Performance Comparison of the RPL and LOADng Routing Protocols in a Home Automation Scenario

RPL, the routing protocol proposed by IETF for IPv6/6LoWPAN Low Power and Lossy Networks has significant complexity. Another protocol called LOADng, a lightweight variant of AODV, emerges as an alternative solution. In this paper, we compare the performance of the two protocols in a Home Automation scenario with heterogenous traffic patterns including a mix of multipoint-to-point and point-to-multipoint routes in realistic dense non-uniform network topologies. We use Contiki OS and Cooja simulator to evaluate the behavior of the ContikiRPL implementation and a basic non-optimized implementation of LOADng. Unlike previous studies, our results show that RPL provides shorter delays, less control overhead, and requires less memory than LOADng. Nevertheless, enhancing LOADng with more efficient flooding and a better route storage algorithm may improve its performance

IETF standardization in the field of the Internet of Things (IoT): a survey

Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities

Comparative Study of RPL-Enabled Optimized Broadcast in Wireless Sensor Networks

Recent trends have suggested convergence to Wireless Sensor Net- works (WSNs) becoming IPv6-based. To this effect, the Internet Engineering Task Force has chartered a Working Group to develop a routing protocol specification, enabling IPv6-based multi-hop WSNs. The current effort of this working group is development of a unicast routing protocol denoted RPL. RPL constructs a “DAG-like” logical structure with a single root, at which the majority of the traffic flows terminate, and assumes restrictions on network dynamics and traffic generality, in order to satisfy strict constraints on router state and processing. This memorandum investigates the efficient network-wide broadcast mechanisms in WSNs, using the logical structure already established by RPL. The aim hereof is to impose minimal additional state requirements on WSN routers, beyond that already maintained by RPL. This memorandum presents a selection of such broadcast mechanisms for RPL routed WSNs, and evaluates their performances. As part of this evaluation, the memorandum compares with MPR Flooding – an established efficient flooding optimization, widely used in MANETs.Les tendances récentes suggèrent une convergence des réseaux de capteurs sans fils (WSNs ou Wireless Sensor Networks) vers IPv6. C'est pourquoi l'IETF (Internet Engineering Task Force) a mis en place un groupe de travail, chargé de spécifier un protocole de routage permettant aux réseaux de capteurs sans fil multi-sauts de fonctionner avec IPv6. Les efforts du groupe de travail se concentrent actuellement sur le développement d'un protocole de routage unicast appelé RPL. RPL construit une architecture logique de type DAG (graphe orienté acyclique) avec un noeud racine unique sur lequel se termine la majorité des flux de trafic, et suppose des restrictions sur les dynamiques du réseau et sur les types de trafic supportés afin de satisfaire les contraintes fortes des routeurs en terme d'états et de traitement. Cet article examine la possibilité de fournir aux réseaux de capteurs sans fil des mécanismes efficaces de broadcast (diffusion), en utilisant la structure logique déjà proposée par RPL. Le but est ici de ne pas imposer d'exigences supplémentaires aux routeurs WSN fonctionnant déjà avec RPL. De tels mécanismes de broadcast pour les réseaux WSN utilisant le routage RPL, l'article en présente plusieurs et évalue leur performance. Dans le cadre de cette évaluation, ils sont comparés aux mécanismes reconnus et efficaces d'optimisation de diffusion du protocole MPR Flooding, largement utilisé dans les réseaux MANETs

A Comparative Performance Study of the Routing Protocols LOAD and RPL with Bi-Directional Traffic in Low-power and Lossy Networks (LLN)

Routing protocols for sensor networks are often designed with explicit assumptions, serving to simplify design and reduce the necessary energy, processing and communications requirements. Different protocols make different assumptions -- and this memorandum carefully considers those made by the designers of RPL -- an IPv6 routing protocol for such networks, developed within the IETF. Specific attention is given to the predominance of bi-directional traffic flows in a large class of sensor networks, and this memorandum therefore studies the performance of RPL for such flows. As a point of comparison, a different protocol, called LOAD, is also studied. LOAD is derived from AODV and supports more general kinds of traffic flows. The results of this investigation reveal that for scenarios where bi-directional traffic flows are predominant, LOAD provides similar data delivery ratios as RPL, while incurring less overhead and being simultaneously less constrained in the types of topologies supported

A Test Bed for Evaluating the Performance of IoT Networks

The use of smaller, personal IoT networks has increased over the past several years. These devices demand a lot of resources but only have limited access. To establish and sustain a flexible network connection, 6LoWPAN with RPL protocol is commonly used. While RPL provides a low-cost solution for connection, it lacks load balancing mechanisms. Improvements in OF load balancing can be implemented to strengthen network stability. This paper proposes a test bed configuration to show the toll of frequent parent switching on 6LoWPAN. Contiki’s RPL 6LoWPAN software runs on STM32 Nucleo microcontrollers with expansion boards for this test bed. The configuration tests frequency of parent changes and packet loss to demonstrate network instability of different RPL OFs. Tests on MRHOF for RPL were executed to confirm the working configuration. Results, with troubleshooting and improvements, show a working bed. The laid-out configuration provides a means for testing network stability in IoT networks