Introduction to columnar transposition cipher:

Welcome to this tutorial on the columnar transposition cipher, a powerful encryption technique that offers both security and versatility in safeguarding sensitive information. In this step-by-step guide, we will walk you through the process of encrypting a plaintext message using the columnar transposition cipher. This cipher involves rearranging the characters of the original message by organizing them in a grid and then reading them out column by column. The resulting ciphertext appears scrambled, making it difficult for unauthorized individuals to decipher without the proper key. Join us as we explore the workings of the columnar transposition cipher, its strengths, and its practical applications in ensuring data confidentiality.

Columnar transposition is also known as row column transpose, this simple yet effective cipher allows you to encrypt messages easily by hand. In this tutorial, we will teach you how to encrypt messages using this technique.

To get started, let's understand the basic concept. When using columnar transposition, you write your message in a column and then dismantle it to encrypt it. The length of your message determines the size of the columns. For example, if your message consists of 45 words, you would create a grid of either 9 columns by 5 rows or 5 columns by 9 rows. The left number represents the x-axis (columns) while the right number represents the y-axis (rows).

Let's start by taking the example of number 45:

For the number 45 we have 9 x 5, 5 x 9, 3 x 15, or 15 x 3.

For 9 x 5, the grid looks like this:

For 5 x 9 grid looks like this:

The 3 x 15  grid looks like this:

For 15 x 3 grid looks like this:

The 4 grids are the possible grids if 45 letters were placed into and encrypted message.

How to use a columnar transposition cipher with a rectangular array and keyword cyber to encrypt a message:

The message reads as:

“Multiple encryptions are the process of encrypting an already encrypted message one or more times, either using the same or a different algorithm."

The keyword is cyber a 5-letter word so the grid will look like this:

The encrypted message will be “leynhcfygrepeertergaaeaixMpcisrsciadrdaerehhieofnomtepseeepaentsomiiutmdrltxulrotoornlyymgoesensrftrxintipsntnacesnomtsheieghx” using the coulombs one reads it downwards starting from 1 – 5 till finished to encrypt the message.

The following message was encrypted with a columnar transposition cipher using a full rectangular array and keyword cybersecurity. Now decrypt it.

“YMIC SSRN POEG UEHU TSNP SOTC YAAU RACIL”

The table would look something similar to this:

To guess this one would need to see when words form the word SOME can be formed on the first line but the second line gets no words "YOU" can also be formed but the second line makes no sense but the word "CRYPROGRAPHY" can be formed and eventually the text comes out to "CRYPTOGRAPHY IS A MOST UNUSUAL SCIENCE".

 Thanks for reading our tutorial blog on columnar transposition. We hope you now feel confident in your understanding of this simple yet powerful cipher.