IoT pushes KNX development to next level

KNX is well-known in the world of European building automation communications protocols. During the Light + Building fair this year, we talked to Joost Demarest, CTO of KNX, about the threat of cyberattacks and what role the IoT is playing in future developments. 

Cybersecurity focus

While cybersecurity was not a focus over 25 years ago when KNX was first designed, today everything is connected to the internet making it a hot topic. 

“What we have done in the past three years is updated the system so that you can design products as a manufacturer that offers authentication and or encryption. Authentication means of course that the product itself proves that it is really the sender of the message and that of course the receiver can check that. Encryption means that the useful data inside the message cannot be understood by receivers that do not have the key to decrypt the message. So we have extended our KNX twisted pair system to allow authentication and encryption. We have also extended our IP system to allow authentication and encryption,” explained Demarest.

“All of this is based on international standards,” he added. “We use AES 128, symmetric-key exchange, and we also use Diffie-Hellman, a way to exchange keys between the devices. These are all well-known encryption algorithms that are already standardized.” And on top of that, KNX data secure is already an international standard in its own right, EN50090-3-4.

IoT molding the future

KNX first became an ISO/IEC standard (ISO/IEC 14543-3-1 to 7) in 2003. Since then it has become one of the most used building automation protocols in Europe. The Internet of Things (IoT) could be a driver for the use of more open standards, and KNX hopes it will be. “We will see more networks that are more standardized,” Demarest said. “But I still think for different usage and different applications there may still be use of different protocols because one has more advantage over the other. There will still be different solutions like there are different languages, but translation between these protocols will get easier.”

In terms of integration, Demarest said, “It is difficult to integrate different solutions today because the electronics used in it are made for specific purposes, not designed to be a common network. What I think is the future is on big infrastructure but we still speak different languages, but at least the buildings can be commonly designed and everybody can use this to talk, still with specific languages.”

KNX plans to extend its current network with fully IP-based devices — devices that use web services for instance. “The KNX manufacturers want to roll out the first KNX IoT products in 2020. They will be based on the web technologies, but communicate KNX messages. For example, devices like energy storage will use KNX as a language to communicate but they use the HTTP to communicate between them,” he said.