Web Services Platform Architecture [Electronic resources] : SOAP, WSDL, WS-Policy, WS-Addressing, WS-BPEL, WS-Reliable Messaging, and More نسخه متنی

1.1. Virtual Enterprises

Most Ley 2000]) translate directly into actions that are necessary to alter business processes: changing the flow of activities of a business process, changing the actors who are performing these activities, changing the tools that support these activities, and so on. These might result in moving the execution of (a subset of) the activities of the business processes to partners. The result could be multiple business partners having to cooperate to perform the business processes of a given company. The company in fact becomes a virtual company (or virtual enterprise). This term indicates that externally, the company looks like a real companyperforming all of its business processes itselfbut in practice, that is not what is actually happening. Others are partially running the company's business processes, making the company virtual in this sense.

1.1.1. Business Process Optimization

The model of a business process prescribes the order in which a business must execute the activities that constitute it and under which conditions it must perform each of the activities. Collectively, this kind of prescription is called control flow. The control flow massively influences business-relevant properties of a business processsuch as its total cost and its overall durationand thus the competitiveness of a company:

• The execution of each step or activity within a business process is associated with certain costs, such as people costs that are associated with the activity if human intervention is required, or the cost of computer resources that are required to execute activities within the IT environment. Based on this information, a company can derive the overall cost for performing a business process. For example, if policy associated with a credit allocation process determines that someone must check credits with an amount greater than $1,000, and more customers are asking for credits above this limit, a business could change the policy to set manual intervention at a higher value to reduce the overall costs for running the process.

• Activities have temporal characteristics, such as the average duration for executing an activity or the average time elapsed until an activity is picked up and performed. Based on this information, you can derive the average interval for executing a business process. For example, when you are booking a business trip, you can reserve hotel and flight reservations in parallel, resulting in a shorter execution time for the overall business process relative to its sequential execution.

There are other business-relevant Ley 2000]. Workflow systems allow monitoring of the business properties of individual business processes or aggregations of business processes at runtime. They also support the analysis of corresponding execution histories. Based on monitoring and analysis of results, you can change the model of a business process, if required, to further optimize it, especially when benchmarking shows that the execution of a business process is not competitive in terms of its key business parameters, such as cost or duration.

Sometimes, modifying the control flow of a business process is insufficient to hit the target values for certain business properties. For example, the cost structure within a company or wages for certain required staff might be too high to meet business expense targets. In such situations, a company's business process cannot gain competitiveness without significant re-engineering. The company (or a certain branch or location within a company) should probably determine its core competencies, focus on executing only the activities that correspond to these core competencies, and outsource the noncore competencies. Of course, the constraint is that outsourcing must result in hitting the target objectives of the subject business properties. SOA and Web service technology facilitates this kind of outsourcing in a secure, reliable manner.

1.1.2. Collaborations, Mergers, and Acquisitions

Figure 1-1 demonstrates an original process (denoted by "P") that a company runs. The company determines that it is no longer competitive in performing activities A, B, and E. It finds two partners that can run these activities and meet the business goals. Partner 1 runs activities A and B, and Partner 2 runs activity E. The company re-engineered the original process into a new process (P'). In the new process, activity AB kicks off the execution at the first partner (Partner 1), and E' starts the execution at the second partner (Partner 2). The company now has a new process P', which results in increased competitiveness.

In general, a company can work in several ways with partners that run the outsourced activities. One way is for a business to acquire a partner that can effectively run some of the activities that it could not run in a competitive manner before. A company might take this approach if the activities that it has trouble performing competitively are core to its business. A company might also choose this acquisition if it is cheaper to acquire the partner than pay the partner to perform the activities. A company might also choose to merge with a partner, essentially combining its own business with that of the partner in a peer manner. This could exploit synergies between the two companies, further reducing costs and enhancing the competitiveness of the aggregate. Usually, mergers and acquisitions result in business processes that are run in a Dan 2004]. The result is a network of collaborating partners.

Situations might be highly dynamic. Multiple partners might provide the same services, and a company should choose on a case-by-case basis one of these to perform specific activities. For example, the cost of performing activities on behalf of a company might change depending on the actual load at each partner side. The company can then determine the partner on a best-price basis.

Collaboration might not only result from process optimization endeavors, but from supply chains that are typical within an industry. In this situation, a company and its partners are not distinguished. All partners are peers, collaborating to realize an overall business process that is spread over the partners. Some industries even have standards to define the various kinds of partners, the activities each of them runs, and how they relate. For example, RosettaNet [RN] defines such a standard and is currently moving toward Web service technology [RNWS].

1.1.3. Resource Sharing

In addition Ley 2004], [Rappa 2004]). Within this utility computing model, computer resources and other IT related resources are offered in a similar manner to traditional utilities such as electricity or telephone. The usage of the utility IT resources to run parts of a business process is metered and charged on this basis. You will read more about this topic later.