Risks of AJAX

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Risks of AJAX

• CSC 867
• Advanced Topic Presentation
• By David Frank

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What is AJAX

• AJAX is a JavaScript object allowing to use
  XMLHttpRequest object easier and speeding up
  development of AJAX based projects.
• It consists of a bound of methods which help to
  create queries, error handling, usage with HTML
  forms as well as connection timeouts and
  reconnecting.
• The Best feature of AJAX is that it makes changes
  to the page without having to refresh it.

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Risks of AJAX
Marketing Risk
Cultural Risk
Technology Risk
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Technology Risk

• Reach Risk
• All Browsers are different. Compatibility with
  ALL the available browsers is impossible. A
  feature considered to be very good in one browser
  will not even work in another. Every feature is
  thus designed to reach only the target browser.
  So, not all browsers can get the advantages of
  AJAX.

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Technology Risk

• Maintenance Risk
• Ajax code is difficult to maintain because it is
  complex. A lot of optimization techniques in the
  script are needed to improve performance. These
  lead to spaghetti code resulting in higher long
  term maintenance costs than the applications that
  are written in a traditional architecture that
  rely more on server side processing.

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Technology Risk

• Forwards Compatibility Risk
• Ajax applications have to continuously be
  rewritten as new browsers and operating systems
  are introduced in the technology industry. This
  is to accommodate changes in the layout engine,
  CSS interpreter, and the underlying mechanisms of
  JavaScript itself. Developers need to be one step
  ahead of all possible changes that would affect
  the user experience.

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Cultural Risk

• Heterogenous culture and expectations
• Ajax has a way of making things happen really
  quickly on a page and so without enough visual
  cues there will be bad usability. If an item on
  the web page is usually clicked rather than
  dragged (because of AJAX), then the user will not
  be comfortable with the interface, though the
  drag object might be easier to use. The problem
  of the Back button in web pages due to AJAX is
  one of the frequent usability issues encountered,
  since the Back button cannot undo the changes
  made by AJAX.

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Cultural Risk

• Users are not very trainable
• Not all users are fast learners. Most of the
  users will not feel comfortable with such an
  advanced technology. The users learn gradually
  and by the time they get acclimatized to the
  interface, the technology has changed, thus
  leading to a newer and higher technology
  interface.

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Cultural Risk

• Short attention span
• AJAX takes a lot of time to load. Making AJAX
  scripting to be supported in many browsers leads
  to huge file sizes for client side Ajax code.
  With almost half of the web users having dial-up
  internet connection, the risk here is that with
  short attention spans, users can become
  frustrated or bored by high latency or download
  times and abandon the session.

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Ways to reduce Risks

• Technology Risks
• Usage of 3rd party framework
• There are several well optimized third party
  AJAX frameworks that are available. These have
  already solved many of the cross browser issues.
  There are also constantly upgraded to support the
  latest updates of the browsers. By using these
  third party frameworks, a lot of time and money
  can be saved.

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Ways to reduce Risks

• Technology Risks
• More processing on the server
• The size and complexity of a client side code
  can be reduced by moving as much processing as
  possible to the server. If the client has less
  code, it is easier to maintain and debug. A very
  good example of this is calling the server for
  raw HTML code instead of data, thereby
  eliminating the need to perform JavaScript
  transformations on the client.

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Ways to reduce Risks

• Technology Risks
• Perform regular testing
• AJAX applications need to be tested continuously
  to ensure that long term success is achieved with
  the various browsers. The target browsers must
  also be reviewed from time to time so that the
  latest versions of the browsers, including the
  BETA versions, are taken into consideration while
  designing the pages.

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Ways to reduce Risks

• Cultural Risks
• Affordance testing
• Affordance testing can be done in order to
  understand how users interact to web pages.
  Before using a functionality, another application
  with a similar functionality can be tried so that
  known pitfalls of AJAX can be avoided.

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Ways to reduce Risks

• Cultural Risks
• Keep it lightweight
• The amount of AJAX code should be reduced to as
  minimum as possible. The AJAX codes can be
  written by keeping the download speeds of a 56K
  modem. The page can be designed in such a way as
  to download within 15 seconds while using a
  dial-up connection.

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Ways to reduce Risks

• Cultural Risks
• AJAX used only to increase functionality
• AJAX should be used only where its necessary.
  For example, when trying to decide between a
  clickable and a draggable object, a draggable
  object can be used when there is a necessity to
  reorder items in a list. Otherwise, the
  clickable object can be used. This will enhance
  user functionality and reduce any required user
  training.

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Ways to reduce Risks

• Cultural Risks
• Liberal use of visual cues
• Visual cues help in making interacting
  accessible to a more diverse audience. The user
  should be given enough visual cues to indicate
  that AJAX is working. These visual cues assist in
  the rapid training of users. One very good
  example of a visual cue is the red loading box
  in Gmail. Gmail gives a red box with the words
  loading inside it, when the browser has done
  loading the page and AJAX is now working on the
  page.

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Conclusion

• Though there are several open standards like CSS
  and HTML, the websites are being made to support
  advanced AJAXian techniques. Developers who want
  to improve their interfaces can use AJAX but will
  have to follow the examples of good interfaces
  such as Gmail. Gmail is an example of terrific
  innovation - but at the same time has designed
  the interface after understanding its users. Thus
  the best interface that uses AJAX comes only
  after taking considerably the various
  technological and cultural risks in todays
  world.