MD5 – Message-Digest Algorithm

The MD5 hashing algorithm is a one-way cryptographic function that accepts a message of any length as input and returns as output a fixed-length encrypted value further used for authentication. As it is hash function so it is irreversible. MD5 hash function is severely compromised, MD5 is not collision-resistant. The weaknesses of MD5 have been exploited in the field, most infamously by the Flame malware … Continue reading MD5 – Message-Digest Algorithm

Diffie Hellman Key Exchange

In early 70’s to send a secret message, both parties (sender and receiver) have to exchange the key to encrypt and decrypt the message. Exchange secret key may lead to compromising the security, as while exchange this key if someone intercepted secret key then the interceptor can decrypt all messages. This problem is called the key exchange problem in computer science  The key exchange problem … Continue reading Diffie Hellman Key Exchange

cryptography

Cryptography – Mixture of Art and science

Being human, we always concern about our privacy. Privacy plays a significant role in our lives, right from starting on the day till the end of the day. As part of privacy, we want our data, message to be secure. A common example is when we send a text message mostly expecting that only intended recipients should receive it. So being intelligent, human started manipulating … Continue reading Cryptography – Mixture of Art and science

Deep Dive in RC4 (RC4 Source Code in C#)

RC4 (Rivest Cipher 4) was designed by Ron Rivest. It is remarkable for its speed and simplicity. It widely used in many applications and protocols. Though, there are multiple Vulnerability has been discovered in RC4.  It is a stream cipher type. It encrypt/decrypt input data one by one. In this way, the encryption or decryption can be implemented on the length of the variable. This algorithm does not … Continue reading Deep Dive in RC4 (RC4 Source Code in C#)

Symmetric encryption Cryptography

Symmetric Cryptography

This is the simplest kind of Cryptography that involves only one secret key to encrypt and decrypt information. It is also known as “Secret Key Cryptography”.   Both Sender and receiver should know the key to be able to communicate securely.   For Example: if Mahesh & Shalini wants to communicate using symmetric-key cryptography then both would have to devise key and use it for … Continue reading Symmetric Cryptography

asymmetric cryptography

Asymmetric Cryptography (Public Key Cryptography) – Part I

Asymmetric cryptography, also known as public key cryptography, it uses two distinct, yet related keys. One key, the Public Key, is used for encryption and the other, the Private Key, is for decryption. Let say Mahesh wants to send an encrypted message to Shalini, Mahesh will look for Shalini Public key and use it for encrypt the message before sending it. Then Shalini Can decrypt … Continue reading Asymmetric Cryptography (Public Key Cryptography) – Part I

types of cryptography

Basic of Cryptography (Type of Cryptography)- Part II

Cryptography categorized based on number of keys used for encryption and decryption; Below are list of cryptography catgories  Secret Key Cryptography – It is also call symmetric encryption where for both encryption and decryption uses same key. This is mainly used for confidentiality. Public Key Cryptography – It is also called asymmetric encryption; this algorithm uses two key’s one for encryption and one for decryption. … Continue reading Basic of Cryptography (Type of Cryptography)- Part II

Caeser Cipher in source code in C#

Caesar Cipher Source Code – Part I

The Caesar cipher is one of the earliest known and simplest ciphers; Created and used in 44 BC by Julius Caesar. It is a type of substitution cipher in which each letter in the plain text is ‘shifted’ with certain number of places in the alphabet. For example, if we right shift the alphabets by 3 char then we get the below text;     … Continue reading Caesar Cipher Source Code – Part I

SHA-256(Source Code in C#) – Part I

SHA-256 (Secure Hash Algorithm), is one of the cryptographic hash function, commonly used in Blockchain. It generates an almost-unique 256-bit (32-byte) signature for a text.  SHA-256 is successor hash functions to SHA-1. it is one of the strongest hash functions available and has not yet been compromised in any way.   Here is source code written in C#. I will try to give more details in next … Continue reading SHA-256(Source Code in C#) – Part I

Cryptography Hashing

What do you mean by Hashing?

Hashing is process of converting any size of data into fix size of data by performing mathematical operations. A message to be hashed is called input; the Algorithm is used to do so is called hash function; the output is called hash value.   There are many algorithm which used to generate hash value like MD5, SHA-1, SHA-256, Tiger etc.    Hash function generates a … Continue reading What do you mean by Hashing?

basic of cryptography

Basic of Cryptography – Part I

Cryptograph means secret writing, in order to make information secret we use cipher, an algorithm that converts plain text to cipher-text. Cipher has been used long before computer existance. In 44 BC Julius Caesar uses the technique now called Caeser Cipher to send message. He used to shfit the letter by 3 character.  Another great example from history, Nazis Enigma Machine used during war to translate message. … Continue reading Basic of Cryptography – Part I