# ITIL/Foundation/Service Management/Service composition

This lesson introduces the main definitions used to define a service components in Information Technology Infrastructure Library 2011.

## Objectives and Skills

Objectives and skills for this service composition section of ITIL Foundation include:
* Define the various components of a service

## Activities

* Review the key terms, then the questions below.
* Use the Discuss page to post comments and questions regarding this lesson.

## Key Terms

When setting up a new service, all of its components should be evaluated in order to ensure they will fulfil the current and potential future customer needs.

### Business process

A business process or business method is a collection of related, structured activities or tasks that produce a specific service or product (serve a particular goal) for a particular customer or customers. It often can be visualized with a flowchart as a sequence of activities with interleaving decision points or with a Process Matrix as a sequence of activities with relevance rules based on data in the process.
It could be defined as how to raise all the service functional needs.

### Core service

As already stated, the core service is what the customer has asked to his provider.

### Service design package

The purpose of Service Design Package, also called SDP, is to document each service requirements at all stages of its lifecycle.

### Business case

A business case captures the reasoning for initiating a project or task. It is often presented in a well-structured written document, but may also sometimes come in the form of a short verbal argument or presentation. The logic of the business case is that, whenever resources such as money or effort are consumed, they should be in support of a specific business need. An example could be that a software upgrade might improve system performance, but the "business case" is that better performance would improve customer satisfaction, require less task processing time, or reduce system maintenance costs. A compelling business case adequately captures both the quantifiable and unquantifiable characteristics of a proposed project.
The business cases provide what could be expected by the service in term of Return on Investment.

### Service level agreement

A service-level agreement (SLA) is a part of a service contract where a service is formally defined. In practice, the term SLA is sometimes used to refer to the contracted delivery time (of the service or performance). As an example, Internet service providers will commonly include service level agreements within the terms of their contracts with customers to define the level(s) of service being sold in plain language terms. In this case the SLA will typically have a technical definition in terms of mean time between failures (MTBF), mean time to repair or mean time to recovery (MTTR); various data rates; throughput; jitter; or similar measurable details.
By other words, it is a formal understanding with customer about the scope and the level of quality to provide.

### Service level requirement

A Service Level Requirement (SLR) is a broad statement from a customer to a service provider describing their service expectations. A service provider prepares a service level agreement (SLA) based on the requirements from the customer. For example: A customer may require a server be operational (uptime) for 99.95% of the year excluding maintenance.
It depicts the level required by the customer and that will be used to define the SLA.

### Infrastructure

Infrastructure is defined in ITIL as a combined set of hardware, software, networks, facilities, etc. (including all of the information technology), in order to develop, test, deliver, monitor, control or support IT services. Associated people, processes and documentation are not part of IT Infrastructure.
It covers all IT equipment (Servers, network, personal computers …); most of the services related to this are supporting services as they are not seen by the customer but needed to deliver the core service.

### Environment

The environment is what to be set up to let infrastructure provides the required level of service in a reasonable manner.

### Data

The data domain covers what needs to be collected or transferred in order to provide the core service.

### Application

Applications are all pieces of software used by the infrastructure to deliver the core service.

### Integration

Integration refers to the interaction between the various applications and the data they will need to carry in order, at the end, to deliver the core service in a level expected by the customer.

### Operational level agreement

An operational-level agreement (OLA) defines the interdependent relationships among the internal support groups of an organization working to support a service-level agreement (SLA). The agreement describes the responsibilities of each internal support group toward other support groups, including the process and timeframe for delivery of their services. The objective of the OLA is to present a clear, concise and measurable description of the service provider's internal support relationships.

### Supporting service

As previously stated, the supporting services are all the services not firmly required by the customer but that will be anyway needed to properly deliver the core service.

### IT process

IT processes are needed by the IT service provider to deliver successfully the core service as defined in the SLA.

### Function

As it will be described more in details further, the functions cover all internal teams in charge of supporting the various IT components.

### Roles

The role is the activity or responsibility provided to a team in order to control that resources are properly delivered to a service.

### Suppliers

The supplier is an external third party who will have to deliver support to any of the service component.