Contiki OS

The diverse applications of the internet of things (IoT) require adaptable routing protocol able to cope with several constraints. Thus, RPL protocol was designed to meet the needs for IoT networks categorized as low power and lossy networks (LLN). RPL uses an objective function based on specific metrics for preferred parents selection through these packets are sent to root. The single routing metric issue generally doesn't satisfy all routing performance requirements, whereas some are improved others are degraded. In that purpose, we propose a hybrid objective function with empirical stability aware (HOFESA), implemented in the network layer of the embedded operating system CONTIKI, which combines linearly three weighty metrics namely hop count, RSSI and node energy consumption. Also, To remedy to frequent preferred parents changes problems caused by taking into account more than one metric, our proposal relies on static and empirical thresholds. The designed HOFESA, evaluated under COOJA emulator against Standard-RPL and EC-OF, showed a packet delivery ratio improvement, a decrease in the power consumption, the convergence time and DIO control messages as well as it gives network stability through an adequate churn. This is an open access article under the CC BY-SA license.

In this paper, we investigate how model-driven engineering (MDE) of Internet of Things (IoT) systems and Wireless-Sensor Networks (WSN) can be supported and introduce a domain-specific metamodel for modeling such systems based on the well-known Contiki operating system. The unique lightweight thread structure of Contiki makes it more preferable in the implementation of new IoT systems instead of many other existing platforms. Although some MDE approaches exist for IoT systems and WSNs, currently there is no study which addresses the modelling according to the specifications of Contiki platform. The work presented in this paper aims at filling this gap and covers the development of both a modeling language syntax and a graphical modeling environment for the MDE of IoTs according to event-driven mechanism and protothread architecture of Contiki. Use of the proposed modeling language is demonstrated with including the development of an IoT system for forest fire detection.

—Internet of Things (IoT) is envisioned as a trans-formative approach with a wide range of applications in various sectors such as home automation, industrial control, and agriculture. It promises innovative business models and improved user experience. However, as evidenced by recent attacks such as the Mirai botnet, IoT networks and systems remain very vulnerable and require stronger protection mechanisms. Furthermore, due to processing, memory, and power constraints of typical IoT devices, traditional Internet security mechanisms are not always feasible or appropriate. In this work, we are concerned with designing an Intrusion Detection System (IDS) for protecting IoT networks from external threats as well as internal compromised devices. Our proposed design adopts a signature-based intrusion detection approach and involves both certralised and distributed IDS modules. Using the Cooja simulator, we have implemented a Denial of Service (DoS) attack scenario on IoT devices. This scenario exploits the RPL protocol, which is widely used for routing in low-power networks, including IoT networks. In particular, we have implemented two variants of DoS attacks, namely " Hello " flooding and version number modification. As shown by simulation results, these attacks may impact the reachability of certain IoT devices and their power consumption.

Doubly-stochastic matrices are usually required by consensus-based distributed algorithms. We propose a simple and efficient protocol and present some guidelines for implementing doubly-stochastic combination matrices even in noisy, asynchronous and changing topology scenarios. The proposed ideas are validated with the deployment of a wireless sensor network, in which nodes run a distributed algorithm for robust estimation in the presence of nodes with faulty sensors.

Internet of Things (IoT) is already playing a significant role in our lives, as more and more industries are adopting IoT for improving existing systems and providing novel applications. However, recent attacks caused by Mirai and Chalubo botnets show that IoT systems are vulnerable and new security mechanisms are required. In this work, we design and implement a prototype of Intrusion Detection System (IDS) for protecting IoT networks and devices from Denial-of-Service (DoS) attacks. Our focus is on detecting attacks that exploit the IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL), which is a widely used protocol for packet routing in low-power IoT networks. Our considered Operating System (OS) is the popular ContikiOS and we use the Cooja simulator to study DoS attacks and test the detection algorithms. In particular, we simulated scenarios that involve both benign and malicious/compromised IoT devices. A compromised device exploits RPL control messages to cause other devices perform heavy computations and disrupt the established network routes. The obtained simulation results help us understand the characteristics of an RPL-based IoT network under its normal operation and devise effective countermeasures against malicious activity. A new threshold-based IDS is proposed and a first prototype is implemented in ContikiOS. The IDS relies on tunable parameters and involves both centralised and distributed components in order to effectively detect malicious RPL messages. Experimental results show high detection rate and low false positives in large networks.