pegasus
How do i use my privite and public keyrings to encrypt email. I think that I have the file part and then use as an attatchment ok Thanks
Re: Idea: The ultimate CD/DVD auditing tool (meow)
On Wed, 9 Jul 2003, Major Variola (ret) wrote: > Yes this is for localization ---clicks are broadband, you need to > identify which freq components are used. I still think > humans can't discriminate the phase of a tone. In fact, MP3s > use this to cut bits. They can tell relative phase, but it takes a lot of training. > After the experiments, the cats > will be ok, as I assume they're sufficiently > plastic, unless you do brain staining on them. :-(Or your policy is > the > Tim McVeigh treatment. both. They spend a year training the cats, then a year or 2 collecting data, then brain stain, then vaporize. Each cat is worth about $1M when it's all done, and it's got a lot of skull missing while it's alive. But it's well protected with a lot of aluminum and epoxy :-) > Cool stuff, though my domestic feline wants to know where you live. > > PS: have you identified the "can opener sound" brain-center yet? I think you better keep it far away! And no, they don't play with higher order systems. The low level stuff is hard enough!! > Cats manage biometrics and reputation better than most human systems.. :-) Patience, persistence, truth, Dr. mike
Re: Idea: The ultimate CD/DVD auditing tool (meow)
At 11:45 AM 7/9/03 -0700, Mike Rosing wrote: >On Wed, 9 Jul 2003, Major Variola (ret) wrote: >> Actually I thought humans are insensitive to phase relations, modulo >> inter-aural timing at low frequencies for spatial location. Perhaps >> that >> is what you meant? But spatial location isn't the same as the >> frequency-fetishing >> audiophiles go for. To do that well you need casts of the outer ear >> too. > >No, if you put 2 clicks out that are 10 usec's apart on right and >left, most people can pick out which side came first. 90% of the >time anyway. Yes this is for localization ---clicks are broadband, you need to identify which freq components are used. I still think humans can't discriminate the phase of a tone. In fact, MP3s use this to cut bits. >> You doing owl-type studies on auditory localization? Audio-visual >> mapping >> and plasticity? Making the cats wear funky glasses? > >Yup. they sew coils into their eyes. For humans they use contacts :-) >PETA is definitly a problem :-) Gaak. I was thinking prism-glasses maybe bolted on that translate the vis field. Its ok for undergrads so its ok for cats. After the experiments, the cats will be ok, as I assume they're sufficiently plastic, unless you do brain staining on them. :-(Or your policy is the Tim McVeigh treatment. Cool stuff, though my domestic feline wants to know where you live. PS: have you identified the "can opener sound" brain-center yet? Cats manage biometrics and reputation better than most human systems..
Re: Idea: The ultimate CD/DVD auditing tool
On Wed, 9 Jul 2003, Major Variola (ret) wrote: > Do cats buy a lot of audiophile equiptment :8=|| Nope. That's why I have a job (for another couple of months anyway, till the grant runs out.) > Actually I thought humans are insensitive to phase relations, modulo > inter-aural timing at low frequencies for spatial location. Perhaps > that > is what you meant? But spatial location isn't the same as the > frequency-fetishing > audiophiles go for. To do that well you need casts of the outer ear > too. No, if you put 2 clicks out that are 10 usec's apart on right and left, most people can pick out which side came first. 90% of the time anyway. > You doing owl-type studies on auditory localization? Audio-visual > mapping > and plasticity? Making the cats wear funky glasses? Yup. they sew coils into their eyes. For humans they use contacts :-) PETA is definitly a problem :-) Patience, persistence, truth, Dr. mike
Re: Idea: The ultimate CD/DVD auditing tool
On 2003-07-08, Major Variola (ret) uttered to [EMAIL PROTECTED]: >I haven't, but it does ring true. You'd get 2 Khz as well as other >intermodulation products. Provided there's a nonlinearity, effective in the ultrasonic range, somewhere. Mere interference (which is what we usually refer to as "beats") doesn't give rise to intermodulation. The beat, it isn't an audible frequency per se, but double the frequency you'd need to amplitude modulate a sinusoid halfway between the original sinusoids to get an equivalent result. >You've read about the company trying to sell highly localized speakers? >They modulate two intense ultrasound beams, and the air does the >nonlinear mixing where they meet. You can do it with a single beam, too. MIT's Sonic Spotlight is one example, but there are better developed applications on the market. However, you need huge amplitudes to get the air to distort. (I've heard numbers in the 130-150dB range.) >In the audiophile, lower-intensity case, the ears' nonlinearity would do >it. I don't think it would. Before the nonlinearity gets to do its job, the sound needs to be conducted to the inner ear. But it probably won't be -- our ossicles and the tympanic membrane are too massive to operate in that frequency range. So I agree if the amplitudes are extreme, but otherwise I doubt it. -- Sampo Syreeni, aka decoy - mailto:[EMAIL PROTECTED], tel:+358-50-5756111 student/math+cs/helsinki university, http://www.iki.fi/~decoy/front openpgp: 050985C2/025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2
