Book Image

TLS Cryptography In-Depth

By : Dr. Paul Duplys, Dr. Roland Schmitz
Book Image

TLS Cryptography In-Depth

By: Dr. Paul Duplys, Dr. Roland Schmitz

Overview of this book

TLS is the most widely used cryptographic protocol today, enabling e-commerce, online banking, and secure online communication. Written by Dr. Paul Duplys, Security, Privacy & Safety Research Lead at Bosch, and Dr. Roland Schmitz, Internet Security Professor at Stuttgart Media University, this book will help you gain a deep understanding of how and why TLS works, how past attacks on TLS were possible, and how vulnerabilities that enabled them were addressed in the latest TLS version 1.3. By exploring the inner workings of TLS, you’ll be able to configure it and use it more securely. Starting with the basic concepts, you’ll be led step by step through the world of modern cryptography, guided by the TLS protocol. As you advance, you’ll be learning about the necessary mathematical concepts from scratch. Topics such as public-key cryptography based on elliptic curves will be explained with a view on real-world applications in TLS. With easy-to-understand concepts, you’ll find out how secret keys are generated and exchanged in TLS, and how they are used to creating a secure channel between a client and a server. By the end of this book, you’ll have the knowledge to configure TLS servers securely. Moreover, you’ll have gained a deep knowledge of the cryptographic primitives that make up TLS.
Table of Contents (30 chapters)
1
Part I Getting Started
8
Part II Shaking Hands
16
Part III Off the Record
22
Part IV Bleeding Hearts and Biting Poodles
27
Bibliography
28
Index

4.3 Information-theoretical security (perfect secrecy)

The historical roots of encryption are in military and diplomatic communications. The first encryption schemes were perhaps invented by the ancient Greeks and Romans. These encryption schemes have survived until today in the form of examples for easily breakable ciphers and can be found in virtually any textbook on cryptography.

Another famous historical example is provided by the Enigma encryption machine, which was used by the Axis powers in World War II. Due to its large key space, this sophisticated rotor-based machine was deemed unbreakable by its inventors. However, building on the work of Polish mathematicians and using (for the time) massive computing power, the Allies were able to prove them wrong [171]. Judging from these historical examples, one might get the impression that all encryption schemes can be broken. However, it is possible to devise provably secure encryption schemes.

An encryption scheme that is provably...