New world, old rules

In the new world of Internet-based e-business, we use business methods and processes that, up to recently, did not exist.

But we still need to connect these Web front-ends to the existing back-end systems (likely traditional processing environments) in order to use existing business functions and to access and maintain data in these corporate repositories.

IT professionals know that the old rules of interfacing systems remain important. Connecting the front end systems to the back end, whether for e-business or any other purpose, requires an up-front understanding of how these systems operate and the use of process rules for maintaining data interaction.

There are several critical factors for a successful deployment. These include data synchronization and integrity; data source integrity; multiple data source and process synchronization timing; performance; and testing. These factors, while always important, are now even more so, given the number of interfaces that can be used within one Web based e-business portal and its related functions. Let’s examine them further.

“Garbage-In/Garbage-Out” has always been a mantra of the IT industry. Before you create or connect an interface to another system, you must verify the integrity and accuracy of that data source. Ask yourself if the data needs to be cleansed before you can use it. In any situation where the data is duplicated, each system operates under the premise that its version of the data is accurate. Verification of the data synchronization and integrity is required to keep duplicate data consistent with the original source, including context-related data.

To review process synchronization, you must examine how the relationship will work. Ask the following questions: When are updates actually applied by the back-end system? Will a delayed or batch-style update model in the back-end system compromise the integrity of the front-end system? How are the relationships to critical back-end information maintained during the period of the outstanding updates (e.g., stock being purchased, but not immediately being removed from inventory)? Are the back-end data sources only copies of the real data (for performance and/or access reasons) and what is the refresh process and timing? Answering these questions may eliminate some nasty surprises. Process synchronization may require additional processing on the front-end.

This may describe the simple case of one back-end data source, but what about more complex interfaces to multiple back-end systems as part of one function? Now it is necessary to consider not only how the front-end functions will co-ordinate the data, but also how these back-end systems co-ordinate data among themselves.

Add to this mix the superset of these transactions, the manner of handling (file transfers or transactions) and the timing of the transactions (batch, immediate or delayed store and forward) between the front-end services and each of the back-end systems. Data inconsistencies will arise when data from one back-end system is used to update data in another system before the two back-end systems have done any data co-ordination of their own. Expect strange and erratic results if you process your data this way.

But if we’ve maintained data consistency, but what about performance? Too many times we have watched a Web application slow to a crawl or fail completely because it is loaded beyond the capability of the infrastructure. Site performance is more than just Web server performance. It includes the ability of the back-end systems to support the additional load of the e-business front-end.

Perform usability and ergonomic testing. Invite trusted customers to be testers – they will have suggestions for ergonomic and process improvements that could also affect performance. Use many scenarios and repeat them with variations.

Do not skip stress testing. Load the system and include the back-end systems as part of the test. Ideally, the integration, system and stress test environments are a complete copy of the production environment. Remember that customers are turned off – sometimes irretrievably – by poor or erratic performance.

There are many different ways of implementing rules that acknowledge these critical success factors, but the principles remain the same for protecting the integrity and accuracy of any business process. If done correctly, the connection of front-end and back-end systems will help ensure that the Internet-based processes will work right, every time. Even in the new world of e- commerce, “old world” rules continue to add value.

Ernst ( is director of technology in the consulting practice at EDS Systemhouse Inc. He is responsible for technology and architecture within the practice.