Re: [CI] Re: Finding collision resistant hash functions
At 02:59 AM 7/9/03 -0700, Sarad AV wrote: >hi, >> MV: >>There's nothing gained by >> increasing >> the input entropy (compressing > >I was looking for such a compression function such >that the chances of collision in the message digest >obtained by hashing these 2^80 messages is collision >free or very low probability of collision or in other >words I dont want the birthday attack to work on it. > >If i hash 2^80 messages they should be equidistibuted >in such a manner that it does not affect the security >of the algorithm. Again, unless you know something about the distribution of your input AND their interaction with your chosen hash function, you gain nothing by remapping (compression or otherwise) your input. And again, a good hash function will disperse your input randomly, regardless of its clustering. So pick a crypto-like hash function (which guarantees random dispersion) and use it. You can't do better unless you "cheat" and know your input before you pick a hash function. And picking pathological inputs (to cause collisions) will be hard. e.g., hash=0 while (input) hash = hash ^ DES( input, fixed_key ) return hash The only reason to compress would be to cut down the number of DES operations, useful only if compression is cheaper than DES.
MRAM, persistance of memory
The persistance of memory could be a problem if your melting clocks are swarmed by spooky ants. Wired has an article on magetic RAM http://wired.com/news/technology/0,1282,59559,00.html that fails to mention security implications. Obviously nonvolitile RAM presents a different security risk than RAM that forgets when powered off. Will future OSes have provisions to keep certain data out of MRAM banks, if MRAM doesn't completely displace DRAM? I doubt it. And shutting off your virtual memory swapping --useful today because of the gobs of DRAM machines have-- will no longer be useful for security. Not so obviously to the layman is how many times MRAM must be overwritten to keep the TLAs away. (Exactly analogous to scrubbing a disk.) While this is trivial to do for user-space, if the OS keeps copies of sensitive info this might require more than a huge malloc() & overwrites before shutdown.
Re: MRAM, persistance of memory
On Wed, Jul 09, 2003 at 10:23:55AM -0700, Major Variola (ret.) wrote: > Wired has an article on magetic RAM > http://wired.com/news/technology/0,1282,59559,00.html > that fails to mention security implications. Obviously > nonvolitile RAM presents a different security risk than > RAM that forgets when powered off. Will future OSes > have provisions to keep certain data out of MRAM banks, > if MRAM doesn't completely displace DRAM? > I doubt it. I doubt it as well. DRAM also has power-off memory persistence and nearly everyone in security ignores that as well. But not the spooks : "The FEI-374i-DRS is a data recovery system that captures and preserved digital data, in its original format, directly from the Dynamic Random Access Memory (DRAM) of Digital Telephone Answering Machines (DTAMs) .. The FEI-374i-DRS is an indispensable tool for forensic investigators required to evaluate residual audio and tag information retained in today's DRAM-based DTAMs." http://www.nomadics.com/374idrs.htm Eric
Grey-World
An excellent site for those interested in tunneling, covert channels, network related steganographic methods developments. http://gray-world.net/ "There is no protection or safety in anticipatory servility." Craig Spencer
Re: Idea: The ultimate CD/DVD auditing tool
At 07:15 PM 7/8/03 -0700, Mike Rosing wrote: >To produce 65kHz (for cats) my present boss prefers a 1 MHz sample rate. Do cats buy a lot of audiophile equiptment :8=|| >The human hearing system is capable of noticing phase relations at 100kHz >rates. Actually I thought humans are insensitive to phase relations, modulo inter-aural timing at low frequencies for spatial location. Perhaps that is what you meant? But spatial location isn't the same as the frequency-fetishing audiophiles go for. To do that well you need casts of the outer ear too. You doing owl-type studies on auditory localization? Audio-visual mapping and plasticity? Making the cats wear funky glasses?
