Fajrina Blog Spot

There are two type of crptography -> substitution and transportation. Substitution is use by use one letter to refer to another letter. This substitution divided by two type, monoalphabetic(use same letter for the whole message) and polyalphabetic(use different letter in whole message).While transportation is use by change the arragement of text and letter. This method can be divided by key and unkeyed..

example what i learn in class is:
1 2 3 4 5 6 7 8 9 10
1 T H E R E I S N O S
2 E C U R I T Y O N T
3 H I S E A R T H T H
4 E R E I S O N L Y O
5 P P O R T U N I T Y
Conclusion: for unkeyed single transportation can be develop into a matrix of 10(vertical) by 5(horizontal). This step can be try on keyed single transportation just by using matrix 10 but do not in sorting.

this is some terms that need to memorize such as :

1. Vigenere Ciphers - we must know the manual polyalphabetic cipher to perform encryption
2. Simple substitution ciphers (random) - is use for random aphabet tp improve caesar ciphers.

Other thing that i learn today is about MAC, Message Authentication Codes is key-dependent one way hash function.It accepts as input a secret key and an arbitrary-length message to be authenticated, and outputs.MAC protects both a message's data integrity as well as its authenticity.While digital signiture is use for message from particular sender and cryptography value that depends on message and sender.A digital guarantee that information has not been modified, as if it were protected by a proof seal that is broken if the content were altered.

RSA is the algorithm was publicly described in 1978 by Ron Rivest, Adi Shamir, and Leonard Adleman at MIT.The letters RSA are the initials of their surnames, listed in the same order as on the paperis an algorithm for public-key cryptography. It is the first algorithm known to be suitable for signing as well as encryption, and one of the first great advances in public key cryptography (taken from wikipedia website).