Sharif Digital Repository

Recently, IoT has been massively applied in different areas of human life. Meanwhile, in many of the IoT applications, e.g., the remote patient health-care monitoring systems, the reliability of communications, and the consumed energy in IoT devices, which are mostly battery-operated, are very challenging. Since IoT devices are typically operated in lossy environments, providing a reliable transmission for the packets imposes a noticeable amount of energy consumption. In addition, the runtime movement of the IoT devices in mobile networks further intensifies these issues. Therefore, the applied policies in the IPv6 RPL as the standard routing mechanism in IoT networks, play an important role... 

The Internet of Things (IoT) presents a new paradigm of the future internet that intends to provide interactive communication between various processing object via heterogeneous networks. The routing protocol in the IoT environment is Routing Protocol for Low-Power and Lossy Networks (RPL). The current RPL specification defines primary security modes; therefore it is vulnerable to topological attacks. In this paper the RPL routing mechanism, its topological vulnerabilities and two important topological attacks namely version number attack and rank spoofing attack are analyzed. To counter the mentioned attacks, a lightweight Identity Based Offline–Online Signature based scheme is proposed.... 

The increasing trend in the number of smart connected devices has turned the routing procedure as one of the major challenges in IoT infrastructures. The Routing Protocol for Low Power and Lossy Networks (RPL) was introduced to satisfy different IoT application requirements through Objective Functions (OF). Although there have been several studies on introducing new OFs in order to fulfill specific IoT characteristics, e.g., energy and delay efficiency, reliability, and stability, but still there is a lack of novel OFs which fulfill the IoT application requirements in terms of both, the performance and the power consumption simultaneously. In this paper, we have proposed PEDAL, an OF which... 

The increasing trend in the number of smart connected devices has turned the routing procedure as one of the major challenges in IoT infrastructures. The Routing Protocol for Low Power and Lossy Networks (RPL) was introduced to satisfy different IoT application requirements through Objective Functions (OF). Although there have been several studies on introducing new OFs in order to fulfill specific IoT characteristics, e.g., energy and delay efficiency, reliability, and stability, but still there is a lack of novel OFs which fulfill the IoT application requirements in terms of both, the performance and the power consumption simultaneously. In this paper, we have proposed PEDAL, an OF which... 

Reliability of routing mechanisms in wireless networks is typically measured with Packet Delivery Ratio (PDR). Basically, PDR is reported with an optimistic assumption that the topology is fully constructed, and the nodes have started their packet transmission. This is despite the fact that prior to being able to transmit packets, nodes must first join the network, and then try to keep connected as much as possible. This is a key factor in the overall reliability provided by the routing protocols, especially in mobile IoT applications, where disconnections occur frequently. Nevertheless, there is a lack of appropriate metrics, which could evaluate the routing mechanisms from this... 

With the widespread use of Internet of Things (IoT) in every aspect of human's daily life, communications of such an enormous amount of existing embedded devices in these systems arise many new challenges from power consumption, performance, and reliability perspectives. Communications in an IoT infrastructure are managed by a set of policies which are determined by Objective Functions (OFs). Thus, OFs are the most important contributors in facing with the mentioned challenges. In this paper, due to the lack of information on how OFs affect the primary properties of an IoT infrastructure, we have compared three well-known OFs (OF0, MRHOF, and OFFL) from power consumption, performance, and... 

Mobile portable embedded devices are becoming an integral part of our daily activities in the vision of Internet of Things (IoT). Nevertheless, due to lack of mobility support in the IPv6 routing protocol for low-power and lossy networks (RPLs), which is standardized for multihop IoT infrastructures, providing reliable communications in terms of packet delivery ratio (PDR) in mobile IoT applications has become significantly challenging. While several studies tried to enhance the adaptability of RPL to network dynamics, their utilized routing metrics have prevented them from establishing long-lasting reliable paths. Furthermore, the stochastic parent replacement policy in the standard version...