They generally supplement infrastructure services, and over time they will be accessed through portals, but they may also be accessed directly by internal applications and services, as well as by partners, suppliers, and customers.
Business services are consumers of other business services as well as infrastructure services.
As a result of the number of interfaces, business services require a rich development environment that supports development with many APIs, as well as support for managing transaction and security state. Tips for Designing Business Services Distributed Java technology objects and XML are emerging as important elements of interfaces for accessing business services across a wide range of platforms. Check to see whether standard schemas can accommodate the types of activities you are designing for, and leverage them whenever possible. Many organizations have efforts underway to standardize representations of common business activities in XML and Java technology. If users or other organizations will be accessing the service directly, pay special attention to interface design, especially around security.