Information Technology Reference
In-Depth Information
ately with different browser versions. However, the browser checking is done
manually to assess the “look & feel” of the GUI, etc., similar to usability testing
discussed above.
Other specialized testing include accessibility for blind and disabled people,
runtime error detection, web security testing, etc.
[29,37]
.
4 . 2 M o d e l i n g a n d Te s t i n g W e b N a v i g a t i o n s a s F i n i t e - S t a t e
M a c h i n e s ( F S M s )
As mentioned in Section
3
, web navigations have many similarities with menu se-
lections in traditional menu-driven software systems, and the most commonly used
testing technique for such systems is based on finite-state machines (FSMs)
[5,48]
.
From the web users' point of view, each web-based application or function consists
of various components, stages, or steps, visible to the web users, and typically ini-
tiated by them, making FSM-based testing an appropriate choice. We next consider
the basic elements of FSMs and map them to web-based applications:
Each web page corresponds to a state in an FSM. When we start a web browser,
the default starting page or our customized starting page will be loaded, which
corresponds to the initial state. Therefore, potentially any page can be the initial
state. Similarly, we can stop anytime by exiting the web browser, or implicitly
by no longer requesting pages. This last page visited, which can be potentially
any page, is then the final state.
State transitions correspond to web navigations following hypertext links em-
bedded in HTML documents and other web contents.
The input and output associated with such navigations are fairly simple and
straightforward: The input is the clicking of the embedded link shown as high-
lighted content. The corresponding output is the loading of the requested page
or content with accompanying messages indicating the HTML status, error or
other messages, etc.
One special case in the state transition modeling above is that a user may choose
to follow a previous saved link (bookmarked favorites) or to directly type a URL
(universal resource locator, the address of a specific page). The use of these external
navigation tools makes state transitions more unpredictable. However, there are also
two factors worth noting in modeling web navigations as state transitions in FSMs:
From the point of view of Internet- and web-based service providers, it is more
important to ensure that the “official” embedded links on the providers' web
site are correct than to ensure that the users' bookmarks or typed URLs are
up-to-date or correct.
