CAN and the Internet of Things

To bring CAN nodes into the IoT world, we need to make them talking to other things.

By Holger Zeltwanger (CAN in Automation) August 22, 2014

Everyone talks about the Internet of Things, abbreviated IoT. But the term is not used uniformly. The IoT concept is quite unclear, as if you look through a rain-spotted windshield. In order to bring CAN nodes into the IoT world, we need to make them talking to other Things.

Kevin Ashton invented the term Internet of Things (IoT). In a quote from an article in the RFID Journal 1999, he stated: "If we had computers that knew everything there was to know about things – using data they gathered without any help from us – we would be able to track and count everything, and greatly reduce waste, loss and cost. We would know when things needed replacing, repairing or recalling, and whether they were fresh or past their best."

This extends the definition of the first version of the Internet: It was all about data created by people. The IoT is about data created by things. Most of us think about being connected in terms of computers, tablets and smartphones. IoT describes a world where just about anything can be connected and is able to communicate to each other. In other words, with the IoT, the physical world is becoming one big information system.

Wikipedia defines IoT as an interconnection of uniquely identifiable embedded computing like devices within the existing Internet infrastructure: "Typically, IoT is expected to offer advanced connectivity of devices, systems, and services that goes beyond machine-to-machine (M2M) communications and covers a variety of protocols, domains, and applications. The interconnection of these embedded devices (including smart objects), is expected to usher in automation in nearly all fields, while also enabling advanced applications like a Smart Grid."

Things, in the IoT, can refer to a wide variety of devices such as heart monitoring implants, biochip transponders on farm animals, road vehicles with built-in sensors, or field operation devices that assist fire-fighters in search and rescue. Current market examples include smart thermostats such as the nest and washer/dryers that utilize WiFi for remote monitoring (Source: Wikipedia).

Technopedia regards IoT as a computing concept that describes a future, in which everyday physical objects will be connected to the Internet and be able to identify themselves to other devices: "The term is closely identified with RFID as the method of communication, although it also may include other sensor technologies, wireless technologies or QR codes." In this understanding an object can represent itself digitally. It becomes something greater than the object by itself. No longer does the object relate just to you, but is now connected to surrounding objects and database data. When many objects act in unison, they are known as having "ambient intelligence."

This is known for more than 2000 years: "The whole is greater than the sum of its parts" (Aristotle). Due to the ubiquitous nature of connected objects in the IoT, an unprecedented number of devices is expected to be connected to the Internet. According to Gartner, there will be nearly 26 billion devices on the IoT by 2020. ABI Research estimates that more than 30 billion devices will be wirelessly connected to the IoT by 2020. Per a recent survey and study done by Pew Research Internet Project, a large majority of the technology experts and engaged Internet users who responded-83 percent-agreed with the notion that the IoT and embedded and wearable computing will have widespread and beneficial effects by 2025. It is, as such, clear that the IoT will consist of a very large number of devices being connected to the Internet. In 2008, the number of things connected to the Internet exceeded already the number of people on earth. Cisco forecasts 50 billion things by 2020. Imagine that all of these things can communicate and respond to one another assuming that they are related in some way. This concept is a challenge for all makers of things.

More than one billion CAN nodes per year

Many of these things are deeply embedded and CAN connected: in passenger cars, industrial machines, HVAC systems, medical devices, etc. There are sold annually about one billion CAN interfaces. They all have the potential to be connected to the Internet meaning to other things. If your home’s heating system, for example, uses embedded CAN networks, it will keep the optimal temperature, because the CAN-connected thermostat might adjust itself based on the weather forecast data received via Internet. And there are more examples like this.

ODVA, the DeviceNet user organization, and CiA, the CAN users’ and manufacturers’ group, have started IoT special interest groups (SIG) to make CAN-connectable devices to things of the Internet. ODVA’s SIG "DeviceNet of Things" scope of work is to develop enhancements to specifications that will enable expanded adoption of DeviceNet to low cost, simple industrial devices. By extending DeviceNet to more types of devices, users will be able both to preserve their investment and to enable connectivity with Ethernet/IP via ODVA’s Common Industrial Protocol (CIP). To achieve its business objectives to lower connectivity costs for simple, less expensive devices and to promote ease of use for network installation and commissioning, the initial phase of the SIG’s work will focus on development of an IP20-rated physical layer connection system that reduces device connection cost and installation time, an auto addressing scheme that eliminates the need to set node addresses, and visibility in devices that until now have not had the ability to provide diagnostics.

