benbenrf
Member
I'm not sure why the encrption thread was closed .... perhaps the Mod saw it slipping into a war of words - in that case a good thing - but if no one has an objection, I'll briefly compare the 2 (i.e. scrambling versus encryption) - so its clear.
KS4VT's comments were bang on the mark - so-called "scrambling" and "encryption" are 2 very very different things.
There are several scrambling methodologies, one of the most common is indeed the so-called "Inversion" type. It is easily demodulated back into legible audio (and video for that matter) - if you know what you are doing $20 spent at Radio Shack will be sufficient to purchase the circuit components required to re-invert such a signal - at either the RF or IF stage, and it is even more easily done if you digitise the analouge IF, and then write a small software program to deal with the so-called Inversion.
Encryption
Encryption is a completly different thing - it's an apple and orange comparison - and here to there are many methodologies, adopted for encryption, many of which revolve around logs' based on prime numbers.
Remember the days when chips/hardware was capable of running math logs that ran to 56 bits?
Then came 128 bits, then came 256bits - and now some of the commericial cyphers are starting to come out on 512bits!
The options on a 512 bit prime number? - something equivilant to all the grains of sand on all the beaches of the world - and your pc, running in parrellel with every other pc for a 100mile radius around you, starting today on an attempt to find the correct prime number for any given 256bit or 512bit encryption key, will still be running through the options in a 100years time at a rate of something like 1000 caluclations a second!
Don't hold me to the exact figure guys, but the above is a fairly realistic representation of the size of the "problem" and gives an idea of whats involved. If anything, my representation above is probably a conservative reprsentation of the figures involved!
There are NO commerical receivers availible which come ANYWHERE near close to been able to resolve 128bit encryption logs, let alone 256bit logs, and as for 512 bit .... well, just don;t even think of going down that road - and neither are their any mil spec receivers capable of standalone de-cryption at this level.
The "power" to resolve such encryption (as opposed to de-scrambling) lies not in receiver rf/if technology, but in computer processing power attached to the computer (usulay through the IF outputs, which is digitised as a first step to then be processed through attached hardware and software programs)
If you have the key (the prime number), you can process the digitised IF through any top grade SDR (e.g. Spectrum Signal Processing make SDR's and hardware/software for the various services for just such tasking), but without the key ............. thats why organisations like GCHQ (UK) and NSA (USA) exsist - and get the enourmous budgets they do.
De-cryption (?) guys, it is simply lights years beyond the scope of any commercial/COTS receiver found on the open market today - and when/if anyone does come across one - let me know, I'll put you touch with a man who'll give you a blank check. That is how avalible such intellectual knowledge is!
KS4VT's comments were bang on the mark - so-called "scrambling" and "encryption" are 2 very very different things.
There are several scrambling methodologies, one of the most common is indeed the so-called "Inversion" type. It is easily demodulated back into legible audio (and video for that matter) - if you know what you are doing $20 spent at Radio Shack will be sufficient to purchase the circuit components required to re-invert such a signal - at either the RF or IF stage, and it is even more easily done if you digitise the analouge IF, and then write a small software program to deal with the so-called Inversion.
Encryption
Encryption is a completly different thing - it's an apple and orange comparison - and here to there are many methodologies, adopted for encryption, many of which revolve around logs' based on prime numbers.
Remember the days when chips/hardware was capable of running math logs that ran to 56 bits?
Then came 128 bits, then came 256bits - and now some of the commericial cyphers are starting to come out on 512bits!
The options on a 512 bit prime number? - something equivilant to all the grains of sand on all the beaches of the world - and your pc, running in parrellel with every other pc for a 100mile radius around you, starting today on an attempt to find the correct prime number for any given 256bit or 512bit encryption key, will still be running through the options in a 100years time at a rate of something like 1000 caluclations a second!
Don't hold me to the exact figure guys, but the above is a fairly realistic representation of the size of the "problem" and gives an idea of whats involved. If anything, my representation above is probably a conservative reprsentation of the figures involved!
There are NO commerical receivers availible which come ANYWHERE near close to been able to resolve 128bit encryption logs, let alone 256bit logs, and as for 512 bit .... well, just don;t even think of going down that road - and neither are their any mil spec receivers capable of standalone de-cryption at this level.
The "power" to resolve such encryption (as opposed to de-scrambling) lies not in receiver rf/if technology, but in computer processing power attached to the computer (usulay through the IF outputs, which is digitised as a first step to then be processed through attached hardware and software programs)
If you have the key (the prime number), you can process the digitised IF through any top grade SDR (e.g. Spectrum Signal Processing make SDR's and hardware/software for the various services for just such tasking), but without the key ............. thats why organisations like GCHQ (UK) and NSA (USA) exsist - and get the enourmous budgets they do.
De-cryption (?) guys, it is simply lights years beyond the scope of any commercial/COTS receiver found on the open market today - and when/if anyone does come across one - let me know, I'll put you touch with a man who'll give you a blank check. That is how avalible such intellectual knowledge is!
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No debate/flame here, just making a funny.
