![](bg5.png)
4 DISCUSSION
The procedure of discovering environmental services
can be automated by selecting some sensor device
from the list returned by the .env DNS server, pars-
ing its WADL file and constructing HTTP requests.
This process can even be personalized, by select-
ing only devices that meet particular user preferences.
For example, some users may wish to interact solely
with devices having positive online feedback or those
belonging to well-known authorities such as govern-
mental organizations. User characteristics could be
extracted from their online social networking status.
Since the whole idea is participatory-based, only
people who are willing to share their sensor devices
with the online community would do so. We believe
that in the future a culture could be created around
the concept of sharing environmental services with
the rest of the world.
Even though our proposal targets environmental
services, it could be well generalized to support any
kind of physical devices and/or pervasive services.
To achieve this, standardized ”domain vocabularies”
need to be created, for facilitating the construction of
queries by end users. For example, a user that wishes
to park his car in Barcelona could just need to type in
his Web browser parking.cars.Barcelona.
Finally, defining extended environmental ontolo-
gies would encourage automatic information re-
trieval, generalized inferences and advanced Web
mashup development very easily. For example, when
the temperature in Porto is obtained, then the general
temperature of Portugal can be automatically inferred.
5 CONCLUSIONS
Embedded computing is becoming ubiquitous in our
everyday lives, being slowly-slowly blended with the
Web. Discovering in real-time miniaturized Web-
enabled sensor devices, deployed around the world,
is a problem that needs to be effectively solved.
In this paper, we investigated theoretically how the
DNS could be extended to support global discovery of
environmental services. Our small research indicates
that it may be feasible to achieve automatic, real-time
discovery of sensor devices, by means of specialized
domain name servers. Definitely, our proposal con-
stitutes only a novel idea and it would require a great
willingness from Web engineers to be realized.
It would be interesting to study ways for extending
DNS-based discovery of any Web resource offering a
RESTful Web API. Security is another crucial factor
not discussed that requires extensive research.
For future work, we plan to experiment with
BIND
11
, which is an open-source DNS software for
Linux, implementing a .env DNS server in a local
environment, demonstrating the potential of this ap-
proach. In parallel, we will develop a Mozilla Firefox
extension that automatically discovers sensor devices
just by typing relevant URLs, constructs their host-
names and interacts with them.
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