Section: New Results

RFID and Internet of Things

Participants : Roudy Dagher, Nathalie Mitton, Roberto Quilez, Loic Schmidt, David Simplot-Ryl, Lei Zhang.

Reader anti-collision protocol

In a Radio-Frequency IDentification network, while several readers are placed close together to improve coverage and consequently read rate, reader-reader collision problems happen frequently and inevitably. High probability of collision not only impairs the benefit of multi-reader deployment, but also results in misreadings in moving RFID tags. In order to eliminate or reduce reader collisions, we propose in [28] an Adaptive Color based Reader Anti-collision Scheduling algorithm (ACoRAS) for $13.56$ MHz RFID technology where every reader is assigned a set of colors that allows it to read tags during a specific time slot within a time frame. Only the reader holding a color (token) can read at a time. Due to application constraints, the number of available colors should be limited, a perfect coloring scheme is not always feasible. ACoRAS tries to assign colors in such a way that overlapping areas at a given time are reduced. To the best of our knowledge ACoRAS is the first reader anti-collision algorithm which considers, within its design, both application and hardware requirements in reading tags. We show, through extensive simulations, that ACoRAS outperforms several anticollision methods and detects more than $99\%$ of mobile tags while fitting application requirements.

Distributed ALE

Following the Internet of Things concept [14] , each object is associated with a unique identifier which will allow to retrieve information about it in large databases. In the process of managing a large amount of objects, and consequently a large amount of events from readers, without overloading the network, these events have to be filtered and aggregated. This is the aim of the Application Level Events (ALE) standard from EPCGlobal, which receives events from readers and sends a useful and well constructed report to the business application. The ALE may be connected to several hundreds of readers. As the number of readers may increase with the increase of the company, a bottleneck may appear with all readers events sent to the ALE. A solution for scalability is to distribute the ALE. In [37] , we propose an efficient way to solve this problem based on a Distributed Hash table (DHT). One role of the ALE is to insulate business application from technical concern so in our solution, we present a mechanism to distribute the ALE using Chord, a well-known peer-to-peer lookup system, and being transparent for business applications. This solution is compliant with the EPCglobal existing standard, scalable, robust and transparent for other layers of the middleware. We show that our solution generates only $10\%$ overhead than in a nominal case while offering a better robustness and scalability when numbers of tags and readers increase significantly.

Advance Internet of Things

The Internet of Things (IoT) is a network of Internet-enabled objects, whose original purpose would be to interconnect all things in our daily life to build an always connected world. However, most of studies in the current IoT scientific community only focus on the radio-frequency identification (RFID) and wireless sensor network (WSN) based objects and lose the generality features endowed by the original definition of IoT. Furthermore, the emergence and proliferation of smart objects have been significantly changing our daily lives. It has been becoming evident that the objects should far beyond only "be identified and interconnected", but can also be controlled in an intelligent and transparent way independent of third party object (user) profiles and space and time span. In [39] , we proposes a standardization scheme for a new paradigm: Advanced Internet of Things (AIoT), which is based on our proposed Unified Object Description Language (UODL) and allows to identify and interconnect every object and event with a standard format, and makes it easier and flexible for the third party control and management by integrating multiple services issued from cloud computing. The purpose of our proposed AIoT scheme is to build a smart world of always on, always-awareness, always-connected, always-controllable, and establish an "intelligent networking" based relationship among the objects, service suppliers and the third party users. In the scope of AIoT, all the objects are transparent across the networks and can be identified and controlled (with security guarantees) via a standard prototype anytime and anywhere.