From 7.5th floor:

Data management in the worldwide sensor web draws the big picture in mentioning that now too much attention has been placed on the networking issues of distributed sensing and too little on tools to manage, analyze and understand the data. The authors ask the question weather we can design sensor networks with data quality in mind? They ask a very crucial question, but as often in location-aware computing, it is very unclear on who can claim what quality in location information is or in other words who can answer “how good is good enough?”. Of course it is important to manage temporal and spatial data and handle their inherent uncertainty (e.g. via probabilistic theory) or mask it (e.g. via interpolation) or play with it (seamful design). It seems clear now that my thesis is about acknowledging that situation (uncertainty in the location information, fluctuant quality in the data), but instead of aiming to produce “perfect data”, I plan to provide an understanding and solutions from a human and urban perspective. It comes, at the first place, with the observation of people experiencing location-aware systems in CatchBob!, and making use of location information, in my taxi driver (co-evolution, context and granularity). This observations help me accumulating evidences on the contextual factors influencing the granularity (≈human expectation of quality) of the location information used.

Balazinska, M., Deshpande, A., Franklin, M. J., Gibbons, P. B., Gray, J., Hansen, M., Liebhold, M., Nath, S., Szalay, A., and Tao, V. (2007). Data management in the worldwide sensor web. IEEE Pervasive Computing, 6(2):30–40.

A common scenario for WSN often feature masters or base stations in charge of coordinating the application functionality. Although this centralized approach is appropriate for some applications, there are other situations in which distributed control and processing is necessary to implement more complex control loops. The generalized Wireless Sensor and Actuator Network (WSAN) is the scope researchers are now exploring to come up with more decentralized architectures that encompass multiple sinks and heterogeneous nodes. In such settings, new programming abstractions are required to manage complexity and heterogeneity without sacrificing efficiency.

Logical Neighborhoods (LN) is a novel programming abstraction for WSNs. A logical neighborhood includes nodes whose dependable roles in the network are specified declaratively, along with requirements about the cost of the communication involved, and regardless of the physical neighbors related to the node’s radio range. This enable the programmer to slice the network according to the application needs, effectively replacing the physical neighborhood with a higher-level, application-defined notion of proximity.

Late last year, at the flagship conference on wireless sensor networks: ACM SenSys 07 held in Sydney, Australia, Luca Mottola and G.P. Picco received the Best Demo Award for the demo “Programming WSN with Logical Neighborhoods: A Road Tunnel Use Case”.
The original LN papers can be found here and here.

Further info is available on the dedicated Web site.

This is the tittle of an interesting paper on WSN to be presented in HotNets-VI, a 2 days ACM supported workshop to be held this week in Atlanta, Georgia, USA.

Please be aware this is strictly related to WSN. As far as we know, no research has yet supported extending the concept to humans!

The paper can be downloaded here

All you need is a couple of Tmote Sky boards, cygwin and Java you can start doing software-based energy profiling in Contiki. If you are at SenSys’07 in Sydney - watch out for the demo of `software based energy estimation’ by SICS Sweden on 7th Nov, otherwise get more information here.

Accenture Technology Labs is taking interest in sensornets. The emerging trend of Sensor Telemetry combines data—historical and current—with two-way wireless communications to offer unprecedented visibility into and management of equipment, products and interactions. It promises organizations more detailed, real-time views, not just of individual business transactions, but of physical state and operations, and human conditions. Sensor Telemetry will also enable organizations to respond faster and even predict incidents before they occur.

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Considering a wireless sensor network whose nodes are distributed randomly over a given area, a probability model for the network lifetime is provided. Using this model and assuming that packet generation follows a Poisson distribution, an analytical expression for the complementary cumulative density function (CCDF) of the lifetime is obtained. Using this CCDF, one can accurately find the probability that the network achieves a given lifetime. It is also shown that when the number of sensors, N, is large, with an error exponentially decaying with N, one can predict whether or not a certain lifetime can be achieved. The results of this work are obtained for both multi-hop and single-hop wireless sensor networks and are verified with computer simulation. The approaches of this paper are shown to be applicable to other packet generation models and the effect of the area shape is also investigated.

By M. Noori et al.

More info here.

Recently, researchers are feeling the need for “a” sensornet architecture. We blogged about the WSNA workshop with IPSN’07 sometime back, it was the first event to bring together people interested in sensornet architectures. Below is a list of some selected papers from the workshop, you are encouraged to look at the complete program:

• A Modular Sensornet Architecture: Past, Present, and Future Directions
• Toward a Unified Radio Power Management Architecture for Wireless Sensor Networks
• An Architecture for Energy Management in Wireless Sensor Networks
  

Third International Workshop on Algorithmic Aspects of Wireless Sensor Networks
July 14, 2006, Wroclaw, Poland
To be held in conjunction with ICALP 2007.
http://algosensors2007.im.pwr.wroc.pl

Call for papers is available here.

In spite of several years of intense research, the area of security and cryptography in Wireless Sensor Networks (WSNs) still has a number of open problems. On the other hand, the advent of Identity-Based Encryption (IBE) has enabled a wide range of new cryptographic solutions. In this work, we argue that IBE is ideal for WSNs and vice versa. We discuss the synergy between the systems, describe how WSNs can take advantage of IBE, and present results for computation of the Tate pairing over resource constrained nodes.

The paper by Leonardo B. Oliveira and Diego Aranha and Eduardo Morais and Felipe Daguano and Julio Lo’pez and Ricardo Dahab can be downloaded here.