Microprocessors are getting smaller, cheaper and faster. Every Day, it is easier to embed more functionality into a smaller space. Embedded processors have become pervasive, and as time goes on, more and more functions that were once implemented with analog circuitry or with electromechanical assemblies are being realized with microcontrollers, ADCs and DACs. Many of these assemblies that are being supplanted by the microprocessor are controlling dynamic processes, which is a good thing, because the microprocessor coupled with the right software is often the superior device.
Communication between various devices makes it possible to pro-
vide unique and innovative services. Although this interdevice com-
munication is a very powerful mechanism, it is also a complex and
clumsy mechanism, leading to a lot of complexity in present Day
systems. This not only makes networking difficult but also limits
its flexibility.
Over the past ten years there has been a revolution in the devel-
opment and acceptance of mobile products. In that period, cel-
lular telephony and consumer electronics have moved from the
realm of science fiction to everyDay reality. Much of that revolu-
tion is unremarkable – we use wireless, in its broadest sense, for
TV remote controls, car keyfobs, travel tickets and credit card
transactions every Day. At the same time, we have increased the
number of mobile devices that we carry around with us. However,
in many cases the design and function of these and other static
products are still constrained by the wired connections that they
use to transfer and share data.
Coverage of routing techniques in various wired and wireless networks is the unique
proposition of this book. Routing protocols and algorithms are the brains of any network.
The selection of topics in this book is clear: we attempt to explain routing in its entirety,
starting from fundamental concepts, then moving through routing on the Internet, and
finally cutting across the recent‐Day cellular, ad hoc, and wireless networks.
Recent decades have shown a tremendous expansion of the Internet. The number of
connected terminals has increased by orders of magnitude, traffic has grown exponen-
tially, coverage has become ubiquitous and worldwide, and toDay’s sophisticated Web
2.0 applications are increasingly providing services which hitherto have been the realm
of telecommunications, such as Skype and video conferencing. This has even led to the
thought that access to the Internet might one Day be a universal right of every citizen.
This evolution will accelerate in the coming decades.
Without doubt, the age of information communications is upon 11s. The rapid
pace of technological advancement in digital data communications can be wit-
nessed in a multitude of applications in our Day-to-Day existence. In recent
years, the widespread proliferation of wireless digital cornmunications hass been
readily accepted by the general population worldwide; this is nearly unpa~rallcled
in few other human scientific achievements in terms of scope and speed of devel-
opment.
The fi rst edition of this book came about because Regina Lundgren had always been
fascinated with communication. She started writing novels in the third grade. When she
was asked on her fi rst Day at the University of Washington what she hoped to do with her
degree in scientifi c and technical communication, she replied, “I want to write environ-
mental impact statements.” When Patricia Clark hired her to work at the Pacifi c Northwest
National Laboratory to do just that, she was overjoyed.
Over the past ten years there has been a revolution in the devel-
opment and acceptance of mobile products. In that period, cel-
lular telephony and consumer electronics have moved from the
realm of science fiction to everyDay reality. Much of that revolu-
tion is unremarkable – we use wireless, in its broadest sense, for
TV remote controls, car keyfobs, travel tickets and credit card
transactions every Day.
Since the first edition of the book was published, the field of modeling and simulation of
communication systems has grown and matured in many ways, and the use of simulation as a
Day-to-Day tool is now even more common practice. Many new modeling and simulation
approaches have been developed in the recent years, many more commercial simulation
packages are available, and the evolution of powerful general mathematical applications
packages has provided still more options for computer-aided design and analysis. With the
current interest in digital mobile communications, a primary area of application of modeling
and simulation is now to wireless systems of a different flavor than the traditional ones.
Battery systems for energy storage are among the most relevant technologies of the
21 st century. They – in particular modern lithium-ion batteries (LIB) – are enablers
for the market success of electric vehicles (EV) as well as for stationary energy
storage solutions for balancing fluctuations in electricity grids resulting from the
integrationofrenewableenergysourceswithvolatilesupply 1 .BothEVandstationary
storage solutions are important because they foster the transition from the usage
of fossil energy carriers towards cleaner renewable energy sources. Furthermore,
EV cause less local air pollution and noise emissions compared to conventional
combustion engine vehicles resulting in better air quality especially in urban areas.
Unfortunately, to this Day, various technological and economic challenges impede a
broad application of batteries for EV as well as for large scale energy storage and
load leveling in electricity grids.
