The Definitive Guide
Charles M. Kozierok
Robert B. Boatright
Illustrated by Charles M. Kozierok, Betsy Timmer, M att Holden, Colt Correa & Kyle Irving
Cover by Betsy Timmer
Designed by M att Holden
Automotive Ethernet: The Definitive Guide. Copyright © 2014 Intrepid Control Systems.
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by Bob M etcalfe, Inventor of Ethernet
Automotive Ethernet—If You Build It, They Will Come
The early Internet of 1969 ran across transcontinental trunks at 50 kilobits per
second, creating what we might dub the Kilobit Internet. Advances such as
fiber optics and dense wave-division multiplexing (DWDM) in the 1990s
brought us forward to the Megabit Internet of today. What’s next? We network
plumbers are now “gigifying” the Internet, with the Gigabit Internet promising
incredible performance beyond anything most Internet users can dream of
But what will all this power be used for?
We envision that new technologies will not only expand the Internet’s speed,
but also broaden its scope. The Internet of Things (IoT) will bring device
connectivity on a scale unimaginable even given the current Internet’s
enormous size, making good use of those gigabit connections. And another
place where I see the Internet becoming ubiquitous is in the billions of
microcontrollers used in modern automobiles, especially as we add new
safety, convenience and entertainment capabilities, and eventually move
toward driverless transportation for greater safety and efficiency.
Many people don’t realize that modern cars are already heavily networked,
and becoming more so every day. Planners foresee no fewer than four kinds of
automotive networking in the future:
1. Networking within cars, to implement systems control, driver feedback,
safety features, entertainment and many other functions.
2. Networking between cars, to implement capabilities such as collision
3. Networking between cars and the road infrastructure, for greater safety
4. Networking from cars to the Internet, to allow passengers to get driving-
related information such as maps and traffic updates in a timely manner,
or simply to remain part of our always-connected world.
Automobile networks are currently mostly focused on the first category—in-
vehicle systems—which are presently implemented using relatively slow
technologies not found outside the automotive industry. As the inner workings
of cars become more intelligent and complex, they increasingly demand
improvements in the networking area. But any new technology used here needs
to be not just faster, cheaper, and capable of connecting many nodes—it also
needs to be standardized and widely adopted, to enable compatibility and
connectivity among diverse suppliers and industries.
As I have been saying for 40 years: “If it’s networking that you need,
Ethernet is the answer; what is the question?” In this case, we there might be
consider two related questions: “What took the automotive world so long? And
how will it now use Ethernet going forward?”. This book provides the
answers to these questions.
Ethernet comprises much of the Internet’s packet plumbing, and its reach is
enormous. It has also been evolving rapidly since its invention as a personal
computer LAN back on May 22, 1973, and doing so quite successfully as a set
of open standards under IEEE Project 802. It has also been adapted from
wired to wireless in the form of Wi-Fi, also known as “wireless Ethernet”,
which will play a key role in external automotive networking in the future.
More than a billion wired and wireless (Wi-Fi) Ethernet ports now ship
annually, and the automotive industry represents the potential for this number to
This book is about Ethernet, and how its many advantages and innovations
will move in-car networking to the next level, setting the stage for a true
revolution in the capabilities of vehicles and how we use them. It provides
essential reference material for the intersection of the automotive networking
world and the Ethernet world, and points the way to the future of the connected
vehicle. It is a guide to the next big thing in the Gigabit Internet: Automotive
Inventor of Ethernet Technology
Professor of Innovation, Murchison Fellow of Free Enterprise
University of Texas at Austin