TY  - JOUR
A1  - Sahlmann, Kristina
A1  - Clemens, Vera
A1  - Nowak, Michael
A1  - Schnor, Bettina
T1  - MUP
BT  - Simplifying Secure Over-The-Air Update with MQTT for Constrained IoT Devices
JF  - Sensors
N2  - Message Queuing Telemetry Transport (MQTT) is one of the dominating protocols for edge- and cloud-based Internet of Things (IoT) solutions. When a security vulnerability of an IoT device is known, it has to be fixed as soon as possible. This requires a firmware update procedure. In this paper, we propose a secure update protocol for MQTT-connected devices which ensures the freshness of the firmware, authenticates the new firmware and considers constrained devices. We show that the update protocol is easy to integrate in an MQTT-based IoT network using a semantic approach. The feasibility of our approach is demonstrated by a detailed performance analysis of our prototype implementation on a IoT device with 32 kB RAM. Thereby, we identify design issues in MQTT 5 which can help to improve the support of constrained devices.
KW  - Internet of Things
KW  - security
KW  - firmware update
KW  - MQTT
KW  - edge computing
Y1  - 2020
U6  - https://doi.org/10.3390/s21010010
SN  - 1424-8220
VL  - 21
IS  - 1
PB  - MDPI
CY  - Basel
ER  - 
TY  - GEN
A1  - Sahlmann, Kristina
A1  - Schwotzer, Thomas
T1  - Ontology-based virtual IoT devices for edge computing
T2  - Proceedings of the 8th International Conference on the Internet of Things
N2  - An IoT network may consist of hundreds heterogeneous devices. Some of them may be constrained in terms of memory, power, processing and network capacity. Manual network and service management of IoT devices are challenging. We propose a usage of an ontology for the IoT device descriptions enabling automatic network management as well as service discovery and aggregation. Our IoT architecture approach ensures interoperability using existing standards, i.e. MQTT protocol and SemanticWeb technologies. We herein introduce virtual IoT devices and their semantic framework deployed at the edge of network. As a result, virtual devices are enabled to aggregate capabilities of IoT devices, derive new services by inference, delegate requests/responses and generate events. Furthermore, they can collect and pre-process sensor data. These tasks on the edge computing overcome the shortcomings of the cloud usage regarding siloization, network bandwidth, latency and speed. We validate our proposition by implementing a virtual device on a Raspberry Pi.
KW  - Internet of Things
KW  - Edge Computing
KW  - oneM2M Ontology
KW  - M2M
KW  - Semantic Interoperability
KW  - MQTT
Y1  - 2018
SN  - 978-1-4503-6564-2
U6  - https://doi.org/10.1145/3277593.3277597
SP  - 1
EP  - 7
PB  - Association for Computing Machinery
CY  - New York
ER  -