Customer Reviews

Understanding Cryptography: A Textbook for Students and Practitioners

5 star:		(12)
4 star:		(0)
3 star:		(0)
2 star:		(1)
1 star:		(0)

 

 

I came across this book on accident. I was googling around for articles by Preneel and found this book, in which he wrote the foreword. Frankly, I hope this book eventually replaces most, if not all of the mainstream texts on cryptography. My only complaint about this book is that I no longer feel like one of the rare geniuses that thoroughly and completely understands cryptography. Thanks to this book, any dummy off the street can understand cryptography nearly as well as I do and they do not need a computer science or math degree. No prerequisite knowledge is required, other than the ability to read but there is plenty of math if you want to study it. (Warning: I might be exaggerating a little. I really enjoy math and might be taking my math skills for granted. Just so I am clear, this is a Math textbook, which means the encryption algorithms are formally defined using math notation. However, the author's explanation of the math & algorithms is the most clear and easy to understand I have ever seen; which to me means, you do not need a strong background in mathematics to understand this material.)

The following categories are scored 1-10. 1 being the lowest, through 10, the highest...

- Readability (i.e. authors style of writing, is he to the point, write clear, how does he approach the topic, does he motivate, etc...)
Score: 10
I personally do not care for analogies in cryptography books. If the author knows what he is talking about and can explain it, there is absolutely no need for stupid analogies. Another thing that drives me crazy is authors that "challenge you to think" too much. They can never get to the point and come right out and tell you something. Half the time, I can't figure out if they actually either do not know what they are talking about, or they simply do not know how to explain something and hide it behind a series of challenging questions...which they themselves cannot answer(as if to be objective or something). Frankly, I am a professional with over 10 years of experience. I do not buy books so that authors can beat around the bush with their knowledge; which, by the way, I find condescending, because they are supposed to be the experts. When I pay money for a technical book, I do it with the expectation that the author is knowledgeable, qualified to write about the topic, and will not waste my time playing mind games with me. That is what is so surprising about this book; it clearly says "textbook" on the cover, which made me hesitate, thinking... maybe this is too elementary, or like many college textbooks, challenges you to think too much. However, contrary to my concerns, this book is to the point and carefully explains details that other authors seem to miss. In addition, it is very practical coverage and still challenging enough to be motivational, in other words, you do not have to drink twelve cups of coffee just to get through it. To summarize this section, at this stage in my career, I really appreciate authors that can "thoroughly explain things in the fewest possible words, while still being crystal clear!" (Apparently, this is something I myself cannot do, as evidence above, but that is why I do not write books)

- Organization
Score: 10
I have many cryptography books that talk about critical aspects of the encryption processes in isolation without tying them together; this book is very well organized in that respect.

- Real world Application (i.e. is this how it works in the real world or is this just theory that never gets used in practice)
Score: 9
This is another category that makes this book stand out because the coverage is very practical.

- Thoroughness (i.e. how rigorous is the book, is it a comprehensive review of technologies)
Score: 7
Great Introduction to many areas!

- Application & Implementation on Computer (i.e. code, algorithms, data-types, programming language tips/tricks...etc)
Score: 5
Most books attempt to provide code but the code is based on static input and is poorly written, leaving you to wonder, why on earth they even bothered to try. Actually coding algorithms is not the focus of this book... I don't think it contains one line of code, but you can encrypt and decrypt, end-2-end on paper, if you want to, after reading it. As I mentioned earlier, this is a math book, so the algorithms are presented in mathematical notation.

............
Edit: I have to add a disclaimer to this review. I originally read this book when I was knee deep in research and loved this book so much because the author tied together some concepts in such a concise explanation. This book is definitely a five star book but now that my initial excitement has worn off I think that some of my claims above may have been overinflated. I would recommend that the reader is comfortable with at least advanced algebra and discrete math. Sorry, I think I drank too much coffee before writing this review. Bottom line, this is not a detailed comprehensive book on cryptography, this is a short, concise, math based explanation about selected topics. The point that I was trying to make is not that this is a thorough book, but this is a high quality explanation of selected topics.

It is a summer tradition for me to pick a technical topic, find a textbook that represents the subject from an introductory point of view, and self-study as much of it as I can. This summer, I picked cryptography. After searching all over the place for a decent introductory book on the subject, I stumbled upon this one. Even though it only had 2 reviews at the time, I could tell that it was exactly what I was looking for. After reading the first 6 chapters of this book, all I can say is this: WOW!

