Linux and the Internet of Things.

I wake up in the middle of the night, mouth parched and vision blurry, and fumble around to find my iPhone. I press my thumb to the fingerprint scanner, and in the dim blue light, just out of instinct, I squint at the screen, find the right app, open it, and check the ambient temperature and air quality indoors. It turns out my goose bumps are lying; the temperature is quite comfortable and not arctic-level freezing, which is how it feels to me. Now, I touch a virtual switch, and warm yellow light illuminates my way to the kitchen. I slowly waddle towards the water bottle without stumbling over one of my cats, have a drink, and safely waddle back to bed. Another tap on my app screen, and the light fades away; I sleep.

This is my reality, and an increasingly common one in many people's homes. The only difference? My tech is mostly self-made—with few exceptions, of course.

Our homes slowly but surely fill up with small, smart gadgets that make our control over our surroundings stronger and more precise. These are the tools that help us create customizable, responsive home environments that anticipate our needs and intelligently adapt to our rhythms. Perhaps these gadgets even make us a little spoiled, but mostly, they help us feel comfortable in and educated about our environments. Never before have we known so much in precisely quantified units about our living spaces, working spaces and ourselves. Smart homes tell us about the air we breathe, the water we drink, and the temperature and humidity in which we live, and vigilantly guard us from strangers or threats. They have become an extension of ourselves in the best possible way, automating important but mundane tasks so we can focus on more important things, like maintaining the late-night cat/human detente.

The Four Factors That Led to IoT

What are the circumstances that allowed this wonderful reality to materialize? From my perspective, I think of four factors as being largely responsible:

1. Tiny, inexpensive, power-efficient-yet-powerful processors replacing older, simpler microcontrollers.
2. Cloud processing becoming cheap enough to be accessible and affordable for large and small companies alike.
3. Smartphones becoming powerful multicore computers that are practically ubiquitous.
4. Linux making it remarkably easy to spin up a smart application that can run on anything from toaster to a spaceship with minimal effort, and that same Linux OS powering the back-end cloud side.

Let's flesh this out a little more.

Microcontrollers:

Silicone vendors have improved manufacturing technologies so much that each transistor in a processor is now imperceptibly tiny (14 nanometer technology!). They bring magic to life with their new lines of low-powered systems on chips (SOCs) and have brought the market to the point where a chip the size of a small postage stamp costs $2–$7 and still has:

• A full hardware network stack (that is, a built-in capability to connect to the Internet).
• A dual-core ARM family processor.
• Enough computation power to run an operating system.
• Plenty of other useful features that all run off a single coin cell battery.

All you have to do is stick it in a package—a watch, a small gadget on the wall, a light bulb, or whatever your company desires—and you instantly "smartify" your product. This kind of luxury (which wasn't available even a decade ago) has driven companies to opt for the use of true operating systems on their devices (namely Linux) and to forgo the older, more difficult and less efficient path of direct microcontroller programming with a single "forever" loop and every software aspect done in-house.

The Cloud:

At the same time, organizations like Amazon are offering their cloud infrastructures to anyone for reasonable costs. This enables companies to wield unimaginable computational power—still running Linux, mind you—without investing anything in the purchase, physical installation or maintenance of the hundreds of powerful processing machines at their disposal. A company of two people can bring distributed services to its customers that require intensive computational power; this would have been a complete deal-breaker (even for large companies) in the pre-cloud era.

Smartphones:

There is not much to be added about the role of smartphones in the "smartification" of our environment. As a society, we quickly adapted to the beautiful, intuitive control interfaces and quick response times, and they've become so much a part of our daily lives that parting with one, even just for a few hours, causes most people to feel naked. What many people do not realize, however, is the vast computational power in each and every modern smartphone. Just to bring a few personal reference points into the picture:

• 1993: my first computer was an Intel 386 40MHz with a whopping 8MB of RAM, 170MB of hard drive storage and a 1MB graphics accelerator.
• 2015: my smartphone, a Samsung Galaxy, has a Qualcomm Snapdragon with a quad-core 2.5GHz processor, 2GB of RAM, and 32GB of fast Flash storage and a 32 pipeline 3D hardware graphic accelerator.

To review, just looking at CPU speed and quantity of cores, my phone has roughly 250 times more computation power than my desktop did. I'm not even taking into account the so-very-useful additional features that every phone packs nowadays—portability, elegant UI, constant connectivity and precise sensors like GPS, accelerometers, gyroscopes, magnetic compasses, ambient light sensors and megapixel/HD cameras. All of those factors are pure gold for making our environment smart and creating IoT concepts.

Linux:

Linux is the final component that makes the Internet of Things a reality—the glue that holds everything together. How, you ask? Well, let's look at a typical product and try to understand how Linux contributes to and affects each step of development.

Let's start with the end point—the wearable or home-based gadget. It usually hides either a high- or low-end ARM-based SOC inside it. (Considering that even low-end microcontrollers are capable of running a small operating system, it's safe to assume this one could as well.) Now, as a company, what sounds easier: a) building an original software environment from scratch that includes task scheduling, memory management, peripherals access that supports multiple technologies (for example, I2C, SPI, SDIO and so on) and creating your own implementation of a network stack, including various cryptology solutions to support secure socket layer (SSL, the almost omnipresent secure communication standard over the Internet); or b) taking a free, constantly evolving and improving operating system tested by billions that provides all of those things and more? Obviously, b is the clear winner.

The Rise of Linux

Through the years, Linux has become such a complete solution that you would need to find an incredibly convincing argument to choose an alternate approach to a hardware OS. Not only is the Linux kernel versatile and easy to tweak and adjust to fit the needs of a project exactly, but it's also cross-compilation-friendly; Linux can be brought to almost any given platform, and as operating systems go, it can be very low maintenance in terms of hardware resources. This is an operating system internally built to support almost any imaginable hardware layout or peripheral, and while it's not completely plug-and-play and certainly requires an investment of labor, it comes ready for such work and aims to make it as easy as possible.

Let's move on to the next part of the chain—the cloud, where the power of Linux manifests itself from a different angle. Now, ideally, we want an operating system that is capable of managing vast computation power, many processors on one machine, high-throughput network stack, and if you don't mind, could you please throw in off-the-shelf powerful solutions for different aspects of the cloud infrastructure? Oh, and could you also make it all free? Yes, it's all that—your operating system is that same Linux, but this time, it's tweaked to answer your server-side demands, most of the additional components any company needs (such as message queues, caching, Web servers, databases and so on) and comes at no cost thanks to the Open Source community. This is mind-bogglingly wonderful.

The last part is the smartphone. Here, it gets a little trickier—how are an Android or iOS phone, an Internet of Things solution, and Linux all connected? Indeed, the link is a less obvious one. (And as a tangent, let's quickly call out that Android is, in fact, Linux! It's the same old Linux with a little polish on top known as the Android services layer.)

The main thing is that Linux has developed a wide, Open Source community that creates and maintains the various infrastructure solutions (like the ones mentioned above), and these same solutions get adjusted and ported to work in the mobile environment as well. To that end, even if Linux itself does not necessarily run on the mobile phone, its derivatives and side products often are present, simplifying the process of integrating the smartphone as part of the Internet of Things ecosystem.