Cryptography and Symmetric Cipher Model
In everywhere transmitting data in a secure manner is very important. It involves many things, one of the many thing is encrypting the data to avoid to knowing from the unknown persons. We can achieve this with the Cryptography.
Cryptography: There are some important terms in Cryptography, those are plaintext, ciphertext, encryption, and decryption. Plaintext is nothing but original text, ciphertext is the text after encrypting the plaintext, encryption is the process of converting the plaintext to ciphertext, and decryption is the process of converting the ciphertext to plaintext at receiver. Cryptography is nothing but study of encrypting the data and it is called as Cryptographic system. Decrypting the data without knowledge of encryption is called Cryptanalysis. Combining Cryptography and Cryptanalysis is called Cryptology.
Symmetric Cipher Model:
Basically Symmetric Cipher model contains five ingredients. Those are Plain Text, Encryption Algorithm, Secret Key, Cipher Text, and Decryption Algorithm.
The Symmetric Cipher model works as shown below.
Plain Text: As shown above Plain Text is nothing but original message need to pass.
Encryption Algorithm: This encrypts the Plaintext based on various calculation written in algorithm and Secret key.
Secret Key: Secret Key is the input to Encryption algorithm and it is independent of Encryption algorithm and the plain text. Depends on Secret Key, Encryption algorithm will produce the different output for plain text.
Cipher Text: Cipher text is nothing but encrypted format of Plain Text which is the output for Encryption Algorithm.
Decryption Algorithm: It decrypts the Cipher Text into Plain text based on Decryption Algorithm and Secret Key. That means Decryption Algorithm takes Cipher Text, Secret Key as inputs and produces the Plain Text back based on calculations in Decryption Algorithm.
In Symmetric Cipher model we must have strong Encryption algorithm. Even if someone knows the Encryption algorithm and Cipher Text, they should not able to decrypt the cipher text without Secret Key. In this model we have to maintain the Secret Key should be stored in very strong secure place, only Sender & Receiver should know about that.
In my next article I will explain implementation of Symmetric Cipher Model in C#.
