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Among the governmental agencies, there exist many land-related
information systems well operated at the present moment. These
systems reveal common characteristics. That is they are
developed solely according to the requirements of the agencies
developing them. Each system is designed and tuned to fully
meet the particular needs of the specific agency. When it comes
to users from other agencies that have to access the systems,
many problems arise. For instance, when the cross-agencies data
are needed, users have to manually collect data of different
formats from systems in different agencies. This is
inconvenient as well as inefficient. If we could manage to
connect systems in related agencies, and have the compatibility
problems solved, we would be able to access data across systems
on-line directly through a single system. There are many
feasible approaches to cope with the integration of multiple
systems. In this thesis, we'll refer to one of the concepts of
multiple databases (or multi-databases), the federated
architecture, and discuss the feasibility of its application to
the land-related information systems. The issues of integrating
multiple systems are of wide range. However, we'll give a
general description to the characteristics of the federated
system, and put our efforts on selecting a data transformation
format to meet the system's integration requirements. Finally,
we'll follow the concept of the federated architecture to
implement a simplified system that has the network
communication established and provides on-line access to data
from different systems. We shall focus on the implementation of
the prototype of the architecture mentioned above with short
discussions on how data can be integrated.
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