How to define Service Availability

[fethy]

Dear all,
Need some help on defining service availability.
I have been calculating KPI for our company on service availability for a around 3 years now.
In our service catalog we've defined the different services we offer to business units and their relationships between them.
One month, an incident occured on the LAN service, which has impacted one of the business service (it wasn't available, cause the server has one network card).

So when I calculated the availability for this service, it wasn't 100% available due to the network incident.
My top management didn't agree with me, saying that the incident occured on the network and not the business service.
So for them, the business service was 100% available, but the LAN service had the availability reduced due to the incident.
There was a long debate on that, because I wasn't convinced.
Was my vision wrong?
If it's the case, how do we then define service availability?

Thanks in advance for your help.

[BorisBear]

It depends how you define Service........a question for service level management.

If its defined from a user perspective then you may well be right but I suspect your company is offering an application service, a network service, a data centre service, etc and wouldn't want to be hit twice on different service lines for the same outage.

[Diarmid]

Availability is always availability to the customer and service is always service to the customer. Although Boris is correct, the idea that there is not a direct offer of availability of a business service (like an application) to the customer is somewhat strange and I'm sure the customer cares not a whit what component of the infrastructure caused the lack of availability. I worked in a place where they got clever about de-constructing real services and I thought it very poor at the time.

I believe that such a set up shows a lack of business focus in the IT department, i.e. what Ian Clayton calls "inside-out" thinking.

For my money, it only helps to talk about things like a network service etc. when there is an intermediate customer (such as the service delivery manager. Then you have unavailability of network from Network Management to Service Management and unavailability of application from Service Management to business customer. Both hits are correct and should be dealt with according to the appropriate SLAs OLAs or contracts.

Without the intermediate service customer you get nonsense and if I were your customer I would claim both hits since you offered both services and failed to deliver each.
_________________
"Method goes far to prevent trouble in business: for it makes the task easy, hinders confusion, saves abundance of time, and instructs those that have business depending, both what to do and what to hope."
William Penn 1644-1718