are associated with sensors to create "widgets" that are added
to the user's dashboard for rapid visualization of sensor data.
When a dashboard is displayed in the browser, it requests the
user's dashboard configuration and dynamically draws the
various visuals containing sensor data.
A key difference between WoTKit and other web centrictoolkits
is in how visualization and processing facilities are
delivered. Rather than providing these components as
applications or plug-ins, they are provided as core system
facilities. Like others, the WoTKit serves as a sensor data
aggregator, visualization, remote control and processing tool.
It aggregates data from a variety of sensors, and allows simple
control messages to be passed to actuators. WoTKit allows
users to quickly fmd and subscribe to sensor data of interest,
process data and visualize the data using widgets on a
dashboard. By providing these built in facilities, we do not
prevent developers from creating their own applications; but
we supply easy to use baseline functionality for users to get up
and running quickly.
A. Sensor Gallery
The WoTKit sensor gallery provides a way for users to
search for sensors of interest that they have contributed
themselves, or that others have made available on the system.
Developers can elect to subscribe to a sensor, adding it to their
sensor list making it available for generating visualizations and
processing pipes.
B. Gateways and Thing Integration
Integration gateways for the WoTKit are generally simple
scripts that (optionally) register discovered sensors, gather data
from the sensors they serve, and push data into the system
either periodically or when the data changes. Because these
gateways are web clients, not servers themselves, they can be
located behind frrewalls. They typically consist of only a few
lines of code to register themselves, update their state, and get
control messages.
To illustrate, the following shell script posts the current
CPU use of a PC to a sensor to the default data fields called
value. This script assumes the CPU sensor has already been
registered on the system.