IoT Security


Interconnecting embedded devices with the Internet leads to the so-called Internet of things (IoT). The Internet of things is envisioned to realize fascinating applications, such as smart cities, predictive maintenance, and precision agriculture. These applications will involve large numbers of embedded devices that communicate with each other and remote hosts.

The security challenges in this area are diverse. On the one hand, IoT devices can be attacked from the Internet. On the other hand, IoT devices are often deployed outdoors in hostile environments and communicate wirelessly. Consequently, IoT devices require protection from both remote and local attackers.

Our research in this area currently focusses on preventing denial-of-sleep attacks. Such attacks aim to drain the energy reserves of battery-powered and energy-harvesting IoT devices.


We provide a denial-of-sleep-resilient MAC layer for the IoT operating system Contiki-NG. The newest version of our MAC layer is based on the standardized MAC protocol coordinated sampled listening (CSL).


  • Denial-of-Sleep-Resilient Session Key Establishment for IEEE 802.15.4 Security: From Adaptive to Responsive. Krentz, Konrad-Felix; Meinel, Christoph; Graupner, Hendrik (2018).
  • More Lightweight, yet Stronger 802.15.4 Security through an Intra-Layer Optimization. Krentz, Konrad-Felix; Meinel, Christoph; Graupner, Hendrik (2017).
  • Secure Self-Seeding with Power-Up SRAM States. Krentz, Konrad-Felix; Meinel, Christoph; Graupner, Hendrik (2017).
  • Countering Three Denial-of-Sleep Attacks on ContikiMAC. Krentz, Konrad-Felix; Meinel, Christoph; Graupner, Hendrik (2017).
  • Demo: Enabling En-Route Filtering for End-to-End Encrypted CoAP Messages. Seitz, Klara; Serth, Sebastian; Krentz, Konrad-Felix; Meinel, Christoph (2017).
  • POTR: Practical On-the-fly Rejection of Injected and Replayed 802.15.4 Frames. Krentz, Konrad-Felix; Meinel, Christoph; Schnjakin, Maxim (2016).
  • Handling Reboots and Mobility in 802.15.4 Security. Krentz, Konrad-Felix; Meinel, Christoph (2015).
  • 6LoWPAN Security: Adding Compromise Resilience to the 802.15.4 Security Sublayer. Krentz, Konrad-Felix; Rafiee, Hosnieh; Meinel, Christoph (2013).