15 research outputs found
Experimental Evaluation of Empirical NB-IoT Propagation Modelling in a Deep-Indoor Scenario
Path-loss modelling in deep-indoor scenarios is a difficult task. On one
hand, the theoretical formulae solely dependent on transmitter-receiver
distance are too simple; on the other hand, discovering all significant factors
affecting the loss of signal power in a given situation may often be
infeasible. In this paper, we experimentally investigate the influence of
deep-indoor features such as indoor depth, indoor distance and distance to the
closest tunnel corridor and the effect on received power using NB-IoT. We
describe a measurement campaign performed in a system of long underground
tunnels, and we analyse linear regression models involving the engineered
features. We show that the current empirical models for NB-IoT signal
attenuation are inaccurate in a deep-indoor scenario. We observe that 1) indoor
distance and penetration depth do not explain the signal attenuation well and
increase the error of the prediction by 2-12 dB using existing models, and 2) a
promising feature of average distance to the nearest corridor is identified.Comment: 6 pages, 6 figures, submitted to Globecom2020 conference, Selected
Areas in Communications Symposium, Track on Internet of Things and Smart
Connected Communitie
Performance Evaluation of Group OSCORE for Secure Group Communication in the Internet of Things
The Constrained Application Protocol (CoAP) is a major application-layer protocol for the Internet of Things (IoT). The recently standardized security protocol Object Security for Constrained RESTful Environments (OSCORE) efficiently provides end-to-end security of CoAP messages at the application layer, also in the presence of untrusted intermediaries. At the same time, CoAP supports one-to-many communication, targeting use cases such as smart lighting and building automation, firmware update, or emergency broadcast. Securing group communication for CoAP has additional challenges. It can be done using the novel Group Object Security for Constrained RESTful Environments (Group OSCORE) security protocol, which fulfills the same security requirements of OSCORE in group communication environments. While evaluations of OSCORE are available, no studies exist on the performance of Group OSCORE on resource-constrained IoT devices. This article presents the results of our extensive performance evaluation of Group OSCORE over two popular constrained IoT platforms, namely Zolertia Zoul and TI Simplelink. We have implemented Group OSCORE for the Contiki-NG operating system and made our implementation available as open source software. We compared Group OSCORE against unprotected CoAP as well as OSCORE. To the best of our knowledge, this is the first comprehensive and experimental evaluation of Group OSCORE over real constrained IoT devices
Performance Evaluation of Group OSCORE for Secure Group Communication in the Internet of Things
The Constrained Application Protocol (CoAP) is a major application-layer protocol for the Internet of Things (IoT). The recently standardized security protocol Object Security for Constrained RESTful Environments (OSCORE) efficiently provides end-to-end security of CoAP messages at the application layer, also in the presence of untrusted intermediaries. At the same time, CoAP supports one-to-many communication, targeting use cases such as smart lighting and building automation, firmware update, or emergency broadcast. Securing group communication for CoAP has additional challenges. It can be done using the novel Group Object Security for Constrained RESTful Environments (Group OSCORE) security protocol, which fulfills the same security requirements of OSCORE in group communication environments. While evaluations of OSCORE are available, no studies exist on the performance of Group OSCORE on resource-constrained IoT devices. This article presents the results of our extensive performance evaluation of Group OSCORE over two popular constrained IoT platforms, namely Zolertia Zoul and TI Simplelink. We have implemented Group OSCORE for the Contiki-NG operating system and made our implementation available as open source software. We compared Group OSCORE against unprotected CoAP as well as OSCORE. To the best of our knowledge, this is the first comprehensive and experimental evaluation of Group OSCORE over real constrained IoT devices