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http://www.oracle.com/technology/oramag/oracle/06-may/o36field.html
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Applications for
Real-Time Access Oracle technologies
and tools simplify mobile and wireless application development. Database applications
for wireless handhelds have an important role for business IT because they
can increase productivity and lower costs for an enterprise. Let's look at an
experience I had designing and deploying a wireless application where access
was the key. My client, a large
healthcare network, wanted a better system. Physicians needed access to
patient records after hours. These physicians were at multiple geographically
dispersed locations, on call for consultation after the central office was
closed. The goal was to let them view necessary records for patients who
called, as well as to access a medication interaction database. The
physicians would also need to update patient records or add notes based on
their conversations. The application had to run on both wireless Palm-based
and Pocket PC-based handhelds. The challenge: Our team needed to develop a
prototype rapidly that would go out to a handful of testers, followed by a
rollout to about 150 users in the next phase. Designing Wireless Applications How did we go about
solving this problem? The first step was to decide what functionality was
needed: a "mobile" or "wireless" application. Mobility
implies offline access to data. Typically, the user has a small subset of the
database that resides locally on the handheld. The user can access this
information using Oracle Database Lite 10g
and make changes that will become part of the database when the handheld
reconnects and resyncs. For the healthcare network,
an offline application was impractical, because the volume of data that the
physicians needed wouldn't fit on the handhelds. Wireless, however,
offers real-time connectivity to the back-end database. Little or no data
resides on the handheld, which acts as the interface to the database. Our
team chose wireless for the physician application because users—the
doctors—had to be sure that they had the latest information, and they
needed to update patient records in real time.
Then we had to decide
on the two main components of our physician wireless database application. First,
we needed a middleware server to connect to the company's database; second,
we needed the handheld component. We chose Oracle Application Server
Wireless, which provides a communications channel from the back-end database
to the handhelds. In addition, it allows you to format output for different
handheld platforms, such as BlackBerry, Palm, and
Pocket PC, in a process called device definition. Furthermore, Oracle
Application Server Wireless provides built-in security that includes
authentication, encryption, and auditing. Authentication supports the same
roles and privileges that you find on a desktop installation—you can
even use the same usernames and passwords. Standard encryption, such as SSL,
is available. Auditing can use standard Oracle audit trails whenever a user
logs in, including who, when, and what commands the user issued. Failed
attempts to connect can also be logged, for later analysis. Federal privacy
laws such as HIPAA make security a paramount concern for all medical
applications; our wireless tool for physicians, because it accessed patient
records, required the highest level of security. To achieve this level
of security on a wireless app, user access to Oracle Application Server
Wireless should be with a virtual private network (VPN), just as if the user
were accessing the system from a laptop or home office. Some handhelds, such
as the BlackBerry, have an enterprise VPN built in.
Others require a third-party mobile VPN. Our team used a VPN for the
physician application. The handheld component
of our physician app required no special client-side processing. The simplest
solution for such applications uses the handheld's native Web browser to
access a Web-based application. This eliminates the need for creating and
maintaining different interfaces on different platforms. However, it does
require that the back end perform all needed processing: The handheld is just
an interface. Wireless Development Success With the right tools,
technology, and techniques, developing database applications for mobile or
offline and wireless handhelds is not much different from ordinary
development. Using this solution, our clients benefited from real-time access
to the data they needed, from practically anywhere. Your users can, too. |
