CryptographyISBN-10: 8793379102, ISBN-13: 978-8793379107 Introduction[Back] The Internet we have created is often untrustworthy and full of risks. This is partly due to the lack of security build into the services and protocols that we use. In the 21st Century, for example, we often still cannot tell if the email we have received is actually from the person who says it is from, and that no-one has read our email on the way. In fact, we can’t even tell if the email has been tampered with. The next generation of the Internet and its services must be built in a trustworthy way, and it is cryptography which provides the core techniques for us to keep things secret, to identify things, and to validate trustworthiness. Unfortunately, there is no one technique which will provide all of these things, and we often have to intertwine methods together in other to create trustworthy systems [Amazon] ChaptersThe following defines the chapters in the book:
AddendumOn Page 83, the text should read: Now, we can use key entropy which will determine the equivalent key size for the limited range of key. Key Entropy\(=log_2(Phrases)=\frac{log_{10}(Phrases)}{log_{10}(2)}\) For our 8 character passwords, we can determine the equivalent key size of: Key Entropy\(=log_2(26^8)=\frac{log_{10}(26^8)}{log_{10}(2)}=37.6\) bits Thus if we are using a 128-bit encryption key, we are not using an equivalent of 50 bits, which considerably reduces the strength of the encryption process. And the table is: |