A future phase of work will focus on enhancements for an IP67-rated physical layer connection system. In 2015, the organization expects the DeviceNet specification to include enhancements from the first phase of work, with products following shortly after publication of the enhancements within the specification. "The Internet of Things movement has established a basis for innovation of new smart "things" in the automation world, but the cost of Ethernet is still too high for many industrial "things" or devices," said Katherine Voss, president and executive director of ODVA. "Users will be provided with the unparalleled business benefit of cost-competitive connectivity today for devices previously not connected, as well as systems engineered for the future that can evolve in step with the Internet of Things as the costs of Ethernet continue to decline."

The SIG held its first meeting in conjunction with the organization’s 2014 Industry Conference and 16th annual meeting of members. As of the first meeting, six ODVA members had signed up to participate in the SIG, including Eaton Electrical, HMS Industrial Networks, Omron, Panduit, Rockwell Automation, and Weidmueller Interface.

CiA’s SIG "Internet of Things" likes to introduce a more function-oriented service/way of communication. The participating parties are in favor of providing a "pool of harmonized functions". From anywhere in the CANopen system, such a pool of functions is accessible and independent of the hardware platform and communication technique, the "user" could rely on the harmonized functionality. To run such a system, CANopen would require not only an addressing by node-IDs and (sub-)indexes, but in addition a functional addressing without knowing the node-ID. Furthermore the CANopen SIG IoT experts have in mind to offer an enhanced, harmonized visualization so that any CANopen device is able to determine the way its parameters/attributes are displayed on any HMI (e.g. terminal, tablet, cell phone, remote desktop, etc.).

One of the use cases is maintenance and service. The CANopen devices introduce themselves to each other and learn about the neighbors’ functionality. This means, it doesn’t matter, where you access the network system. The user has always access to all functionality in the entire system. There could be multiple access points for the service technician. Besides monitoring and diagnosing the network system, you can also control the system by means of the provided mechanisms.

The required functional addressing doesn’t rely anymore on network-IDs and node-IDs. The end-user or Things can request or command some actions as well as demand status information from the individual CANopen functions, wherever they are physically installed. For this purpose, generic function codes need to be standardized. Functions should be also able to return information. This allows an automatic monitoring of functional progress and operational results. Functional addressing is intended to call functions e.g. from an end-user’s mobile phone. CANopen network access services as provided in CiA 309-1 should be available to certain extend as callable functions.

Besides the home and building automation industry, also the manufacturers of mobile working machines are interested in CANopen IoT solutions. Other industries will follow, when IoT becomes a requirement in the related application fields. In particular, industrial automation and embedded machine control systems may have an interest in these IoT activities. But first of all, they have to identify use cases.

Standardization is required

Although there are standards related or relevant to IoT components, devices, and sub-systems (e.g., sensor networks, smart sensors/transducers, RFID, protocols, wireless, various types of wired and wireless networks, etc.), there presently do not exist dedicated and practical standards to guide IoT systems development and implementation while the domain applications/services developers are moving forward in developing and implementing IoT Systems without IoT guiding standards.

There are some initial IoT related reference models/architectures/frameworks such as IoT-A, ITU-T, ISO/IEC 29182, IoT @Work, One M2M, Future Network, Internet of Things Initiative, GS1 EPCglobal etc. But they are not harmonized. China has submitted a new work item proposal (NWIP) to ISO/IEC to standardize an IoT Reference Architecture, which failed in the first attempt. It has been modified and was re-submitted recently. The scope reads as follows: "This International Standard specifies not only IoT conceptual model by identifying and defining the IoT domains but also IoT reference architecture from various architectural views/perspectives by detailing the model with identifying each IoT domain’s entities and defining high-level inter- and intra-domain interfaces among the domain entities."

Within the CAN community, ODVA and CiA are the first associations, which have started to think about IoT use cases and solutions for CAN-based systems. Also the automotive industry has started OEM-specific IoT projects, e.g. to connect the car via Internet to the infrastructure, which may provide weather and other information to the advanced driver assistant systems (ADAS). Some of these automotive use cases are already reported in the CAN Newsletter Online ( The keyword is (semi-)autonomous driving.

For factory and process automation as well as industrial machine control IoT use cases need to be developed. One example is the connection to a logistic system for spare parts: so that devices for replacement are ordered automatically before the expiration dates. Another example is the connection to other machines of the same kind to detect problems and possible malfunctions as early as possible. And there are more use cases to invent.

The IoT has also another side: unauthorized access by "bad" boys. No doubt, IoT carries the potential for catastrophe. Security is a severe problem and not yet solved – even not really discussed. You will not like that antivirus programs run on your car or you will not like to update software frequently in all your IoT devices. If it is done via the Internet, it may cause additional security issues. Firewalls are just as good as the software is written. And there is no failure-free software.

– Edited by Anisa Samarxhiu, Digitial Project Manager, CFE Media,