SMS-correspondence is one of the most common types of communication. In the overwhelming majority of cases, the transmitted texts do not contain confidential information, therefore they do not need any protection measures. But in the event that the transmitted text should not fall into the wrong hands, it must be encrypted.
Instructions
Step 1
Encrypting SMS messages is somewhat difficult due to the lack of a corresponding function in cell phones. There are several ways to get out of the situation, which have their pros and cons.
Step 2
Use special algorithms for encryption, the key to which only you and your interlocutor will know. For example, one of the most common and fairly reliable encryption methods is to encode a message using a book page. For example, you need to encrypt the word "text". You look for the letter "t" on the page, then you figure out which line it is on and which letter it is. If the letter is on the fifth line and is the twelfth in a row, you designate it as 5-12. The rest of the letters are encoded in the same way. Your interlocutor, having his copy of this book and knowing the desired page, will easily decipher the message.
Step 3
You can use the string permutation method for encryption. For example, you write a message into a matrix of 8 horizontal cells and 10 (or more) vertical cells. Having written a message (without spaces), you rewrite it in one line, but already consisting of vertical rows, and send it in an SMS message. Your interlocutor, who received the text, will need to re-enter it into the 8 by 10 cells matrix to read it. This method has a rather low resistance to decryption, but for simple situations it is quite applicable.
Step 4
You can significantly increase the stability of the previous method if you digitize the matrix with an arbitrary key located at the top of the table - that is, number the vertical rows. The numbering might look like this: 1-3-6-2-7-5-4-8. As in the previous method, you write vertical lines into one horizontal one, guided by the key numbers. That is, first the line under the number 1, then under the number 2, etc. To decrypt, your interlocutor must know the key.
Step 5
It is much easier to send encrypted messages using a USB modem instead of a mobile phone. In this case, convenient input from the keyboard is available to you, you can insert whole blocks of text with one click of the mouse. Encryption is carried out on a computer using special encryption programs that are easy to find on the Internet. Such programs provide very high resistance to decryption, so you can be sure of the security of your SMS correspondence.
Step 6
You can facilitate message encryption for a mobile phone by installing special software on it. You can see one of the variants of such a program here:
