Who’s that p*k*m*n? It’s Encryption

Luqman M. Zagi
Aug 8, 2017 · 2 min read

I already wrote this article in my blog using Bahasa Indonesia. My friend encourage me to write “IT” related article in medium, not in w*rdpr*ss. So I thought, why not? At least i can try learn to write article in English here.


It’s took awhile to a people in Indonesia to aware that IT security’s needed by all of people, not just organization or government. Thanks to Patya and Wannacry. Those malware had a similarity, they encrypt something. Patya encrypt MBR (Master Boot Record) and Wannacry encrypt file with spesific extension (such as docx, pdf, etc). Wait, hold on who is this encrypt???

Lock and key is the simple way to represent encryption

Encrypt (verb) means convert (information or data) into a code, especially to prevent unauthorized access (oxford dict). The origin of this word is Kryptos from greek which we can translate as hidden. A primitive example of encryption is Caesar Shift Cipher. The mechanism of this encryption was where each letter is replaced by the letter after it in the alphabet is a Shift of n.

Taken from crypto Museum

I’ll make some example. This is Caesar shift cipher with n =3. If I want to write Halo, i should write Kdor. If i want to write yes, i should write bhv. And so on. To make it easier, you can see it in below.

Taken form: Maths-Resources.net Shift 3

That’s the simple sample of encryption. Now days people use arithmetics to make encryption (such as AES and RSA). Every encryption have a cycle:

Encryption cycle
  • cryptography = the art of writing or solving codes.
  • plain text = uncoded text
  • encryption = the process of converting information or data into a code, especially to prevent unauthorized access.
  • cipher text = a secret or disguised way of writing
  • decryption = make (a coded or unclear message) intelligible.

That’s all for today. Hope it’ll handy for you

Luqman M. Zagi

Written by

Berbagilah ilmu walau cuma secuil

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