Types of testing

The following types of test are used to verify that the service meets the user and customer requirement s as well as the service provider ’s requirements for managing, operating and supporting the service. Care must be taken to establish the full range of likely users, and then to test all the aspects of the service, including support and reporting.

Functional testing will depend on the type of service and channel of delivery. Functional testing is covered in many testing standard s and best practice s (see Further information).

Service testing will include many non-functional test s. These tests can be conducted at several test levels to help build up confidence in the service release. They include:

• Usability testing
• Accessibility testing
• Process and procedure testing
• Knowledge transfer and competence testing
• Performance, capacity and resilience testing
• Volume, stress, load and scalability testing
• Availability testing
• Backup and recovery testing
• Coherency testing
• Compatibility testing
• Documentation testing
• Regulatory and compliance testing
• Security testing
• Logistics, deployability and migration testing
• Coexistence and compatibility testing
• Remediation, continuity and recovery testing
• Configuration, build and installability testing
• Operability and maintainability testing.

There are several types of testing from different perspectives, which are described below.

Service requirements and structure testing – service provider, users and customers

Validation of the service attribute s against the contract, service package and service model includes evaluating the integration or ‘fit’ of the utilities across the core and supporting service s and service assets to ensure there is complete coverage and no conflicts.

Figure 4.31 Designing tests to cover range of service assets, utilities and warranties

Figure 4.31 shows a matrix of service utility to service reporting and the service asset s that support each utility. This matrix is one that can be used to design the service tests to ensure that the service structure and test design coverage is appropriate. Service tests cases are designed to test the service requirement s in terms of utility, capacity, resource utilization, finance and risks. For example approaches to testing the risk of service failure include performance, stress, usability and security testing.

Service level testing – service level managers, operations managers and customers

Validate that the service provider can deliver the service level requirement s, e.g. testing the response and fix time, availability, product delivery times and support services.

The performance from a service asset should deliver the utility or service expected. This is not necessarily that the asset can deliver what it should be capable of in its own right. For example a car’s factory specification may assert that it is capable of 150kph, but for most customers delivering 100kph will fully meet the requirement.

Warranty and assurance tests – fit for use testing

As discussed earlier in this section, the customers see the service delivered in terms of warranties against the utilities that add value to their assets in order to deliver the expected business support. For any service, the warranties are expressed in measurable terms that enable tests to be designed to establish that the warranty can be delivered (within the agreed degree of confidence). The degree of detail may vary considerably, but will always reflect the agreement established during Service Design. In all cases the warranty will be described, and should be measurable, in terms of the customer’s business and the potential effects on it of success or failure of the service to meet that warranty.

The following tests are used to provide confidence that the warranties can be delivered, i.e. the service is fit for use:

• Availability is the most elementary aspect of assuring value to customers. It assures the customer that services will be available for use under agreed terms and conditions. Services are expected to be made available to designated user s only within specified areas, locations and time schedules.
• Capacity is an aspect of service reporting that assures the customer that a service will support a specified level of business activity or demand at a specified level of service quality. Customers can make changes to their utilization of services while being assured that their business process es and system s will be adequately supported by the service. Capacity management is a critical aspect of Service Management because it has a direct impact on the availability of services. The capacity available to support services also has an impact of the level of service continuity committed or delivered. Effective management of service capacity can therefore have first-order and second-order effects on service warranty.
• Continuity is the level of assurance provided to customers that the service will continue to support the business through major failure s or disruptive event s. The service provider undertakes to maintain service asset s that will provide a sufficient level of contingency and responsiveness. Specialized systems and processes will kick in to ensure that the service level s received by the customer’s assets do not fall below a predefined level. Assurance is also provided that normal service levels will be restore d within a predefined time limit to limit the overall impact of a failure or event. The effectiveness of service continuity is measured in terms of disturbance to the productive state of customer assets.
• Security assures that the utilization of services by customers will be secure. This means that customer assets within the scope of service delivery and support will not be exposed to certain security risks. Service providers undertake to implement general and service-level controls that will ensure that the value provided to customers is complete and not eroded by any avoidable costs and risks. Service security covers the following aspects of reducing risks:
• Authorized and accountable usage of services as specified by customer
• Protection of customers’ assets from unauthorized or malicious access
• Security zones between customer assets and service assets
• Plays a supporting role to the other three aspects of service warranty
• When effective has a positive impact on those aspects.

Service security inherits all the general properties of the security of physical and human asset s, as well as intangibles such as data, information, coordination and communication.

Usability – users and maintainers

Usability testing is likely to be of increasing importance as more services become widely used as a part of everyday life and ordinary business usage. Focusing on the intuitiveness of a service can significantly increase the efficiency and reduce the unit cost s of both using and supporting a service.

User accessibility testing considers the restricted abilities of actual or potential users of a new or changed service and is commonly used for testing web services. Care must be taken to establish the types of likely users, e.g. hearing impaired users may be able to operate a PC-based service but would not be supported by a telephone-only-based service-desk support system. This testing might focus on usability for:

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