Sensor Networks’ Integration - Application and Multidisciplinary Aspects of Wireless Sensor Networks - page 105

on services only the collection of sensor samples becomes independent of specific
sensor network implementations as long as these networks are able to describe how
the service they provide can be used. Thirdly, the authors recognize the problem for
an autonomous device to manage multiple dynamic security associations and the
associated authorization decisions and therefore they propose to outsource the autho-
rization task to the CommonSense provider - something which is enabled by the
tiered SOA.
The proposed architecture is mapped on three technology planes: Communication
services, Application enablers, and Application plane (see Fig. 5.1 ). Applications
are built using common service blocks residing in the Application enablers' plane and
all are connected by a number of network solutions residing in the Communication
services plane.
Different domains are identified on each plane. The WSN, CommonSense, and
third-party service domains comprise the service plane, while the Peripheral,
Access, and Core domains comprise the Communication Services plane. The appli-
cation providers providing end-user applications reside on the application plane. In
the Applications plane the authors differentiate between existing applications that
do not depend on physical world context (e.g., call setup) and applications that can-
not exist without one (e.g., burglar alarm).
The Application enablers' plane is divided into three domains: WSN domain,
CommonSense domain, and third-party services domain. The WSN domain com-
prises all atomic sensor services, i.e., services provided by individual sensors or
sensor networks and used as small building blocks of more complex services
offered by the entities residing in the CommonSense domain. The CommonSense
domain is where the core functionality of the proposed architecture resides. This
domain does not host any specific applications, but provides a set of enablers for all
types of applications. These enablers include information exchange, sensor network
discovery, data processing, aggregation of atomic sensor network services (sensor
mash-ups), Authentication, Authorization, and Accounting (AAA) services. In short,
the domain creates the possibility of having a dynamic binding between applica-
tions and WSNs. It is mainly based on semantic technologies which provide access
independency. A single attachment point for sensor networks also facilitates security

Application Plane

Application Enabler
Plane

CommonSense

Communication Services
Plane

Access

Fig. 5.1 The proposed layering in CommonSense architecture