Security is a very broad subject that encompasses many aspects. The kind of security every internet user is looking forward to is the network security feature. The most important aspect of network security is cryptography. The word cryptography in Greek means “secret writing”. It refers to the science and art of transforming messages to make them secure and immune to attacks. The science that’s deals with cryptography is really complex as a cryptographic expert must have a decent knowledge of subjects like mathematics, electronics and last but not the least he or she must have a programming background.
Let us first understand the mechanism behind cryptography. What happens in normal life is that, one sends a confidential message to the receiver, which may be hacked in between the path by a professional cryptanalyst. The reasons for hacking can vary from situation to situation. Now this is a serious aspect with the security of a person using internet. The only way to transfer confidential information through internet is by changing its form. This is what cryptography means.
The original message before being transformed is known as plaintext. This is the message which you want to send to the receiver. After the message is transformed, it is known as cipher text. An encryption algorithm transform the plaintext to cipher text decryption algorithm transforms the cipher text back to plaintext. The sender uses an encryption algorithm, and the receiver uses a decryption algorithm.
Some of the most important ciphering techniques used are:
· Symmetric key cryptography: in this kind of cryptographic technique the sender changes every alphabet with another alphabet using a key. Like A is replaced by D if the key used is 3. The receiver in advance knows the key and he can easily use the key in opposite way to convert the cipher text to the original text. But these techniques are not as secure as other methods because the cryptanalyst can easily decode the cipher text.
· DES (data encryption standard): this is one of the best cryptographic techniques used by the senders. It uses a 64 bit key to convert the plaintext to cipher text. The process contains 19 rounds of transpositions and substitutions making it really hard core for the cryptanalyst to even come closer to decode the text.
With increasing knowledge about the cryptography among the cryptanalyst, we require even more stringent algorithms to save our text from being misused.
by Camila 1 year ago
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