Branimir Valentic By providing IT services, a service provider creates value that a customer receives. To avoid a gap between (customer) expectations and reality (of how services are provided), the value created should be measured. There are several ways, i.e. parameters, of how this can be done. Availability of the service is just one of them.
It’s simple – we agree with the customer as to a certain service level, which includes targeted availability, and then we measure (availability) achievement. Easy to say, but how does it work in practice?
In real wor(l)ds
It is important to say – availability of services significantly shapes customer satisfaction (or dissatisfaction). I assume that I don’t have to explain the negative effects of unavailable service. Therefore, both service providers and customers need plain numbers that will provide information about service availability. In addition to service availability, some components (or Configuration Items – CIs) that form the service will be measured, and their availability parameters analyzed and reported. All this implies that availability must be managed.
Availability management is about monitoring, measuring, analyzing and reporting of the following aspects:
- Availability –the ability of the service or component to provide the agreed-upon functionality when required. You will find it expressed in percentage (%), e.g. service has availability of 99.95 %. It is calculated as follows:
- Reliability – expressed in hours (e.g. 2.600 h), it measures how long a service or component can fulfill its function without interruption. You will find two parameters that measure reliability:
- Maintainability – measures how quickly a service or component can be restored to normal operation after a failure (e.g. 10 h). It is calculated as follows:
- Serviceability – the ability of a third party to fulfill obligations expressed in agreed levels of availability, reliability and maintainability. Using these measurements, you can assure that your suppliers are performing as agreed.
My experience is that Service Level Agreements (SLAs) usually define only availability requirements, and rarely reliability and maintainability.
Integration with Incident Management
So, service incidents happen. Is that the end? It shouldn’t be. One of the principles of Availability management is that customer satisfaction can still be achieved, even if incidents occur. How? By assisting Incident Management to ensure that incidents are resolved as quickly as possible and that the impact of incidents is minimized.