Cloud Computing and SOA Convergence in Your Enterprise: A Step ...

150 Chapter 8 Bringing Governance to the Clouds
Policies
Policies
Runtime
Governance
Monitoring
Repository
Logs
Figure 8.3 Governance means controlling access to service using policies, tracking
services using repositories, and logging and monitoring the execution of those
services.
Thus, we create something that has a tremendous amount of value when
it comes to agility and the ability to operate enterprise IT at greatly reduced
costs. However, the architecture is very complex and needs a specialized service
governance mechanism to manage this complexity.
Dependencies, as reflected in our opening example, mean that many of
these services are interdependent: services call other services, which make
them composite services. Moreover, many applications are dependent on
these services (see Figure 8.4).
Services that fail or, more likely, that change without authorization have
a domino effect on other services and applications that leverage them. A single
service that is altered without the knowledge and understanding of the
impact that change may have could bring down many core enterprise systems,
perhaps costing thousands of dollars an hour in lost revenue, which