* Inside Asynchronous JavaScript And XML
Companies deploy Web-based enterprise applications because they’re easy to support and deliver to a broad range of devices. In the 1990s, browsers became the platform for critical applications such as CRM and ERP. But Web applications also have serious drawbacks.
The traditional click-and-refresh model, in which each interaction causes another page to load, makes Web applications cumbersome, slow and by necessity feature-poor. Applications such as Outlook Web Access have tried to overcome the limitation of this model with copious use of proprietary technologies such as ActiveX. As a result, many of these applications can be used only with Internet Explorer, and expose companies to potential security risks.
Asynchronous JavaScript And XML (AJAX) can potentially address these issues.
In the AJAX Web-application development model, the browser runs fairly complex JavaScript for the user interface, while asynchronously accessing XML data from a server. This effectively moves the presentation layer from the server to the client, resulting in much snappier and richer applications. Examples of AJAX-developed technology can be seen in a number of consumer Web services, such as Google Maps, Google Suggest, Google Groups and Flickr.
What’s more interesting for enterprise customers is the rapid adoption of the AJAX model in development environments. Nemertes Research predicts that AJAX-like interfaces will soon appear in many critical enterprise applications – improving application performance without requiring massive upgrades in data-center bandwidth and network infrastructure.
This week, Microsoft announced it is building AJAX interface development into its Visual Studio development environment. Google has released an API for XSL stylesheet implementation over AJAX. In the open-source arena, an exciting framework for AJAX development is Ruby on Rails, which has a small but fiercely enthusiastic following. Others will surely follow.
Skeptics should test-drive some of the aforementioned apps – as a longtime code developer and user, the first time I used Google Maps I was astonished at how different this type of interface felt. More importantly though, there are some clear advantages beyond the interface:
* Since the presentation is handled by the browser, less information has to be transmitted – leading to significant reductions in bandwidth. For companies with branch offices, AJAX applications can generate savings on costly last-mile WAN connections.
* AJAX can leverage your investments in XML data storage. Companies can use AJAX as a stepping stone on a Web services/SOA roadmap.
* Enterprises can leverage AJAX to expand their adoption of Web-based applications, without adversely affecting performance (particularly key for remote and distributed users).
Several challenges still lie ahead for AJAX. While it has broad support among the various browser platforms, its implementation is often flawed from a security perspective. Also, without some development framework, AJAX applications can become a spaghetti tangle of unmaintainable code. Nevertheless, once you have experienced an AJAX interface you may wonder how you could ever again use a Web-based application without it. Making Web applications more functional and less bandwidth- and latency-constrained will strengthen the trend of data center consolidation and zero-footprint branches.
