a certain end.
>> Patents on "processes" ("do this, do that") have been common for at
>> least a century. Patents on a computational process which ends up
>> providing some benefit for use seems a very natural extension.
>And a mathematical formulation is not ownable.
Correct.
>I realize that there is an irreconcilable difference of opinion. You
>obviously think it is just fine to own an algorithm. I think it's
>poppycock. The law says you are right and I will obey it.
He never said that. You are putting words into his mouth.
Nor does the law state that.
>No amount of wrangling will convince me that the ownership of math is OK
>under certain circumstances. I do hope that legal entanglements with this
>sort of thing do make it an entirely untractable proposition. On the other
>hand, the rest of the decay of society makes me believe that to be unlikely.
>If humans could behave in an ideal manner, the newsgroup sci.crypt would be
>completely devoid of purpose.
>--
>C-FAQ: http://www.eskimo.com/~scs/C-faq/top.html
> "The C-FAQ Book" ISBN 0-201-84519-9
>C.A.P. Newsgroup http://www.dejanews.com/~c_a_p
>C.A.P. FAQ: ftp://38.168.214.175/pub/Chess%20Analysis%20Project%20FAQ.htm
------------------------------
From: [EMAIL PROTECTED] (Mack)
Subject: Re: Algebra, or are all block ciphers in trouble?
Date: 19 Sep 2000 03:18:17 GMT
>In article <[EMAIL PROTECTED]>,
> [EMAIL PROTECTED] (John Savard) wrote:
>> Well, I've added a new page to my site:
>>
>> http://home.ecn.ab.ca/~jsavard/co041206.htm
>>
>> in which I try to generalize from the fact that, given an invertible
>> f-function, it is trivial to solve for the subkeys from known
>> ........
>> But as long as f(x) is nonlinear, it appears that one cannot go
>> further, and that Feistel-round block ciphers are safe.
>>
>
>the right address is http://home.ecn.ab.ca/~jsavard/crypto/co041206.htm
>
>it is a VERY GOOD work.
>
>but the conslusion is ony 95% correct:
>if you go writing boolean algebraic
>equation at BIT level, it can be demonstrated that
>ANY invertible f-function may be built-up by a proper
>composition of XOR and NOT function...
No any invertible LINEAR function can be build using
only XOR, the variables and if nessessary the constant 1
NONLINEAR invertible functions require the AND operator.
>(as INVERTIBLE f-function i mean ANY BOOLEAN function of N
>input bit and 1 output bit where
>by the knowledge of ANY N-1 input + the output
>it is possible to retrieve the remaining input bit).
All binary functins of N inputs and one output can
be solved for the remaining output if they are
not degenerate in the unknown input bit. Simply
try one then zero.
>Such a composition allows you to extract the unknowns
>from the "F(x,y,z)" expression:
>you may simplify your equations, because it will be made
>by XOR and NOT functions only.
>
See above ...
>...so the strongness of DES against an ALGEBRAIC attack
>resides in the EXPANSION permutation (from 32 to 48 bits)
>and the S-Box HASHING (from 48 to 32 bits),
>that constitutes a NON-Invertible f-function.
>
Yes but not for the reasons you state.
>best wishes
> Ferdinando
>
>
>Sent via Deja.com http://www.deja.com/
>Before you buy.
>
The Method of Formal Coding as this is called has
been studied since the early 80's. The requirements
of the S-box to defeat formal coding are that it have
high degree, high non-linearity and a large number
of terms as well as no high probability derivatives and
no high bit correlations.
This equates to the more common criteria of
An evenly distributed XOR and LAT.
Mack
Remove njunk123 from name to reply by e-mail
------------------------------
From: [EMAIL PROTECTED] (Mack)
Subject: Re: Hamming weight
Date: 19 Sep 2000 03:38:47 GMT
>
>On Mon, 18 Sep 2000 14:38:36 +0200, in
><8q51uh$kea$[EMAIL PROTECTED]>, in sci.crypt "kihdip"
><[EMAIL PROTECTED]> wrote:
>
>>Does anybody have an exact definition of 'Hamming weight' ??
