21-05-2010, 08:51 PM
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Chapter 1
INTRODUCTION
Secrecy is certainly important to the security or integrity of information transmission. Indeed, the need for secure communication is more profound than ever, recognizing the fact that conduct of much of our commerce, business and personal matters is ever being carried out today through the medium of computers, which has replaced the traditional medium computers.
Recently, the number of individuals and organizations using wide computer networks for personal and professional activities has increased a lot. Among them, there are several applications highly sensitive to data security such as commercial exchange on the Internet and smart cards. A cryptographic algorithm is an essential part in network security. A well-known cryptographic algorithm is the Data Encryption Standard (DES) and which is widely adopted in security products. However, serious considerations arise from long-term security because of the relatively short key word length of only 56 bits and recently from the highly successful cryptanalysis attack.
Another cryptographic algorithm is International Data Encryption Algorithm (IDEA) and, which is considered one of the most important post-DES cryptographic algorithms due to its high immunity to attacks. The IDEA algorithm overcomes the problems of DES algorithm. IDEA is highly secure. As key lengths increase, the number of combinations that must be tried for a brute force attack increase exponentially. For example a 128-bit key would have 2^128 (3.402823669209e+38) total possible combinations. For example, to theoretically crack the 128-bit IDEA key using brute force one would have to:
Chapter 1
INTRODUCTION
Secrecy is certainly important to the security or integrity of information transmission. Indeed, the need for secure communication is more profound than ever, recognizing the fact that conduct of much of our commerce, business and personal matters is ever being carried out today through the medium of computers, which has replaced the traditional medium computers.
Recently, the number of individuals and organizations using wide computer networks for personal and professional activities has increased a lot. Among them, there are several applications highly sensitive to data security such as commercial exchange on the Internet and smart cards. A cryptographic algorithm is an essential part in network security. A well-known cryptographic algorithm is the Data Encryption Standard (DES) and which is widely adopted in security products. However, serious considerations arise from long-term security because of the relatively short key word length of only 56 bits and recently from the highly successful cryptanalysis attack.
Another cryptographic algorithm is International Data Encryption Algorithm (IDEA) and, which is considered one of the most important post-DES cryptographic algorithms due to its high immunity to attacks. The IDEA algorithm overcomes the problems of DES algorithm. IDEA is highly secure. As key lengths increase, the number of combinations that must be tried for a brute force attack increase exponentially. For example a 128-bit key would have 2^128 (3.402823669209e+38) total possible combinations. For example, to theoretically crack the 128-bit IDEA key using brute force one would have to: