KEY SCHEDULE ALGORITHM ASSESSMENT OF CRYPTOGRAPHIC STRENGTH

Abstract

In recent years, the field of Information Security has grown and advanced considerably. Information Security is an area of restricting unauthorised use, access, disclosure, disruption, modification, destruction, recording or inspection to records. Information collected is processed and saved on digital computer systems and transmitted throughout networks to different computers. To guard the information in transit or at stationary, I use cryptographic algorithms. 3 kinds of cryptographic algorithms on the foundation of the keys range include: Secret Key Cryptosystem/Symmetric key Cryptosystem in which a single key is used for each encryption and decryption, Public Key Cryptosystem or Asymmetric Cryptosystem which used two keys, one for encryption (public key) and different for decryption (private key) and Hash/One-way characteristic which carried out mathematical transformation to convert a variable size enter into a constant size output and to be used as finger prints of enter data.

The protection of uneven cryptosystem lies on two parameters: the strength of algorithm and secrecy of the key. In exercise cipher algorithms are publicly acknowledged so the safety of complete cryptosystem relies upon on the concealment of the secret or essential key. The key size needs to be lengthy sufficient that there is no higher way to spoil it besides brute pressure attack. Now a days, at least 128-bit key is encouraged to be used for symmetric algorithms [1].