We implement SOA for two major reasons. First is the ability to save development dollars through reuse of services. These services may have been built inside or outside of the company, and the more services that are reusable from system to system, the more ROI from our SOA. Second is the ability to change the IT infrastructure faster to adapt to changing needs of the business. This, of course, provides a huge st We implement SOA for two major reasons. First is the ability to save development dollars through reuse of services. These services may have been built inside or outside of the company, and the more services that are reusable from system to system, the more ROI from our SOA. Second is the ability to change the IT infrastructure faster to adapt to changing needs of the business. This, of course, provides a huge strategic advantage and thus allows for the business to have better chances of survival long-term. While determining the ROI on agility is difficult to figure out in hard dollars, we know the value is there. Under the concept of service reuse, we have a few things we need to determine to better define the value. These include: • The number of services that are reusable. • Complexity of the services. • The degree of reuse from system to system. The number of reusable services is the actual number of new services created, or, existing services abstracted, that are potentially reusable from system to system. The complexity of the services is the number of functions or object points that make up the service. We use traditional functions or object points as a common means of expressing complexity in terms of the types of behaviors the service offers. Finally, the degree of reuse from system to system is the number of times you actually reuse the services. We look at this number as a percentage. Agility is a strategic advantage that is difficult to measure in hard dollars, but not impossible. We first need to determine a few things about the business, including: • The degree of change over time. • The ability to adapt to change. • Relative value of change. The degree of change over time is really the number of times over a particular period that the business reinvents itself to adapt to a market. Thus, while a paper production company may only have a 5 percent degree of change over a 5 year period, a high technology company may have an 80 percent change over the same period. The ability to adapt to change is a number that states the company’s ability to react to the need for change over time: The notion being that the use of an SOA provides a better ability to change IT to adjust to needed changes in the business. Finally, the relative value of change is the amount of money made as a direct result of changing the business. For instance, a retail organization’s ability to establish a frequent buyer program to react to changing market expectations, and the resulting increases in revenue from making that change. Software Development