"Modern Cryptography: Theory and Practice", Wenbo Mao, 2004,

0-13-066943-1, U$54.99/C$82.99

%A Wenbo Mao

%C One Lake St., Upper Saddle River, NJ 07458

%D 2004

%G 0-13-066943-1

%I Prentice Hall

%O U$54.99/C$82.99 +1-201-236-7139 fax: +1-201-236-7131

%O http://www.amazon.com/exec/obidos/ASIN/0130669431/robsladesinterne

http://www.amazon.co.uk/exec/obidos/ASIN/0130669431/robsladesinte-21

%O http://www.amazon.ca/exec/obidos/ASIN/0130669431/robsladesin03-20

%O tl s rl 1 tc 3 ta 3 tv 0 wq 1

%P 707 p.

%T "Modern Cryptography: Theory and Practice"

A "Short Description of the Book" states that it is intended to

address the issue of whether various crypto algorithms are

"practical," as opposed to just theoretically strong. This seems odd,

since no algorithm is ready for implementation as such: it must be

made part of a full system, and most problems with cryptography come

in the implementation. The preface doesn't make things much clearer:

it reiterates a "fit-for-application" mantra, but doesn't say clearly,

at any point, why existing algorithms are not appropriate for use.

The preface also suggests that this book is for advanced study in

cryptography, although it states that security engineers and

administrators, with special responsibility for developing or

implementing cryptography, are also in the target audience.

Part one is an introduction, consisting of two chapters. Chapter one

outlines the idea of the first "protocol" of the book: a "fair coin

toss" over the telephone, grounding the book firmly in the camp of

cryptography for the purpose of secure communications. The remainder

of the chapter points out all the requirements to make such an

unbiased selector work, acting as a kind of sales pitch or "come on"

to make you want to read the rest of the book. The promotion is

slightly flawed by the fact that there is very little practical detail

in the material (it takes a lot of work on the part of the reader to

figure out that, yes, this system might work), excessive verbiage, and

poor explanations. The stated "objectives" of the chapter, given at

the end, say that you should have a "fundamental understanding of

cryptography": this is true only in the most limited sense. Chapter

two slowly builds a kind of pseudo-Kerberos system.

Part two covers mathematical foundations. Chapter three deals with

probability and information theory, four with Turing Machines and the

notion of computational complexity, five with the algebraic

foundations behind the use of prime numbers and elliptic curves for

cryptography, and various number theory topics are touched on in

chapter six.

Part three addresses basic cryptographic techniques. Chapter seven

deals with basic symmetric encryption techniques, touching on

substitution and transposition, as well as reviewing the operations of

DES (Data Encryption Standard) and AES (Advanced Encryption Standard).

The insistence on converting all operations, and giving all

explanations, in symbolic logic does not seem to have any utility,

does not provide any clarity, and makes the material much more

difficult than it could be. Asymmetric techniques, and attacks

against them, are outlined in chapter eight. Finding individual bits

of the message, a process examined in chapter nine, can, over time,

result in an attack on the message or key as a whole. Chapter ten

looks at data integrity, hashes, and digital signatures.

Part four deals with authentication. Chapter eleven reviews various

conceptual protocols, pointing out (for example) that there is a

serious problem of key storage for challenge/response systems. A

variety of real applications are considered in chapter twelve, and

warnings issued about each. Issues of authentication specific to

asymmetric systems are covered in chapter thirteen.

Part five looks at formal approaches to the establishment of security.

There is more asymmetric cryptographic theory in chapter fourteen.

Chapter fifteen examines a number of provably secure asymmetric

cryptosystems, while sixteen does the same for digital signatures.

Formal methods of authentication protocol analysis are given in

chapter seventeen.

Part six discusses abstract cryptographic protocols. Chapter eighteen

reviews a number of zero knowledge protocols, which provide the basis

for authentication where the principals are not previously known to

each other. The coin flipping protocol, initiated in chapter one, is

revisited in chapter nineteen. Chapter twenty wraps up with a summary

of the author's intentions for the book.

The book is certainly for advanced study, but it is hardly suitable

for security administrators, professionals, or even engineers. The

mathematical material is quite demanding, and is seldom explained (as

opposed to the clear explanations of the implications of the math that

is given in, for example, "Applied Cryptography" [cf. BKAPCRYP.RVW],

or even the equally advanced but much more comprehensible "Algebraic

Aspects of Cryptography" [cf. BKALASCR.RVW]). However, there are

points in the material that could be useful for practical

cryptographic systems, provided one is dealing primarily with

authentication of communications, and the possibility of physical

access is ignored. The text would have been much more useful if the

author could have been induced to provide some of the basic

explanations in English, rather than leaving the reader to work out

the math.

copyright Robert M. Slade, 2004 BKMDNCRP.RVW 20041207

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Security is difficult, President. Anyone who says differently is

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http://victoria.tc.ca/techrev or http://sun.soci.niu.edu/~rslade