Rules for Sustainable Application Integration
By Hemen Goswami
Mumbai, Jun 20, 2008

Organizations across various domains are facing challenges to integrate their enterprise application suites. Acquisitions and mergers have created additional need to integrate most diverse applications and processes. The trend is increasing, and the challenge is to create an innovative integration solution that meets customized needs of a specific organization.

Key objectives of enterprise integration:

* Maximize returns of IT investments

Integration enhances collaboration between enterprise applications, which enables leverage each other's capability. It is important to create synergy between IT governance and the execution mechanism of enterprise integration road map.

* Align business processes

This is another critical need. In fact, it is a corollary of the first objective. Execution of business processes is all about collaboration to avoid redundancy and inefficiency. It is to create a perfect synergy.

* Create interoperability between heterogeneous applications

Organization owns multiple heterogeneous applications. Integration framework provides the way to set up an inter-operable application landscape.

Desired Features of an Integration Policy

There are multiple features that an integration policy must exhibit. The key features that I feel are fundamental towards a successful integration policy are:

*Create a uniform, long-term, and sustainable enterprise integration policy

The integration policy must be uniform, long-term, and sustainable. Policy makers have to visualize a near-term as well as a long-term enterprise landscape. The policy should be broad based to support continuous growth over a long period. The policy should envision future IT enterprise investments, and the general framework must be able to encompass the future investments; it should support the mechanism for future enhancements and standards in the existing infrastructure. It should also allow future needs of the business users to be added easily. Similarly the policy must allow retiring the deprecated parts of the infrastructure as new requirements evolve.

* Define a cost effective integration architecture framework

The big challenge is to create a cost effective solution. The IT policy has to dictate an integration architecture framework, which gives cost optimality. The goal is to create a scalable and open architecture framework to allow easy integration with minimal development cost. The usage of open standards, best practices of Service Oriented Architecture (SOA) and rule-based configurations shall play significant role in the integration architecture. The integration architecture should be founded on easier development methodologies. It should be possible to use the best of the development IDE and user interface tools to aid in the development. The compilers and validation tools for any custom syntax need to be provided to reduce the development time. Integration architects must leverage pattern-based development to allow easy integration.

* Create a less-intrusive architecture framework

The main issue is how to expose internals of existing legacy applications that do not generally conform to integration standards, and at the same time ensuring that exposure is minimal. I consider this as the trickiest issue. Many legacy applications may not conform to the overall integration architecture layout. Now the question is: how much intrusion is allowed for such applications? A collaboration between the domain experienced people and the integration team shall play the vital role to assess the integration needs of the legacy applications. The policy should provide general hooks into the integration infrastructure through which the legacy applications could be communicated with. These hooks shall plug in bridge based custom components that are inclined toward integrating points of interaction with the legacy applications.

* Define a platform agnostic mediation framework

The integration requirements evolve and keep on changing. Rather than going for the direct integration of the applications, the integration framework must function as the mediator. The applications should have direct communication with the integration framework. The application entities need not be aware of the location and the presence of their peer. The framework as such provides services to mediate the request/response from the applications. The generic interfaces to accept requests/response from the third party applications should be defined. The framework should translate the application specific native requests to the platform agnostic formats and vice versa. In a more generic approach, the framework should act as a fa ade where it exchanges the dialogs with the application through fa ade interfaces rather than exchanging the dialogs in the application provided interfaces.

* Define automated testing guidelines

The policy should support an automated testing framework to minimize manual intervention and faster defect identification. The automated test framework strategy is essential to support the evolutionary development and implementation models. The policy can easily leverage the Test Driven Development (TDD) methodology. For example, the extreme programming (XP) can be leveraged, where test cases are developed first before a single line of integration code is implemented. The TDD shall assist in finding the possible integration problems at an early stage. I recommend usage of XP-style methodology for integration implementation, primarily due to the incremental implementation model practiced in an integration project.

* Define architecture framework's capabilities for high availability and load balancing

Business applications shall be able to provide consistent services if the underlying integration mechanism is reliable enough to eliminate the single point of failures from the integration framework. Fault-tolerance and redundancy management with proper load balancing are desired in any integration architecture framework.

To summarize, first and foremost, all organizations must create a collaborative governance and integration policy, which includes primary stakeholders of business processes. The plan must include the road map for projected business growth, and enterprise application investment. Plan the integration architecture backbone. The backbone must support vertical and horizontal growth patterns. Formalize the processes to define the life cycle of integration framework development. At development and implementation levels, provide general guidelines and checklists. Assess the existing and emerging tools, technologies and standards to be included in the integration framework.