Implementing the Software Platform Solution to Application Infrastructure

The previous sections outlined activities that you could use not only to develop a holistic perspective of the current technologies that have been employed to develop applications in your organization, but also to look over the horizon to what types of technologies, applications, and integration mechanisms could be in line for the future. This information is core to establishing an application infrastructure solution because it allows you to identify

• The common stack of application infrastructure solutions (such as application servers, database servers, and directory servers) that a high percentage of your current and, most importantly, the future application portfolio can leverage.

• The stovepipe technologies and applications that will render themselves to be labeled inconsistent and hence legacy over time but can be integrated with other applications via application infrastructure solutions to form composite applications .

• The emerging technologies that must be embraced to evolve the current application portfolio.

Taking into consideration everything that has been discussed so far in this chapter, the best approach to implementing any application infrastructure solution is to take the software platform approach, where your business applications and their supporting technologies are seen to be part of a related , interlocking software architecture rather than marriages between independent initiatives.

As illustrated in Figure 8.5, a software platform approach involves the following layers :

Figure 8.5. The software platform approach to resolving an application infrastructure solution.

• Platform ” Groups interoperable application infrastructure solutions into their technical domains ”for example, application server, databases, and integration servers.

• Services ” Shifts the responsibility of certain nonfunctional services from the application domain and into the application infrastructure domain, so it can be shared by multiple applications. The objective of services is to minimize the coupling between the infrastructure and application domains.

• Patterns ” Enables business requirements to be mapped to existing infrastructure designs that provide an end-to-end component or service-based solution for a specific class of application. The infrastructure designs are based on the application infrastructure solutions that have been selected to form the platform.

Note

Infrastructure patterns also include a physical infrastructure solution, as illustrated in Figure 8.3. A software platform approach in most cases is hardware, operating system, and network independent.

The software platform approach implies only those application infrastructure solutions that meet the current and future business requirements will be part of the Platform layer. All others will be considered part of an integration initiative. Even though your application infrastructure foundation may be reduced to solutions from a few vendors , perhaps one for each technical domain, there are advantages to taking this approach:

• The development and management of business solutions are simplified because the number of technologies that an organization must support is greatly reduced.

• The life of existing technology investments is extended because an organization can integrate legacy technology with a modern foundation that developers can use to create composite applications.

• The time-to-market of business solutions is accelerated by leveraging skill sets within a focused and proven technology selection.

By adopting a software platform approach, organizations can develop enterprise business applications through a common set of infrastructure services that are connected, aggregated, and presented by a common presentation framework. Each technical domain of the platform must be based on the open standards that exist for that domain, which not only preserves an organization's investment in that technology, but also enables the technical domains to be interoperable so that composite applications can leverage all the functionality provided by the platform. Also, because the software platform serves as the foundation for multiple mission-critical as well as non “mission-critical operations, all the application infrastructure solutions that constitute the software platform must collectively provide the following Quality of Service (QoS) attributes:

• Reliability ” Ensures that applications never "break," even under the most demanding circumstances.

• Availability ” Enables applications that can operate continuously 24x7x365.

• Scalability ” Allows companies to cost effectively embrace any level of application usage.

• Trusted security ” Enables an organization to maintain complete control of its intellectual properties.

Note

Scalability, high availability, security, application management, and Web services are examples of non-J2EE features.