Automotive Ethernet: The Definitive Guide Charles M. Kozierok Colt Correa Robert B. Boatright Jeffrey Quesnelle Illustrated by Charles M. Kozierok, Betsy Timmer, Matt Holden, Colt Correa & Kyle Irving Cover by Betsy Timmer Designed by Matt Holden Automotive Ethernet: The Definitive Guide. Copyright © 2014 Intrepid Control Systems. All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and publisher. Printed in the USA. ISBN-10: 0-9905388-0-X ISBN-13: 978-0-9905388-0-6 For information on distribution or bulk sales, contact Intrepid Control Systems at (586) 731-7950. You can purchase the paperback or electronic version of this book at www.intrepidcs.com or on Amazon. We’d love to hear your feedback about this book—email us at [email protected]. Product and company names mentioned in this book may be the trademarks of their respective owners. Rather than use a trademark symbol with every occurence of a trademarked name, we are using the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. The information in this book is distributed on an “As Is” basis, without warranty. While every precaution has been taken in the preparation of this book, neither the authors nor Intrepid Control Systems shall have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this book. Foreword by Bob Metcalfe, 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 today. 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: © 2014 Intrepid Control Systems. All Rights Reserved. v [email protected] • www.intrepidcs.com 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 avoidance. 3. Networking between cars and the road infrastructure, for greater safety and efficiency. 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 increase significantly. 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 Ethernet. Bob Metcalfe Inventor of Ethernet Technology Professor of Innovation, Murchison Fellow of Free Enterprise University of Texas at Austin © 2014 Intrepid Control Systems. All Rights Reserved. vi [email protected] • www.intrepidcs.com TABLE OF CONTENTS PART I: INTRODUCTION TO GENERAL AND AUTOMOTIVE NETWORKING .............. 1 Chapter 1: The Motivation for Automotive Ethernet: Advantages and Opportunities ............. 3 1.1 Introduction ............................................................................................................................................................................................... 3 1.2 Two Worlds Collide ............................................................................................................................................................................... 4 1.3 Automotive Electronics - A Market for Growth ................................................................................................................... 5 1.4 Ethernet - An Ocean of Possibilities ............................................................................................................................................ 7 1.5 Increasing Bandwidth and Future-Proof Technology ........................................................................................................... 8 1.6 Full-Duplex, Packet-Switched, Address-Based Networking ...........................................................................................10 1.6.1 Full-Duplex Operation .................................................................................................................................................................10 1.6.2 Packet Switching ..............................................................................................................................................................................11 1.6.3 Address-Based Messaging ...........................................................................................................................................................11 1.7 Electrical Isolation ................................................................................................................................................................................13 1.8 Power over Ethernet (PoE) and Power over Data Lines (PoDL) ..............................................................................14 1.9 High Speed and Low Weight ...........................................................................................................................................................15 1.10 Product Differentiation - It’s No Longer About Nuts and Bolts ................................................................................16 1.11 Wireless Functionality........................................................................................................................................................................17 1.12 Summary ....................................................................................................................................................................................................18 Chapter 2: Overview, Background and Business Requirements of Automotive Networking ..........................................................................................................................................................................19 2.1 Introduction .............................................................................................................................................................................................19 2.2 A Brief History of Automotive Networking ..........................................................................................................................20 2.2.1 The First Serial Communications ............................................................................................................................................20