Re: [soa-rm-ra] Comments on Needs and Capabilities

From
Michael Stiefel <>
Date
2006-07-05T14:36:05+00:00
ID
Thread
Re: [soa-rm-ra] Comments on Needs and Capabilities
Yes, the phrase "SOA deciding" is a bit too anthropomorphic. I
changed it to "the implementers  of a SOA". That does
sound better.

Michael

At 01:12 AM 7/4/2006, Ken Laskey wrote:

I'd think the third paragraph
(with a few edits) expresses an important point that isn't covered
elsewhere.

Formally, capabilities are found by a service consumer
because they are currently, or will become visible.
The visibility may be through a
description of the capability (where access by means of a service would
be included in the description) or a service description (where the real
world effects imply the underlying capabilities.) 
But how does a given SOA decide what capabilities are
needed? [not sure if "SOA
deciding" is the way I'd phrase it.]  Some
parts of a SOA are capability-driven because an organization has certain
capabilities that it wishes to expose. Other parts are need-driven
because an organization has certain needs, and wishes to make those
visible in order to find those organizations that have, or are willing to
build, services that meet those needs. Need-driven capabilities might be
built specifically for a given situation, or they might be dynamically
created.

In thinking about the fourth paragraph, should we note that a big
part of bringing needs and capabilities together in an SOA requires
aligning policies and resolving policy differences?

Finally, in looking at what it means for a need to be satisfied by a
capability, satisfying is not built on expectations of effect but on
actual RWEs.  I chose a capability based on expectations but my
satisfaction is how well the RWEs meet those expectations.

Ken

On Jul 1, 2006, at 12:47 AM, Danny Thornton wrote:

As I look at the different
sections of the RA

architecture, I like to ask myself how this helps me

move to a more concrete architecture.  The "Needs and

Capabilities" section contains references to

visibility in the SOA, discussion of contracts and

possible Service Level Agreements, references the

execution  context, references semantics, discussion

of the measurability of needs and capabilities and

expectations.

http://wiki.oasis-open.org/soa-rm/TheArchitecture/NeedsAndCapabilities

I do not believe that measurability of needs,

capabilities, and expectations are discussed in other

sections of the RA so I find this to be one of the key

discussion points for this section.  Frank discussed

measuring the need in terms of a proposition against

the shared state and the use of policies in that

measurability. 

Also, the point about an enterprise SOA having

policies and an internet SOA having contracts (I would

also add policies) was a good point to bring out. 

Danny

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Ken Laskey

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