Tom Graves has written extensively about the notions of services, functions, capabilities and assets as well as on how these interrelate and how to tell one from the other.
I strongly recommend reading the following blog posts by Tom:
- Assets and services
- Service, function and capability (again)
- Service, function and capability (an addendum)
The following is my interpretation of what I perceive to be the essence of these blog posts. I took the liberty to mix citing and paraphrasing his definitions or what they meant to me. In adapting this for my own work, I’m sure I lost some of the subtleties of Tom’s work. (If any of this doesn’t seem to make sense: Use the source, Luke!)
A service serves a purpose.
A service is a means for realising a desired end.
Services act on assets.
Services share and exchange assets with each other.
An asset is a resource for which a service exercises responsibility.
Services realise functions.
A function is an external view of a service.
Services are actioned by capabilities.
A capability is the ability to do something (appropriate with or on or for something or someone).
Capabilities combine three essential elements: action (think verb + object), actor (or an actor’s agent) and skill-level.
Services link functions and capabilities.
Services are triggered by events.
Services have location.
A process links services.
Some capabilities use processes.
Assets, events and locations can be described in terms of the tetradian dimensions (physical, virtual, relational, aspirational).
Everything in the enterprise can be viewed as a service.
The enterprise itself can be viewed as a service.
The enterprise and its elements described here (services, processes etc.) are layered and recursive: they are fractals.
Have I already said I strongly recommend reading Tom’s posts? Links above.
2013-05-21: Undid previous change and replaced with a summary statement saying that the enterprise and its element described herein are layered, recursive, fractal as per Tom’s follow-up comment below.
2013-05-20: Added “Services are fractals”, “Processes are fractals”, and “The enterprise itself can be viewed as a service” in response to Tom’s comment below.