# Security Testing Cryptography

## What is Cryptography?

The process of encrypting and decrypting the data is called Cryptography. It facilitates the users to store vulnerable data or transmit it through insecure networks so that it is able to read only by the expected recipient.

Data that can be read and understood without any particular measures is known as plain text where as the method of distinguishing plain text for the sake of hiding its stuff is known as encryption.

Encrypted plain text is called as cipher text and the process of returning back the encrypted data to plain text is called as decryption.

• The study of examining and deciphering secure communication is called as cryptanalysis. The people who perform the same are known as attackers.
• Cryptography may be either strong or weak and its strength is calculated by the time and resources it would need to reclaim the original plain text.
• So appropriate decoding tool is necessary for breaking the strong encrypted messages.
• There are some cryptographic methods available with which even a billion computers performing a billion checks a second, it is not feasible to decipher the text.
• As the power of computing growing day by day, everyone shpuld make their encryption algorithm very tough for safeguarding it from the attackers.

## How Encryption Works?

A cryptographic algorithm functions in association with a key(can be a number, phrase or word) to encrypt the plaintext and the same plaintext encrypts to various ciphertext with various keys.

Hence, this encrypted data is entirely reliant couple of parameters i.e- the strength of the cryptographic algorithm and the confidentiality of the key.

## What are the Cryptography Techniques?

Symmetric Encryption -conventional cryptography, also called as Conventional encryption. Here, a single key is employed both for encrypting and decrypting.

Below are some examples: DES, MARS by IBM, Triple DES algorithms, RC2,RC4, RC5,RC6.

Asymmetric Encryption - Asymmetric Encryption is Public key cryptography that employes a pair of keys for encrypting the data: a public key, that encrypts the data, and a private key employed for decrypting the data. Public key is displayed to the people when keeping the private key secret. Eg: Digital Signature Algorithm (DSA), RSA, Elgamal

Hashing - Hashing is ONE way encryption, which the scrambled result that cannot be inverted or at least cannot be inverted simply that is used to validate the nobelity of data.

Below are some examples: MD5 algorithm. It is employed to create, Storage of passwords , Digital signatures, Digital Certificates ,Verification of communications.