[wsfii-discuss] Praise for the Wireless Networking Book in the Cisco Internet Protocol Journal
Patrice Riemens
patrice at xs4all.nl
Fri Aug 25 08:36:03 UTC 2006
http://www.cisco.com/web/about/ac123/ac147/archived_issues/ipj_9-2/book_review.html
The Internet Protocol Journal - Volume 9 (2006) Number 2
Book Review
Wireless Networking
Wireless Networking in the Developing World: A practical guide to planning
and building low-cost telecommunications infrastructure, by Rob Flickenger
et al., ISBN 1-4116-7837-0, 234 pages, Limehouse Book Sprint Team, January
2006. http://wndw.net
To quote from the book.s Website:
.This book was created by a team of individuals who each, in their own
field, are actively participating in the ever-expanding Internet by
pushing its reach farther than ever before. Over a period of a few months,
we have produced a complete book that documents our efforts to build
wireless networks in the developing world..
Even though I don.t live and work in what is commonly regarded as part of
the developing world, I found this to be a unique and informative book, as
its practical descriptions of wireless networking have application in many
environments.
Given the widespread availability of the raw materials of computers,
open-source software, Wi-Fi equipment, various pieces of recycled
kitchenware, scrap metal, and plastic, and a wealth of online information
resources, it is possible to construct inexpensive high-speed wireless
network systems almost anywhere these days. However, perhaps the most
visible missing component of the overall picture, but also the most
valuable, is a practical path through this wealth of information on how to
construct wireless networks, and a path that is based on the recent
experiences of others who have constructed cost-effective and practical
wireless networks in communities in the developing world. This book sets
out to meet that goal.
Organization
The book starts with a description of radio physics covering the basics of
the topic. It builds upon this a description of the typical radio design
trade-offs between information capacity and radio penetration, and
describes the commonly encountered factors of absorption, reflection,
diffraction, and interference. I found the practical approach to Fresnel
zone calculation and the description of the relationship between distance
and antenna height so well done that I was tempted to embark on the design
of a neighborhood Wi-Fi straightaway!
The chapter on network design is somewhat of a hybrid section, covering a
mix of physical layout of a wireless network and TCP/IP considerations.
There were the usual summaries of IP address structure and an introduction
to routing.
Study of the deployment of the Optimized Link State Routing (OLSR)
protocol is, however, more detailed. This is a link state routing protocol
that is open-source, supportable by Linux-based access points, and
accommodates link quality metrics into the routing protocol metric. I
found the consideration of the link budget in this section a useful
practical description of the considerations that are unique to the
wireless world, and the worked examples are excellent, together with some
useful references to online tools. This chapter is relatively dense, and
many topics are covered in a relatively short space. I suspect that an
interested reader would want to drill down further before feeling
confident enough to manage a service network, but some carefully chosen
references to further reading are there, so that the reader can follow up
this introductory material with more specialized references.
The section on antennas and transmission lines was also well-structured. I
had heard of using cylindrical cans as Wi-Fi antennas, but knew little of
the detail of how to actually do it. This book not only explains their
design, but provides a step-by-step illustrated guide to their
construction. It also provides a good description of what is involved in
outdoor installation of wireless equipment. The consideration of
commercial solutions as compared to the do-it-yourself approach was
carefully presented, as was the section devoted to security
considerations.
Aside from the technical considerations, the book also has some very
interesting case studies of wireless networking projects, and was careful
to include both success and failure stories. The issues in the developing
world about combining technical capability with practical business
solutions for communities that can be financially self-sustaining are
indeed challenging, as the case studies show. They provide not only useful
information about related experiences in setting up such network services,
but also show how such projects can be assessed in a constructive manner.
Thoughtfully Written
Having spent some time working in this area myself as part of the ISOC
Developing Countries Workshop training team, I have developed an
appreciation of what constitutes truly useful and valuable training
material, and this book is perhaps the best example I.ve seen yet. It is
practical, helpful, technically accurate, and relatively complete in terms
of coverage of material. Where the book does not dive into fine detail it
provides useful references for further reading. The book is thoughtfully
written in a simple non-nonsense style and does not hide behind technical
jargon. Above all, it is material that can instill confidence that these
networks can readily be built and operated by people like you and me.
I certainly would not call myself an expert after reading this book, but
the next time a radio technician arrives in the office and starts talking
about radiation patterns, front-to-back ratios, and the relative merits of
omnis and yagis, at least I.ll have an idea of what he is talking about.
Even better, I might even be able to show him my own modest efforts in
do-it-yourself Wi-Fi networking by then!
Review by
Geoff Huston, APNIC
gih at apnic.net
More information about the wsfii-discuss
mailing list