Cryptography lies at the intersection of mathematics, computer science, and electrical engineering. This book borrows ideas from all 3 fields in order to describe the core ideas of cryptography in a surprisingly elegant way. The tone of the book is formal enough so that the book isn't disorganized or overly verbose, but not too formal that it makes the readings a chore.

As stated above, the content of the book is highly organized. The first 5 chapters deal with symmetric algorithms, and the next 5 or so deal with asymmetric algorithms. The last few chapters deal with hash functions and message authentication algorithms. In between highly-technical sections, you will find informal topics that are concerned with general security topics, history, or similar subjects. These sections are a wonderful break from the technical ones, and make this highly technical book read somewhat like a novel.

The figures in this book are wonderful, and really help the reader understand the encryption algorithms more fully. For example, the DES algorithm is somewhat convoluted, but the figures in the chapter make it very simple to see exactly what is happening at each stage of the process. Every permutation, bit slicing operation, and XOR operation is clearly evident from the flow diagrams. These diagrams, the mathematical descriptions of the encryption schemes, and the interesting discussions that follow make learning cryptography very simple!

After reading chapters 3, 4, and 5, I decided to make my own DES implementation in Python. Even though the book gives a wonderful description of the inner-workings of the DES algorithm, it doesn't provide many plaintext-key-ciphertext examples that can be used to test out my own implementation. I had to search Google for quite some time and use many different references to make sure that my implementation worked correctly. Thus, one of my only complaints about this book is that it doesn't go into quite enough technical details at some parts. I felt the same way when trying to implement the 3DES algorithm with modes other than ECB. The book doesn't seem to provide an answer as to how to combine 3DES with OFB or CBC, and I haven't quite found an answer on Google yet. However, this isn't meant to be a handbook of cryptography. It is meant to provide an understandable introduction to cryptography which will make the reader be able to keep up with more advanced books. This book does that perfectly.

It doesn't matter too much, but I'll include this anyway: I found a tiny error in chapter 2, and I told the authors about it. They very VERY friendly, and were very appreciative. It doesn't really change the quality of the book, but its nice to know that the authors really care about the quality of their work.

If I had one more complaint, it would be that this book is so interesting that it keeps me up until 3 AM every night! I miss sleeping!

I used the book "Understanding Cryptography" as text book for a basic course in cryptography. It is execellent structured, compact and clearly written and reaches the goal to be "Understandable". It offers a basic course, but it opens many possibilities to deepen the content and to explain the mathematical background. It fills a gap of well known cryptographic bestsellers, which are too detailled for a basic course. It is suitable also for engineers and students, who want to learn actual cryptography by self study. It contains the cryptographic mechanisms and algorithms, which are (or should be) used today (2010), for example presenting Elliptic Curve Cryptography not as an exotic cryptography, but as state of the art. Thanks to the authors, also for the well designed exercises.

This book targets the educational market and does a wonderful job. It introduces the basic concepts used in cryptography without going into too much detail. As such, it allows the reader to still see the wood for the trees (which is not equally true for other books on cryptography). Subjects like AES and ECC are explained exactly at the right level of abtraction. The book can be used by computer scientists, applied mathematicians, and electrical engineers. It can be used as a textbook in class or for self-study.

If you've heard people mention things like ECC, HMACs, discrete logarithms and wanted to what they were talking about; or if you wanted to understand who RSA and AES really work along with many other things, then this is the book for you.

I had been hunting for something more current than the 1996 Applied Cryptography: Protocols, Algorithms, and Source Code in C, Second Edition when I came across Understanding Cryptography. I could tell from the available samples and the table of contents, that it should meet my needs. It has not only met my needs, but has exceeded them in every respect.

This book was absolutely perfect for me, so it would be of some use for you to know my background.
I've long had an interest in cryptography but never any training. When I read Martin Gardener's famous 1977 article on RSA I thought it was the coolest thing ever, but I didn't fully grasp it and didn't pursue it at the time. In college I studied some math, but my degree is in linguistics, not in math or computing. I have read popularizations of cryptography, and had tried to make it though Applied Cryptography when it first came out in 1996, but I can't say that I really understood how the algorithms and the more intricate protocols worked. So that is roughly my background.

One of the great things about Understanding Cryptography is that it taught me exactly the math that I needed. You need to be comfortable learning new math. (I also found that I had to brush up on basic linear algebra on my own to understand one component of the deals of AES).

