There are several fundamental measures that can be applied to decisions about the appointment of an application service provider (ASP) or web outsourcer. Systems must be: available, elastic, efficient, extendible, manageable, scalable and secure. To some extent these measures also apply to basic web hosting.

Available

The systems should be available to handle transactions at any time of day or night, for every day of the year.
Electronic, web-based business is global. It does not recognize any one country's national holidays or any one religion's festivals and holy days. Global businesses respect other people's religions, beliefs and heroes. The systems that enable that business to be global must ignore them.
Sufficient hardware, software and human interventions should be available to keep the systems running. Faults must be subject to business continuity management rather than disaster recovery. Where possible, tasks for switching to alternate processors and recovering data from backup or from mirror systems should be automated.

Elastic

The systems should be able to take short term increases in load.
Many organizations, including some ASPs, confuse elasticity with scalability. While scalability allows systems to handle sustained increases, elasticity allows systems to cope with short term increases. The differences are actually quite clear.
Scalability usually implies steady, planned, long-term growth. With scalability, a business can lift its traffic from 100 vistors per minute to 1,000, or beyond. So, a business can start with an expectation of 100 visiotrs per minute and then raise that expectation through actions such as scalability, increased advertising and reputation.
Elasticity covers sharp, short term increases that may not be sustained.
Systems need to have elasticity. Customers need to verify that they have elastic capacity available, especially if traffic increases for other customers of their service provider. There should not a situation of "robbing Peter to pay Paul".

Efficient

The systems must work efficiently.
Efficiency has impacts in a number of areas.

• In terms of time, it maximizes throughput, ensuring that contacts with other service providers, such as banks, are initiated and completed with minimal delays.
• In terms of information, it provides information at the right level of detail for each user.
• In terms of service, including the despatch of goods, it ensures that customers can track their purchases easily.
• In addition to these benefits of efficiency, the systems are probably based on a simple, optimized database design, using object oriented techniques and reusable components. These tend to be simple and fast.

Extendible

It must be possible to enhance a system's functions with relative ease.
Standard development languages assist, provided that the code meets the appropriate standards. The whims and fancies of individual software vendors should be avoided. As an example, no-one should be coding today using HTML tags which were only used by Microsoft's Internet Explorer and which were not accepted by the World Wide Web Consortium.
Object oriented design assists with making extensibility easy, especially when components are deployed.

Manageable

Systems must be manageable. There should be little technical overhead involved in adding new users or in extending a user's access to functions and data. The technical overhead can also be reduced in development and installation of applications, provided that capable application service providers (ASPs) or outsourcers have been engaged.

Scalable

Systems must be able to be expanded to handle long term, sustained increases in activity, transactions and data. Following an increase in the scale of the systems, the same functions should be available in the same times.

Secure

Security has traditionally been an inward-facing topic. Organizations have been keen to see that their own security and privacy were protected. Today, there is a much greater emphasis on keeping customers' information secure.
At another level, the customers of the service provider must be assured that their information and methods will be kept secure from their competitors.