Low-bandwidth business apps gain vision
Choosing the best application server solution for your site demands that you closely examine your business and technical requirements, as well as the capabilities supported by the solution at hand. Given the sheer number of application-server solutions available today, the task can easily become quite challenging.
Organizations that need an application server capable of supporting distributed deployments to low-bandwidth clients should consider an evaluation of Emrys Solutions Inc.’s Visions 1.0. Visions offers useful caching technology that speeds up application interaction, especially across slower connections. The caching technology, together with support for Windows, Web and wireless clients, makes Visions ideal for sites with mixed connectivity and client-side requirements.
However, this first version of Emrys Visions is still rather rocky, limiting, and immature when compared to rival application-server offerings. Among other things, the Emrys application server is limited to Windows platforms, whereas rivals, such as BEA and IBM, support a wider number of platforms. Emrys officials have indicated that the company plans to add support for Solaris and Linux in the near future.
Likewise, Emrys Visions’ load-balancing capabilities are not as customizable as are some other solutions. Moreover, outside of ODBC access to enterprise data, Visions doesn’t offer built-in support for integrating other enterprise resources – such as transaction systems – in the same way that rival InfoSpinner’s ForeSite does. However, Emrys Visions is more affordable than some solutions.
Five modules compose Emrys Visions: Visions Editor, Application Manager, Resource Manager, Information Manager, and Thin Client View Managers. The Visions Editor is a development environment that is reminiscent of Microsoft’s Visual Studio. Developers who have used that Microsoft product will find a similar metaphor in the Visions Editor.
As its name implies, the Application Manager controls the execution of your server-side application components. The Resource Manager supports the load-balancing function together with monitoring and management tools.
The Information Manager provides ODBC access to relational data. Emrys Visions includes optimized support for Pervasive SQL databases.
There are two types of Thin Client View Managers: Standard and Custom. The Standard View Manager supports Windows clients, which can be updated from the server. It has a small footprint and can be set up not to use shared Dynamic Link Libraries – save when support is needed for charts and graphs. Custom View Managers can support Windows, Web and wireless clients.
I found the Emrys Visions installation process automated and easy enough to complete. However, I encountered some problems with both the application-server and development-tool components of Visions. In the case of the application server, it seemed to hang regularly during configuration tasks and at times when I was trying to monitor server processes.
During development of my test applications, the Visions Editor regularly entered a circular error-message pattern. The error messages, which popped up continuously at times, were strange and did not seem to relate to my application logic at all. I was eventually able to build and deploy some simple applications, though the going was rough.
Once deployed, my test clients – which were mixed – were able to access the test applications and data without incident. Emrys Visions had stored my test screens and reports as separate resource files, which were cached during run time. This seemed to speed things up – even across a test 28.8Kbps dial-up connection.
Emrys does provide good security via multiple measures that can be enforced at a connectivity, data-access or user-access level. For example, Visions offers Secure Sockets Layer support as well as a field-level application security setting.
The amount of documentation available was scant when compared to other products, but typical of a first-release product. The only documentation I found was a Windows-based help file for the Visions Editor and a PDF document regarding the Emrys Enterprise Commerce Applications (a suite of electronic-commerce applications that the company has built using Visions).
The company will need to bolster the on-line documents to include detailed information on all Emrys Visions components. Some step-by-step tutorial materials should also be added to assist those new to application server technologies. There were no hard-copy documents available during my review.
Emrys Visions may not yet contain all the mature trappings of some of its application-server rivals, and the company does need to address the first-release issues I noted above. However, Emrys is the first application server I’ve tested that does a good job of focusing on client-side performance in low-and high-bandwidth settings. Given some refinement and added capabilities, over time Emrys Visions could be a strong contender in the application-server market.
