A good cryptographer, however, might use the size of the words and your punctuation to help them figure out your cipher and your secret message!
For example, what English words have only one letter? Student: 'I', like 'I went to the store' and 'a' as in 'for a loaf of bread'. But 'I' would be capitalized, so 'h' in our code would have to be an 'a'! Mentor: Good! That's exactly how a cryptographer would do it as well. We don't want just anyone to figure out our cipher, so we make it harder by removing punctuation and grouping the letters in 'words' that are usually five letters long, so our message might look something like this: QHTLZ PZHZW F.
In order for someone to translate the message, they would have to use our cipher backwards. Mentor: But in order to solve the cipher they would also need to know that we used a B-shift of Student: F becomes 5, 5 minus 7 is negative 2! What happened? Mentor: You forgot to reverse the 'mod 26' calculation. Try adding it back. Student: Negative 2 plus 26 is 24, which translates to Y. Good, that makes sense.
Mentor: Shift ciphers can also work in the opposite order, where you subtract the B-shift first when you are encrypting and then add it back when you are decrypting. Let's try another kind of cipher. It is called a multiplication cipher. It is similar to the shift cipher, except that you multiply and divide instead of add and subtract. Choose an easy example word for us to use. We'll use the number 7 again, but this time we will call it 'A' so as not confuse it with the shift. The numbers are too big for our numeric alphabet, so we need to use mod 26 again.
Student: All right. Mentor: Perhaps, but now how do you decrypt it? Student: Hmmm Working backwards, W is Divide by our 'A-multiplier' is 22 over 7 which is three remainder one What do I do with that!?!
Mentor: There's the hard part! Before we divide we need to reverse the 'mod 26' operation again. As before, let's add 26 and then see if the division works. Student: Okay. That works, because 18 is our original letter 'S', but that's not really so simple anymore. Mentor: There is another method. Try this: multiply each of your numerical alphabet code numbers by fifteen and then mod Student: W is 22, times 15 is , mod 26 is 18, which is 'S' E is 4, times 15 is 60, mod 26 is 8, which is 'I' G is 6, times 15 is 90, mod 26 is 12, which is 'M' B is 1, times 15 is 15, mod 26 is 15, which is 'P' Z is 25, times 15 is , mod 26 is 11, which is 'L' C is 2, times 15 is 30, mod 26 is 4, which is 'E'.
Mentor: Modular arithmetic is not quite the same as regular arithmetic. In modular arithmetic a multiplier will only have an inverse if the multiplier for example 7 , and the modular base in our case, 26 have no common factors greater than one!
The modular inverse - we will call it A' A-prime - will be a whole number that also has no common factors with the modular base. Student: Is there a way to figure out what the modular inverse of a number is? Start by making a list of multiples of 26, and then add one to each of them.
Mentor: That should be enough. Now we know that all of those numbers, mod 26 is equal to 1. Are any of those numbers evenly divisible by seven? Student: Yes, divided by 7 is Mentor: What if we wanted to use the multiplier 9 instead? Does 9 have an inverse? Student: Hmmm. Mentor: In mod 26, yes. If we used a different modulus, different numbers would have different inverses, and some would not have any inverses at all.
Student: Like when they share a common factor with 26, right? Why is that? Mentor: Let's see why by using the number 6, which shares the factor 2 with Does this pattern continue? Mentor: Yes. Restart your PSP and turn it back on.
It will come up with another error which is OK as well. Restart it again and you will have PSP firmware version 1.
You can grab the MPH downgrader and 2. I've noticed that it won't run all decrypted. BIN to on and use copy load For now, only PES5 works this way, it seems there's still another problem to get the other games to work, but am still working on it BIN' turned ON and enjoy! Now, look at the top listings again and select "Tools" Check the box labeled "Enable Stream Processing" Last edited by a moderator: Jan 11, RavenLife , Jan 13, RavenLife , Jan 14, Jalathole : I read in the previous thread that you have new iso games in your website, like The Sims2 and Kingkong.
Firstly, i think pspearth is down coz i only get an access denied message everytime i try to go to your website. Second, can the umdemulator V0. I also read that the v0. It doesn't bother me much but it would be better if i don't see it anymore, LOL Thanks a lot. Just a few people who knows what to do. In many tutorials we have been told to press the "??? Look at the pic. In my fastloader, it shows eg.
ISO , when i select on it, there is no respone. Btw, thanx for the guide, it's very useful.. But i still have question, hope u could help me.. Based on your guide, it looks like we can upgrade to 2.
OR that guide only used for 1. Thanx before.. Here is the story. A bunch of people said that they have v1. Then they trick their psp v. And it works. Does anyone in here have any common about this? I still dont beleive this.
TheReturn , Jan 29,
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