<Field type=’string’>French</Field>
<Field type=’string’>cheap</Field>
</TupleData>
</InputTuple>
Thirdly, while this is a simple demonstration, it
demonstrates the potential practical applicability of
eLindaWS. In particular, it would be a cost-effective
solution to this problem in the South African context,
where cellphone usage is far more widespread than
general Internet usage, and mobile data rates are con-
siderably cheaper than voice or SMS rates.
5 CONCLUSIONS
Our previous research has demonstrated both the de-
sirable simplicity and the improved performance that
can be obtained by extending traditional Linda sys-
tems with programmable matching facilities. The re-
search presented in this paper demonstrates that these
advantages can be extended to the field of distributed
web service applications.
The facility-locating midlet application demon-
strates that eLindaWS is suitable for use in mobile,
location-based applications, and illustrates the use of
a parameterized programmable matcher. While it
is only intended as a proof-of-concept prototype, it
functions in a realistic way, and could potentially be
the basis for a useful and cost-effective commercial
application, particularly in our South African context.
Future work to improve eLindaWS is likely to
concentrate on optimization, in particular:
• The optimization of the creation and parsing of
the XML documents (Ranganath et al., 2006)
• Improving the communication protocol used to
send the XML documents, especially for LAN
configurations
• Preprocessing the tuples before storing them in a
tuple space, e.g. indexing of the tuples, sorting of
the tuples, or other methods
ACKNOWLEDGEMENTS
This work was supported by the Distributed Mul-
timedia Center of Excellence in the Department of
Computer Science at Rhodes University, funded by
Telkom, Business Connexion, Comverse, Verso Tech-
nologies, StorTech, Tellabs, Amatole Telecommu-
nication Services, Mars Technologies, Bright Ideas
Projects 39 and THRIP. Financial support was also
received from the National Research Foundation.
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