Work Factor is defined as the amount of effort (usually measured in units of time) needed to break a cryptosystem. The Work Factor of a cryptosystem is related to its key-length and the working mechanism used (encryption and decryption algorithms). For example, if the brute force attack method is used to break the system (trying […]
One-way Hash Algorithm In cryptographic application such as digital signature, we usually operate on the message with one-way hash algorithm before we apply the sender’s private key on it. Why? It is because one-way hash algorithm can convert the message of whatever length into a fixed length code (usually of 128 or 196 bits). In […]
What can be improved so that the the susceptibility to frequency analysis attack problems of alphabetic subsitution methods like Caesar Cipher and Monalphabetic Substituion can be removed? We can use a different set of encryption mapping in the order of each alphabet encryption. Suppose we have the sentence again ATTACK STARTS ON SEVEN TONIGHT We […]
To improve Caesar Cipher Encryption, we can assign each alphabet with another one in an non-sequential manner. For example A can be mapped to D while B can be mapped to R, and so are the rest being mapped to a different alphabet. Recall that Caesar Cipher has a key space of 25, Monoalphabetic Substitution […]
One information that is truly important when conducting Cryptographic Attack, it is: the nature of the plaintext. Is it a sentence of a particular language? or is it of some software code? If we know the fundamental nature of the plaintext, then our code breaking job could be a bit easier. If it is of […]
In cryptographic study, we know the simpliest way to conceal the information is by ‘substitution’. You replace the original word/alphabet by another word/alphabetic ‘systematically’. The word ‘systemtically’ have to be in place because you need a way to decrypt the concealed message. In Latin language system, we use a alphabet to replace another one sequentially […]
The main idea of cryptography is that a group of people can use private knowledge to keep written messages secret from everyone else. The original message sent is called PLAINTEXT. The message encrypted is called the CIPHERTEXT . In both encryption and decryption process, we need a KEY to be incorporated into the process. What […]
Cryptography is the science (or Art?) of using mathematics to encrypt and decrypt data