Re: Genetic engineering [was: RE: DNA of relative indicts man, cuckol ding ignored]
On Mon, 7 Jul 2003, Trei, Peter wrote: > Its when we get to 'fixes' to behaviour and personality > that things start to get very hairy. I fear that those in > power will use genetic engineering as they have used > every other tool at their disposal - weapons, states, > laws, and governments - to maintain their position at > the expense of the overall welfare of the species, by > allowing improvements only to their own descendents, > while requiring changes to those out of power which > make it harder for them to change their status. > > One scenario: > > "Mr & Mrs Smith: The No Child Should Fear Act of > 2015 requires that your proposed son have the > 'bullying' gene deleted if he is to attend publicly > funded schools. This is similar to the old requirements > for vaccination - we don't want your son to endanger > other children, do we? I have long believed that the constitution of the United States (through an ammendment) should include protection against involuntary mental tampering. It should, for instance, be a constitutional right for a child not to take their Ritalin, or for an insane man not to take his meds in order to stand trial (a recent court case whose outcome I do not know). Along this line, perhaps a more general anti-tampering ammendment could include protection against the coercion that you describe above. I feel that no parent should be forced to alter their child in any way - before or after the birth. - John Kozubik - [EMAIL PROTECTED] - http://www.kozubik.com
Re: Idea: The ultimate CD/DVD auditing tool
On Wed, 9 Jul 2003, Peter Fairbrother wrote: > the nyquist/lindquist/someone-else-who-was-pissed sampling theorems are > based on the possibility of mathematically extracting frequencies from > digital information in a STEADY_STATE situation. > > That doesn't mean that a speaker will properly reproduce those frequencies. Nor does it mean the op amp driving the speakers will follow them either. High speed and power are a hard combination to build. > Consider the dynamics of energy transfer. A digital signal at > near-1/2-sampling frequency will have two datum points. The transitiion > between them will be dramatic! the possibilities of energy transfer will not > be comparable to an analogue sinusoidal waveform. > > And that's why good analogue is better then good digital. It's definitly why you need fast digital. To reproduce 20+ kHz you should use a 200kHz sample rate and have a nice filter stage before the power amp. "good digital" can do more things than good analog because the final output is good analog in both cases. The speaker driver is pure analog by definition. To produce 65kHz (for cats) my present boss prefers a 1 MHz sample rate. The guys who do bats think it's good enough for 200kHz, but my boss won't do bats - much too complex. We've got a 25 bit dac which updates at 1 MHz, but we still need a nice filter and analog output stage for 120 dB clean signals. (I'm only getting 100 dB because it costs too much to really do the best possible.) Clearly a digital system can be built that can create any wave form a speaker can follow, and it's easier to control than an analog system. The human hearing system is capable of noticing phase relations at 100kHz rates. So any sample rate faster than 200kHz is outside the range of human detection. Cats can notice phase shifts in the 200kHz range, and bats are out in the 400kHz range. Biological systems *are* impressive. But digital vs analog is a silly argument, the final stage is analog. Patience, persistence, truth, Dr. mike
Re: Idea: The ultimate CD/DVD auditing tool
I wrote: the nyquist/lindquist/someone-else-who-was-pissed sampling theorems are based on the possibility of mathematically extracting frequencies from digital information in a STEADY_STATE situation. That doesn't mean that a speaker will properly reproduce those frequencies. Consider the dynamics of energy transfer. A digital signal at near-1/2-sampling frequency will have two datum points. The transitiion between them will be dramatic! the possibilities of energy transfer will not be comparable to an analogue sinusoidal waveform. ... and i missed a bit or two. Consider the entropic uncertainty of a signal that has two-and-a-bit datums, against a sine wave. Start from zero, and go to such a waveform. Is it a constant-amplitude sine wave at frequency z? or a decaying sine at a frequency (z-at)? There's more, and it's to do with the limits of fourier and sampling theory. Say you have a wave at a frequency of z that's sampled according to nyquist theory. can you distinguish it from a wave of a frequency z - delta z? It can be done, but it takes a while, and a good few samples to do it. And a good analogue system will do it quicker. someone (hopefully not me, i haven't the time just now) can probably apply wavelet theory and get all this from steady-state theory, and tie it up in a nice package. -- Peter Fairbrother