>>(and knowledge of what 'unit' to use - do you say 0,5 ; 50% or something
>>else ??)
>
>See, for example:
>
> http://www.io.com/~ritter/GLOSSARY.HTM#HammingDistance
>
A good definition for base two. But Hamming weight is also
applicable to other bases. "The Theory of Error-Correcting Codes"
by MacWilliams and Sloane defines the Hamming Weight as
the number of non-zero entries in the numeric string and
the Hamming Distance as the number of places where they
differ or alternately the hamming weight of subtracting one string
from the other without carry.
>
>>Is a Hamming weight of 0,5 necessarily the goal for every cipher ??
>
>See, for example:
>
> http://www.io.com/~ritter/GLOSSARY.HTM#Balance
>
>---
>Terry Ritter [EMAIL PROTECTED] http://www.io.com/~ritter/
>Crypto Glossary http://www.io.com/~ritter/GLOSSARY.HTM
>
>
Mack
Remove njunk123 from name to reply by e-mail
------------------------------
From: [EMAIL PROTECTED] (Mack)
Subject: Re: CDMA tracking (was Re: GSM tracking)
Date: 19 Sep 2000 03:43:32 GMT
>In article <[EMAIL PROTECTED]>,
> Jerry Coffin <[EMAIL PROTECTED]> wrote:
>> In article <[EMAIL PROTECTED]>,
>> [EMAIL PROTECTED] says...
>>
>> [ ... ]
>>
>> > What is the exact behaviour during this periodic wakeup?
>> > Does it transmit or receive? Or does it just check a battery
>> > level and then go back to sleep?
>>
>> IIRC, it receives, but does not normally transmit. If a law
>> enforcement agency wanted to track your location using this, it would
>> be quite difficult -- it only stays on for a short period of time,
>> and they'd have only its RFI to track...
>>
>> > This has me rather curious. Is this function used to detect
>> > missed calls? What exactly is it doing?
>>
>> It's mostly just keeping its list of "nearby" base stations up to
>> date and ensuring that its clock stays in sync -- without trying to
>> go into the details, CDMA phones can't work without keeping their
>> clocks in sync with the base station. Doing this periodic update
>> while the phone is turned off allows it to turn on almost immediately
>> without having to search for nearby base stations and sync up its
>> clock.
>
>If you are concerned about your phone being
>trackable when it is off, why not just put
>it in an aluminum briefcase ?
>
Not terribly effective at attenuating signals.
It must be properly grounded. The 50 foot of ground
cable limits the effective range of the phone.
>--
>"Sarcasm: the last refuge of modest and
>chaste-souled people when the privacy of
>their soul is coarsely and intrusively invaded."
> --Dostoyevsky--
>
>
>Sent via Deja.com http://www.deja.com/
>Before you buy.
>
>
Mack
Remove njunk123 from name to reply by e-mail
------------------------------
From: "Dann Corbit" <[EMAIL PROTECTED]>
Subject: Re: Software patents are evil.
Date: Mon, 18 Sep 2000 20:54:21 -0700
"Bill Unruh" <[EMAIL PROTECTED]> wrote in message
news:8q6ls8$mnq$[EMAIL PROTECTED]...
[snip]
> >I realize that there is an irreconcilable difference of opinion. You
> >obviously think it is just fine to own an algorithm. I think it's
> >poppycock. The law says you are right and I will obey it.
>
> He never said that. You are putting words into his mouth.
> Nor does the law state that.
So if someone else implemented encryption using RC5 before the patent ran
out, there would have been no problem with that?
What exactly is owned then, if it isn't the algorithm? A hardware device
only? Can I implement the same algorithm without fear of reprisal?
--
C-FAQ: http://www.eskimo.com/~scs/C-faq/top.html
"The C-FAQ Book" ISBN 0-201-84519-9
C.A.P. Newsgroup http://www.dejanews.com/~c_a_p
C.A.P. FAQ: ftp://38.168.214.175/pub/Chess%20Analysis%20Project%20FAQ.htm
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