Researchers:

Mário Alves
Eduardo Tovar
Anis Koubâa
Shashi Prabh
Stefano Tennina
Nuno Pereira
Ricardo Severino
Claro Noda
Hossein Fotouhi
Manuel Santos
Athanasios Garyfalos
Nouha Baccour (external collaborator, ReDCAD Research Unit, ENIS, Tunisia)

Synopsys

Wireless Sensor Networks (WSNs) are triggering a new era in Information and Communication Technologies. These networks of tiny embedded computing systems are enabling a new set of large-scale monitoring and control applications such as for pervasive Internet, homeland security, critical physical infrastructures monitoring, precision agriculture, environmental monitoring or intelligent transportation systems.

CISTER has been assuming international leadership in the WSNs scientific area, namely on supporting Quality-of-Service (QoS), particularly focusing on timeliness and real-time, reliability and energy-efficiency aspects.

We are addressing the use of both standard and COTS technology and cutting-edge solutions designed from scratch. CISTER pursues excellence-level collaborative R&D sustained by analytical, simulation and experimental models. We have recently designed, implemented and deployed the largest WSN test-bed in Europe to date, with 300+ sensor nodes.

On Going Research

CISTER researchers are world leaders on IEEE 802.15.4 and ZigBee technologies (ART-WiSe). We have provided methodologies to analyze, dimension and engineer WSNs with improved QoS and the open-ZB toolset has been made publicly available (over 100000 visits and 6000 downloads - average 4-5 downloads per day). It includes: (i) the implementation of the IEEE 802.15.4 protocol in TinyOS, for the MICAz and TelosB motes; (ii) the implementation of the ZigBee Network Layer for supporting synchronized multiple cluster topologies (the Cluster-Tree topology) in TinyOS, for the TelosB motes; (iii) simulation models of the IEEE 802.15.4 and ZigBee protocols in OPNET; (iv) a MATLAB tool for timing analysis and network dimensioning, based on Network Calculus. This framework triggered the creation of the TinyOS 15.4 and ZigBee Working Groups, in which CISTER researchers have been actively involved.

In what respects WSN research within the CONET NoE, CISTER is leading the COTS4QoS and participating in the RMA research cluster. In COTS4QoS we are essentially interested on enabling/improving different QoS properties in WSNs using standard and COTS technologies as a baseline. RMA focuses on resource management and adaptation in WSNs and BSNs, addressing radio diversity, interference modelling and link quality estimation.

CISTER researchers have been doing cutting edge research on radio interference and link quality estimation, which is a basic building block for supporting higher level protocols and mechanims such as routing, mobility management, fault-tolerance, deployment and topology control. We have proposed an innovative link quality estimator (LQE) based on Fuzzy Logic (F-LQE) that shows significant benefits over existing ones and the RadiaLE benchmarking toolset for the performance evaluation of LQEs, available as an open-source. Within this framework, the EWSN/CONET MSc Thesis Award 2011 was co-supervised by a CISTER researcher.

CISTER researchers have also been fostering research work on Hexagonal WSNs, in which nodes are logically connected to six peer neighbor nodes. This network model enables simple and low-overhead protocols, which are very atractive from the point of view of resource constrained WSNs and bounded end-to-end communication delays (for fulfilling real-time requirements).

Another paradigmatic example on how CISTER aims at pushing the state-of-the-art in WSNs is on building a real-world deployment with 10000 nodes (one order of magnitude higher that the largest WSN deployed so far), within the context and timeframe (3 years) of the EMMON project, lead by Portuguese hi-tech company Critical Software. Within this project we have been designing a scalable and hierarchical WSN architecture coping with QoS properties such as timeliness and scalability. The EMMON consortium recently presented a live demonstration of an integrated system prototype at ISEP, a monitoring application encompassing all system components, ranging from hardware, communication architecture, middleware and command and control GUI. This was instantiated in a WSN deployment of over 300 sensor nodes - TOBK the largest WSN test-bed in Europe so far.

In what concerns application-driven R&D, we highlight the work on using WSNs for structural health monitoring (under a collaboration with ISISE), for energy-efficient data centres (under the SENODS project) and for energy-efficient buildings (under the EMMON and more recently under the ENCOURAGE projects).

Projects & Leadership

International Projects

We are one of the leading partners in the EMMON project, within the Artemis programme. CISTER leads WP4 “Research on Protocols & Communication Systems” and several tasks related to the specification of the WSN architecture and the design of time and energy-efficient data aggregation and resource allocation mechanisms.

CISTER is a core partner in the European Network of Excellence on Cooperating Objects (CONET). Under CONET and more related to the WSN area, we are leading the COTS4QoS (QoS provision using COTS) and participating in the RMA (resource management and adaptation) research cluster.

More recently, we started researching on the use of WSNs for energy-efficient data centres and buildings, under the SENODS (PT-CMU) ENCOURAGE (ARTEMIS) projects, respectively.

The members of the CISTER WSN team have been publishing tens of highly cited papers in top-notch journals (e.g. ACM Transactions on Sensor Networks, Elsevier Ad-Hoc Networks Journal, Real‐Time Systems Journal, IEEE Transactions on Industrial Informatics) and conferences (e.g. EWSN, IEEE MASS, ACM/IEEE IPSN, IEEE RTSS, ECRTS, IEEE RTCSA). Some of our papers have over 10 citations per year.

A list of publication targets which we consider relevant within our research areas is available here.