Cryptography

Short Description
Cryptography is where security engineering meets mathematics. … promote computer security research while suppressing cryptography). It reminds me of …

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Content
Security Engineering: A Guide to Building Dependable Distributed Systems
73
CHAPTER
5
Cryptography
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5.1 Introduction
Cryptography is where security engineering meets mathematics. It provides us with the
tools that underlie most modern security protocols. It is probably the key enabling
technology for protecting distributed systems, yet it is surprisingly hard to do right. As
we’ve already seen in Chapter 2, “Protocols,” cryptography has often been used to
protect the wrong things, or used to protect them in the wrong way. We’ll see plenty
more examples when we start looking in detail at real applications.
Unfortunately, the computer security and cryptology communities have drifted apart
over the last 20 years. Security people don’t always understand the available crypto
tools, and crypto people don’t always understand the real-world problems. There are a
number of reasons for this, such as different professional backgrounds (computer science
versus mathematics) and different research funding (governments have tried to
promote computer security research while suppressing cryptography). It reminds me of
a story told by a medical friend. While she was…