Most of us don't often think of updating the software in our car but this is decidedly not the case in other realms. -- software updates are becoming second nature for the 68% of Americans who have smart phones. Typically, seven to eight software updates a year have trained us to be responsive to this task. We are now familiar with plugging in our phones or using Wi-Fi when scheduling software updates and we certainly would not schedule an update when we need our phones most.
Because smart phones and tablets are so mobile and follow us everywhere, it’s easy for phone makers to send these update requests. We are compliant because we want the latest and greatest features our phones offer us and are willing to “follow the rules.” We log into our home or work Wi-Fi and, presto, our phones and tablets perform even better for us. But while we've been busy focusing on the software needs of our mobile gadgets, cars are becoming the next extension of the digital connected devices in our lives.
Our cars are morphing into living rooms on wheels. In the future, the autonomous car will have no need for windows to see or hear; the car will be made of displays with screens for maps, personalized entertainment and driving information. It will be the ultimate connected device. But the difficulty arises when we want to update our cars the same way we update phones.
The problem with updating vehicles
By 2020, there will be an estimated 50 billion connected devices and by that same year, 90% of consumer cars will be connected to the Internet. While our cars are turning into a bundle of sensors and complex technology, we cannot adopt the same method of updating our car. Connecting to Wi-Fi and waiting for downloads while our screen becomes inoperable is not an option for a car driver. Vehicles increasingly have many applications and each file will have many different characteristics and formats for updates. Separate tools will be required for various types of data.
While phones behave as if they have only one electronic control unit (ECU), cars can have more than 100 ECUs to update. Today, OEMs are moving towards over-the-air (OTA) updates via a cellular network. And with over 88.6 million cars sold worldwide just in 2015, that’s an enormous amount of data. Updating car software on the cellular network is now becoming a huge issue and worry for car makers. Should we be following the mobile phone market paradigm for updating cars?
Taking a new direction
Instead of looking to the mobile phone market, the car industry should be observing how Google Chromebooks achieve that super-fast browser experience and light touch when it comes to device updates. Google developed an efficient differential compression algorithm called Courgette in order to make Chrome software updates dramatically smaller than was previously possible. The result is faster, lower-bandwidth updates. According to the Chromium blog, Google wants smaller updates because it narrows the window of vulnerability. The company wrote that it chooses to, say, not send out a whole new 10MB update but rather use this differential algorithm in order to make the update tiny.
The idea behind this “diff” technology, as Google calls it, is creating a delta or differential between the previous version of the software and the new version it is intending to update to. The party updating the software takes an audit of what the user has on his/her connected device and just sends the new updated information. It’s like when you are food shopping, you don’t clear your pantry and purchase every new ingredient that your kitchen would ever need. Rather, you take stock of what food items you have and just buy the new fresh ingredients that week. It would be too expensive and time consuming to restock your kitchen every time you wanted to eat.
A similar solution is brewing in the car industry that is called delta compression. It takes a delta, or status of where the car software is and adapts the update according to the needs of a particular car at a particular point in time. With incremental changes to software, this concept takes what is already there and adds the differential. It can be done in a multiple file structure environment. The software updates are compressed to save even more time and bandwidth.
Thinking back to the idea of a car as a living room on wheels -- with so many applications, each file will have many different characteristics and update formats. Updates need to consider each file, the different characteristics, and take into account what incremental changes need to be downloaded and in what order. It’s obvious that compressing files and finding the delta is the way forward for the auto industry. Now that’s settled, the next question is what networks the car industry should use to transport the information? The choice is between Wi-Fi and cellular.
Not Wi-Fi, Cellular
While Wi-Fi is appealing and offers a cheap alternative to cellular, it’s cellular technology that I believe is the clear way forward for the auto industry. Why? There are a number of problems with making OTA software updates on cars using Wi-Fi. Cellular is more persuasive even though there’s a cost involved and still some bandwidth issues to be resolved. Here’s an outline of what’s at stake:
1. Size: We take our cell phones and connected devices everywhere with us, even into the bedroom, but we obviously cannot do this with cars. Cars sit in our driveway and few people have Wi-Fi systems that extend to the driveway or street outside their homes. For the many people who live in apartment blocks, Wi-Fi rarely extends to the basement where cars are parked.
2. Security: Wi-Fi is notoriously insecure and open to all kinds of security breaches. Wi-Fi is built primarily on one set of protocols. Virtually every router, access point, and wireless device is capable of using most of them. Wi-Fi standards are open and easily accessible, making Wi-Fi an easier target than cellular. On the other hand, cellular networks are varied — not only in technologies but in frequencies, too. This relates to the "honorable responsibility" of car makers to keep drivers safe, which emphasizes better network security. Car makers are spending vast sums of money to make sure the systems within cars are not breached so using Wi-Fi for transportation is akin to locking your house but leaving the keys on your front doorstep.
3. Satisfaction: Not many people plan ahead. We just get into our cars and go. We want our cars to get us where we are going without waiting 20 minutes for a download to happen before we can even turn the engine on. Having high mobility is a user requirement that will not go away. Cellular updates can be made quickly in any location.
Solution
It makes sense for the car industry and other markets such as those in the Internet of Things (IoT) to make incremental updates using adaptive delta compression. Sending so much data back and forth across the network is not sustainable in the long run for anyone. As for updating over Wi-Fi versus cellular, the car industry is sticking with cellular technology because this is the only viable option for vehicles.
Edited by
Ken Briodagh
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