When Integration Server executes a service, it must load the class that contains that service. To load the class, Integration Server follows the standard class loading delegation model. The current class loader defers the search to its parent class loader. If the parent class loader does not have access to the class, it defers to its parent. This process continues up the chain until it reaches the OSGi bundle class loader. Once control passes to the OSGi bundle class loader, it follows the class loader rules defined in the OSGi standard.