In this article, we describe a neighbour disjoint multipath (NDM) scheme that is shown to be more resilient amidst node or link failures compared to the two well-known node disjoint and edge disjoint multipath techniques. A centralised NDM was first conceptualised in our initial published work utilising the spatial diversity among multiple paths to ensure robustness against localised poor channel quality or node failures. Here, we further introduce a distributed version of our NDM algorithm adapting to the low-power and lossy network (LLN) characteristics. We implement our distributed NDM algorithm in Contiki OS on top of LOADng—a lightweight On-demand Ad hoc Distance Vector Routing protocol. We compare this implementation's performance with a standard IPv6 Routing Protocol for Low power and Lossy Networks (RPL), and also with basic LOADng, running in the Cooja simulator. Standard performance metrics such as packet delivery ratio, end-to-end latency, overhead and average routing table size are identified for the comparison. The results and observations are provided considering a few different application traffic patterns, which serve to quantify the improvements in robustness arising from NDM. The results are confirmed by experiments using a public sensor network testbed with over 100 nodes.

The commissioning of sensors and actuators within a building is often carried out by an operator who manually gathers and later inserts configuration data into the building management system. Data sets collected can easily reach hundreds which makes this manual process a slow complex operation which in turn is prone to errors. In this paper, we present a client-server architecture for a simple web based commissioning application, based on the Constrained Application Protocol (CoAP), that allows an operator to easily discover and browse through newly installed devices in order to perform commissioning configurations onsite.

This paper proposes an extension to the current IEEE802.15.4 standard in which flexible mesh networking in the low power beacon mode is enabled through the use of a distributed duty cycle management (DDCM) strategy in conjunction with a distributed time beacon scheduling (DTBS) technique. The DTBS technique enables a beacon enabled coordinator to calculate its time schedule to transmit beacons, thus avoiding potential collisions, without the need of a central coordinator. The proposed DDCM strategy is able to re-configure, in an IEEE802.15.4 beacon-enabled wireless mesh sensor network, nodes' duty cycle based only on locally available network information. DDCM features the allocation, deallocation and reallocation of superframe slots as well as the prevention and resolution of slot conflicts within a mesh network in a distributed fashion. The feasibility of our proposal is demonstrated and evaluated through network simulations. The proposed DDCM algorithm shows low slot collision probability and better energy efficiency than current state-of-the-art approaches.