Abbabbj I have a question we all know that transmitted RF from any digital source are encyrepeted we used to have old magnetic tape analog recorder so we can record analog waves (RF) my idea is to recored the transmition (of any digital device including wifi) as an analog wave on some sort of modified hard disk (to record analog)then trying to decyrept the data to know the decyreption mode can that be made?? by the way i am a Lebanese university student(biochemistry first year) so if any of my data was wrong plz correct note: i am not talking only about wifi i am talking about all rf for example the car alarm key besides i am not a telecommunicatio expert but i know that analog data forms could not be stored in any digital manner in another word if i could store allllllllllllllllll the rf i receive and then i will have time to crack the most powerful encyreption in addition to the data i have recorded {ya3ne hala2 ana sajjalet kel 2el RF signals betdall 2el data mowjoode 3ende 3atool hatta lw kenet encyrepted)
J4D this is already done digitally , no need for analog then reconvert to digital ! , research packet sniffing :) besides Wifi WEP has been cracked and WPA has a process for hacking but tough and time consuming . try the search function in the forum , we have talked about this alot (wifi cracking) :)
Abbabbj i am not talking only about wifi i am talking about all rf for example the car alarm key besides i am not a telecommunicatio expert but i know that analog data forms could not be stored in any digital manner in another word if i could store allllllllllllllllll the rf i receive and then i will have time to crack the most powerful encyreption in addition to the data i have recorded {ya3ne hala2 ana sajjalet kel 2el RF signals betdall 2el data mowjoode 3ende 3atool hatta lw kenet encyrepted)
Aj_BlaZ you need to decrypt the spectrom of that signal and then analyze it :D the hard of all of this is decrypting the spectrum of that signal imagine a signal each bandwidth have encrypted code and each code have another code you need to decrypt for example a bandwidth of 1111000010 each number have its own code you need to decrypt imagine that , thats why wifi signals can be decrypted but gsm signals can't you need a powerful pc to do all of this and oh did i mention each signal have its own spectrum yup thats right FM AM wifi gsm etc ... so its all separated what you need to do is search whats already done and try to understand it
Abbabbj thnx a lot i will do the search i have heard of millitary technology which finds the frequency of the RF i am not a electronic expert but it uses something called wide range frequency receiver chip (al defaaya magazine old issue) so we could know the the freq of each rf and thus locate it in the spectrum after that we could recored all the transmission and try to decyrept it later and since the data is stored we have more time for decyreption and thus we need less powerful processors i know that all my information may look crap for you but i was only wondering if this could be done thnx for your replies
arithma Yes indeed what you're saying there is correct. You will need a wide spectrum analyzer to catch all the existing signals. But it can't record it. Different spectrum bands require different receiver schemes due to sensor sensitivity to frequency (much like we can't hear ultra sounds that dogs can). Plus if you are trying to decipher a signal whose type you already know (wifi for example) you don't need a frequency analyzer at all since you know the bandwidth before hand (it works at certain contained spectra). Most signals whose types are standard are encrypted using publicly known algorithms but with private and public keys. Your question degrades to can we decipher signals. Jad answered it well.
nuclearcat Analog Digital Conversion is required to decode RF signal. Signal can be modulated many different ways. Sure you can just digitize some band with very high resolution and sampling rate (kind of expensive), then try to decode it later. Very possible that resolution you got will not be enough, because for example PSK decoder must rotate phase of signal then try to decode it, and QAM needs also to analyse amplitude of signal, and etc., and they use some tricks (too long to explain here), to decrease amount of job for ADC. If signal "seriously spread spectrum", probably you will need too wide band to be recorded, that also will need too much receivers (remember ADC performance is limited this days). So prefferably receiver must be built for specific kind of signal modulation. On proper analyser you can see also, what is possible type of modulation. Because you work in biochemistry - DNA decoding is much more interesting, since we dont know who, how and where encode this information.
J4D same if digital :) even better ! , you need a spectrum analyzer , it does all that... Examples there are other forms which are more powerful and computer based .