Working though this book on my own through self study took time. It is extremely well presented (with the possible exception of the final chapter, which could do with another round of copy-editing). The subject matter is not simple, so if you really wish to understand them you need to go through things very slowly, stopping frequently to check understanding, but everything you need is in the book without it being overly long. The excellent organization and presentation of the material means that I was able to get far, far more out of this book than anything else I have read on the topic.

The problem sets at the end of each chapter progress from easy to more challenging. I still need to go back and take on some of the more challenging ones I skipped the first time through. Often I was too eager to get to the new chapter than to work through the problems. As a consequence I missed some of the extended material that was presented through those problems sets.

Personally, my second favorite chapter is the chapter on AES which really steps through how it works and why each component does what it does. My favorite is the chapter on ECC. I had known wat ECC was used for, but before reading this, I had no idea of what it really was. Now I find it "the coolest thing ever". (OK, I may over use that phrase.) The authors' presentation of it is just right. They lead you though the process so that you can share in the delight of how ECC works.

Although I have worked though this as complete self-study, I would have preferred to do this as part of a class or at least some study group. Sometimes because I could have more quickly gotten through things that I held me up a few times, but mostly because I would have liked to share the experience. My wife and daughter are not entirely happy with the fact that I've been trying to teach them bits of what I've been learning over the month.

There are still bits that I don't fully understand. Some are questions not addressed in the book, but the further readings and bibliography are excellent. So I have the resources to investigate those. There are also bits that I don't fully understand because I haven't gone back and worked through the relevant exercises in the problem sets.

What I would like to see in a second addition:

(1) A bibliography for each chapter as well as the comprehensive one at the end
(2) A reworking of the final chapter, which appears rushed and not as well presented as everything else
(3) More on hash functions reflecting what is being learned now as part of the SHA3 process.

I am sure that this makes an outstanding textbook for a college course in the matter, but I want to add that it is so clearly presented, organized with introductions to the necessary math that it works for self-study as well.

This is the most accessible introductory cryptography text available. The math needed to understand the cryptographic topics is introduced as needed and explained clearly so that unfamiliar readers won't have any undue trouble understanding the material. The authors offer proofs and examples to clarify concepts as needed. I would recommend this as a first cryptography book for any reader not already well versed in number theory and abstract algebra.

The biggest problem with Crypto is availability of good books, and literature that beginners can understand. I have looked at at least half-dozen books on Crypto till now, but all of them lacked in some way or the other - too much math, lot of assumptions, not self-contained, and so on. This made it very difficult for a beginner to continue through the book, somewhere you got lost, and then dropped the book. I am sure all have picked up at least one Crypto book, and then left it halfway through, since it became "too difficult to follow".

Once in a while, a book comes along, that changes the game completely. This is it. It makes very difficult and arcane topic available to the beginner, and then helps build on it slowly and steadily. Don't make a mistake - this book is not a mere introduction, or superficial, but deals with important Crypto topics in sufficient detail. It is helpful for the student, as well as software professionals. The material is presented in a very logical manner, and appropriate math is introduced wherever necessary. This makes the "context switches" very few, and helps maintain a high level of interest throughout the book. The thickness of the book is also maintained reasonable, so you have even more motivation to continue to the end (thickness of the book o< 1 / (motivation to complete)).

I thoroughly enjoyed this book, and have learned quiet a few ideas along - ideas that I always though I knew. Highly recommended, five star book.

I downloaded the free Kindle sample and found it had many mathematical statements that were not quite correct. The statements confused me on multiple occasions until I figured out they were typos (by comparing with the Look Inside preview on Amazon). The typos are probably caused by someone OCR-ing the textbook to create the Kindle version, and they didn't put any effort in verifying the result. I'm getting the printed book instead.

It's too bad the publisher is allowed to sell a Kindle version that is full of typos.

First of all, this book is very well structured. That means one can read it as an absolute beginner in cryptography and find parts of the book which will make the subject of cryptography clear and interesting. Authors found a way to give just insight in often complicated cryptographic algorithms without involving rigorous mathematical concepts. On the other hand, this book is interesting even for professionals, especially practitioners who will find many timely, relevant things inside (cryptography relevant to RFID tags, smartcards, lightweight ciphers...).
Very well written and structured, this book is an excellent choice for coursebook. I used it as a textbook in crypto-course and students loved it!

An awesome book. It was easy to read, it has almost no (I actually didn't find any at all!) wrong information, and deserves its 5 star rating.