Adapting Medical Content to the Terminal Capabilities of Wireless Devices - E-Healthcare Systems and Wireless Communications - page 300

The fact that the User Agent header is present
to any HTTP request, along with its potentiality
to characterize the client platform, are exploited
by the WURFL community to provide an alter-
native but interoperable solution to UAProf and
MPEG-21 for adaptation of any web application
to terminal capabilities.
The WURFL project (WURFL home page),
created by Luca Passani and Andrea Trassati
near 2001, is the acronym for Wireless Univer-
sal Resource File . Member of the Open Source
community, WURFL attempts to solve the issue
of adaptation and presentation of content to wire-
less devices. Apart from valuable information
related to the project, the web site HTTP://wurfl.
sourceforge.net/ provides to anyone interested the
WURFL file that is a XML file including almost
all wireless devices with their corresponding
capabilities.
Within the WURFL file, the devices are distin-
guished by the description of the HTTP header user
agent provided by the browser of the correspond-
ing terminal device. For each nested device the
XML organization of the device's data is preferred
for the manageability and flexibility it provides,
as well as due to the fact that XML is recognized
by a variety of programs and applications.
In specific, the WURFL file is structured by
the root tag <devices >, within which the descrip-
tion of any nested device starts with the <device>
tag. This tag provides the following information:

<devices>
<<device user_agent=”O2-X1i” actual_
device_root=”true” fall_back=”opwv_
v61_generic” id=”o2_x1i_ver1”>

Then, inside the <device> , the capabilities
of a device are associated to groups of attributes,
so there is consistency in reading the file. These
groups are (inside the brackets the actual names
of the groups in the WURFL file):

1. Product info (product_info)
2. WML user interface (wml_ui)
3. Compact HTML user interface (chtml_ui)
4. HTML/XHTML-MP user interface
(xhtml_ui)
5. CSS support (css)
6. AJAX support (ajax)
7. Markup language support (markup)
8. Packages cache (cache)
9. Display properties (display)
10. Image format (image_format)
11. Any know bug (bugs)
12. Wireless Telephony Application support
(wta)
13. Security (security)
14. Wireless capabilities (bearer)
15. String restrictions (storage)
16. Object types support (object_download)
17. Video functions support (playback)
18. Digital rights management (drm)
19. Video streaming support (streaming)
20. WAP functions (wap_push)
21. MMS service (mms)
22. SMS service (sms)
23. Java support (j2me)
24. Sound capabilities (sound_format)
25. Flash capabilities (flash_lite)
26. Information transcoding (transcoding)
27. RSS support (rss_support)
28. PDF support (pdf_support)
29. Soon to remove capabilities (Deprecated)

• Id - unique attribute of the device.

• User Agent - text of the User Agent field of

the HTTP header.

• Actual device root - optional, distinguish

the record among the “cloned ones”, those
who are used to describe future models or
a series with similar capabilities.

• Fallback - extra information for the user

agent.

An example format of the <device> tag is as
follows: