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So now let's talk about this transpositions was I did not mention the definition in the terminology,

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so I now I'm going to explain this this translation.

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So I the position operational plaintext characters.

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So in substitution, so first we are substituted the Predix characters by some other characters, but

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in this we are not going to substitute a new characters, but we will change the position of those characters.

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So and it is easy to do because it's simply rearrangement of these characters.

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So let's see some examples of this.

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So which comes under translucence.

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I was the first one is called transposition cipher.

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And in this we will construct a metrics with number of columns equal to kids.

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Keyzer And so we will take a plaintext and we will take also a key Tochigi.

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So this key is a half of it consists of half of it and then write the plain text in that matrix.

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So after building the multitude number of columns said the current is four.

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Then we will create a four ColorMatrix.

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That depends on the plaintext.

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And we write in those columns laneways, the plaintext and the ciphertext from writing columns according

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to the alphabetical order of the key.

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So the key contents ABC then the first column under it is written first and the next alphabetical order

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of the column is conter, and that is the column is written next.

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So I think this will not make sense.

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I will explain with an example.

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So we we have this plaintext.

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Meet me at midnight and the keys fancy.

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So what we're going to do is we are going to create a matrix are the simple rules and columns with fancy

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Ozeki like you create a fancy at the top and the length of the keys we create the econometrics, the

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rules.

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We do not know.

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We just keep on reading in this in that matrix.

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So this is the Matrix.

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First, I have written the fancy, very fancy and I also given the order of these keys, alphabetical

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order in the fancy way we get the first and the second and they have and then end in and then rushed

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way.

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So we I have given the numbers.

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One, two, three, four.

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Now what I'm going to do in this matrix, I'm going to read the plain text.

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So the index is.

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And I'm going to meet him and after that, I cannot write further because there are only four columns

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I need to read in the next.

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Meet me at next, but not so in that I can I help write the plain text.

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And what I'm going to do is I want to write the columns elements, only the column elements.

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So the first column elements are easier to write.

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This is are considered as first.

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The alphabetical order is of use one and it comes four straight.

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That's what we do to write these columns, alphabets, p, e, etc. That is for some part of the ciphertext.

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And we need to consider the second column.

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That is this one P and Nightwatch, this one.

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And we have to write all these alphabets in the column in the laneways.

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And and if we can, the next one, it goes by three young Megson and the four EPMD and unmuted.

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And we did so.

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So in this way we have we can save Egen and the plaintext in this ciphertext using this current transportation

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so far in this case.

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We do not substitute any new value into this, we just arranged the order of this pretextual use rate,

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we hold the key and we have constructed a matrix of different.

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Of the column of the column length of this that is free and then we hold it in the prediction that matters

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and what we have done is we do not write or the.

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All right, right past the metrics, but we have created a new rose, but the column should maintain

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the length of the key, that is five columns.

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We can read any number of rows and then we will return the ciphertext as the first column and the second,

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third, fourth and fifth.

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So this is the simple column, transportation metrics.

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You can also do the retransmission metrics.

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All you have to do is you have to write the fancy as a rose and then in the current index.

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So that is the reverse of this current transmission metrics.

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So this one is the example of the transposition ciphers and the next one is relevant.

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So I'm not going to add some texture because I'm so tired in making these people is OK.

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So I'm going to explain one image.

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The plain text is this is a secret message.

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So this is some text.

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I want to send it to receiver and this is relevant encoding key.

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OK, key is the number.

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And therefore, we need to create four roles and we need to write this message as it a.

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If you control this message, the secret message you can see here is written in the first row, first

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column, and it has written down in the second row.

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And I in that address, in the photo and then we did not read, I hear.

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But we have written here like to go like this with like Montaigne's.

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Like ups and downs, ups and downs, but you're not you do not break this line, right?

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So this is how you rate this is a secret message and then it ends here.

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Now, what we're going to do is ciphertext.

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You write every element in the room, so you have to be ready yet PJI and it just as e e so that will

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be our message.

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Cipher text message.

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You can see the here and Jesus Yomi here and then ia e r e s IRS and then see us.

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So that's how you you create a site for dictionaries and so forth.

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So I will explain it again for McClarty first.

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Right.

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The plain text and then according to the key, create those many rules and what we want to lose from

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staff.

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You need to read the exact pattern.

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So like this.

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Down, up, down, up, down, up and down.

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So you need to maintain this zigzag pattern.

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You should not break this pattern.

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You should not read.

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I hear you should write according to this chain.

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And after you heard it and you need to consider the rules, the elements are the rules for and the second,

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third and fourth rule, if you combine all those rules where you get the same protection.

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So these two are the other one come these two comes under the transposition ciphers.

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And I have showed you how transposition ciphers works and they just rearrange just the plain text that

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does not introduce any new character.