From:
Ken Laskey [mailto:klaskey@mitre.org]
Sent: Tuesday, September 06, 2005
11:40 AM
To: soa-rm@lists.oasis-open.org
Subject: RE: [soa-rm] Amazon.com
and Hurricane Catrina - Service Context? Service "Veneer"?
The actual collection (orchestration?) of services (or more basically,
capabilities that the services access?) will reflect the particular business
process, but at a reference model level we can't build a different model for
each business process. The challenge is to identify the concepts from
which you can support any business process. (Question: have the previous
drafts of SOA-RM missed any of these concepts?) A previous difficulty
when looking at typical use cases is that not every SOA challenge will have a
purchase order and a credit card number. While purchasing is an important
use case, a SOA tailored to support the variations of purchasing may fail badly
in addressing, say, the need to find and access real time disaster data.
Ken
At 11:23 AM 9/6/2005, marchadr@wellsfargo.com wrote:
I tend to agree with Steve's point about
having the model reflect the business processes and then deriving the service
definition from the type of processes the service will aggregate or use. In
theory, the payment of a product, service or donation is not that different
since at the end of the day it becomes a transaction of a total amount from one
account to the other (Amazon's in this case) and the entities (product,
service, or donation) are a means to an end.
The
separation of the order versus the purchasing would probably be the best
approach for the interface design, since the order could vary and have
polymorphistic behavior depending on the type of entities that are a part of
the order. (In some cases, the order would have a possibility of having a
donation and a product in the same order from the UI point of view.) The
order would be used to hold products and start the back office processing,
while the purchase would make the transaction of money based on a total amount
of the order.
This brings
up an issue in some ways of whether or not the order triggers the purchase
which would result in a service invoking another service.
The other issue I have been finding is a return is similar to a purchase since
it is the reverse of the transaction (one account to another with an amount),
since usually it is to late to reverse it before it actual makes a charge. Also
in the case of purchasing large amounts of products and paying for them and in
some back office process one product is determined to be discontinued then the
reversal of a transaction will really be based on the amount of that
discontinued transaction and not the total amount which would almost be like
purchasing the product back from the customer.
Something to
think about. The context seems to be a good approach for the ordering and
purchasing scenario.
Dan
-----Original Message-----
From: Jones, Steve G [
mailto:steve.g.jones@capgemini.com]
Sent: Monday, September 05, 2005
7:30 AM
To: Ken Laskey; SOA-RM
Subject: RE: [soa-rm] Amazon.com and Hurricane Catrina - Service
Context? Service "Veneer"?
I’ve
found that the only way to model this is to ensure that you have a hierarchy of
service that models the full business rather than concentrating on the technical
delivery elements. So you must model (but not have to directly
implement) the two types of services, which then act as containers for the
technical services. The higher order service then has different business
processes that give different results, but these are hidden from the service
consumers.
What has been
the biggest problem for me has been how to represent the change in contract
(but not interface) of a service due to its different domain. This
isn’t a huge technical challenge at the moment (as we can’t define
contracts at all!) but could become a much bigger challenge is future.
Some concept of contract inheritance might work here…
I’m wary
of describing groups as things (like a payment service) as a capability rather
than a service as it gets tricky on granularity, unless you mean that a
capability is a single invocation on a service?
If we deal in
RM around Service boundaries and the concept of hierarchy then we don’t
have a new service just a different context. Where it gets tricky for me
is when you have a service that IS clearly re-used but is actually completely
separate. You get this in some compliance sensitive areas where they use
identical solutions but completely separate instances. This is different
to ones where they do that just because they can, there is a broader context
that means they MUST be kept separate… a real bugger to model.
In part
I’m interested in how we are putting hierarchy into the RM?
Steve
From: Ken Laskey [ mailto:klaskey@mitre.org]
Sent: 05 September 2005 15:12
To: SOA-RM
Subject: Re: [soa-rm] Amazon.com
and Hurricane Catrina - Service Context? Service "Veneer"?
Steve,
I believe we are saying
the same thing. If the service is specifying the item to be purchased by
UPC, it is the same service in a different context. In this case, the
donation would be added to the general catalog and the user interaction would
be the same. I'd consider the "broader service" to be what I
call the underlying capability, i.e. the money collection in return for
something. The consumer sees the real world effect of that capability
existing and there being a service to access it, but never sees the capability
itself.
However, note that with
both Amazon and Apple there are new means to invoke the service (special links)
and the service interacts with the consumer in ways different than the
usual. For these reasons I'd say that for the new context Amazon and
Apple created new services (where here I mean services in the SOA context) to
repurpose existing capability (the provisioning of which may be called a
service in the more general business context). I'm not sure what Amazon
and Apple did made use of any SOA magic but it was nice reuse of capability.
Does this bugger things
up? I think it does only if we need to be definitive when you cross the
line from reusing a service to having a new one. I'm not sure for the
SOA-RM that we need to draw that line or even acknowledge that it may exist.
Ken
On
Sep 5, 2005, at 4:37 AM, Jones, Steve G wrote:
Again not to
raise old threads… but
This for me is
the concept of context, the context has changed which means the impact of the
service is different, its implementation and execution may however remain
identical. So the “Collection” service in this case always
results in Money being taken and added to a general leger with a UPC for the
product code (for example). The difference is that in the charity domain
it results in the further sending of that money onto the charity represented by
the UPC, whereas in the purchasing domain you get a song to download. The
actual collection service therefore remains unchanged but there is a broader
service (whose interface you don’t directly see but assume) which
controls the whole process.
And I can
safely say that these things can be a bugger to model.
From: Ken Laskey [mailto:klaskey@mitre.org]
Sent: 05 September 2005 01:29
To: SOA-RM
Subject: Re: [soa-rm] Amazon.com
and Hurricane Catrina - Service Context? Service "Veneer"?
And the answer, as
always, is it depends. In my example of buying by UPC symbol, it is the
same but possibly because the use of the UPC symbol has been expanded. In
the case of having a new service that, let's say, automatically substitutes the
charity item number for your choice of a song item number and maybe gives
specialized feedback to the consumer saying thank you for responding to the
hurricane emergency, I'd say it is a different service. It is derived from the
original but I'd say it is different.
Ken
P.S. and with this busy
hurricane season, we are up to Katrina.
P.P.S. Another interesting
aspect is if you had a computer that hadn't already accepted the iTunes terms
and conditions, you were first presented with their click-through agreement
before you contribute. So we also have an interesting reuse of policy and
the need to form a contract.
On Sep 4, 2005, at 7:14
PM, Chiusano Joseph wrote:
<Quote>
Is there also
a concept of a service having the same interface but by operating in a
different domain (e.g. charity) it acts different for the same interface?
</Quote>
Which raises
another question we've been through before in the TC (several months ago): Is
it the same service in both cases? That is, are the "normal"
Amazon.com order placement service (with credit card info on file, and
selectable each time) and this new "hurricane donation" service
really the same service?
Joe
P.S. Not
trying to resurrect a permathread - just tying a recent observation in with a
past exchange, to see it in a new light.
From: Jones, Steve G [ mailto:steve.g.jones@capgemini.com]
Sent: Sun 9/4/2005 5:25 PM
To: Ken Laskey; Chiusano Joseph
Cc: SOA-RM
Subject: RE: [soa-rm] Amazon.com and
Hurricane Catrina - Service Context? Service "Veneer"?
Is there also
a concept of a service having the same interface but by operating in a
different domain (e.g. charity) it acts different for the same interface?
In effect its business contract is changed by a business driver outside of its
scope, while its functionality (collecting money) remains the same its
imperative is changed by the wider business context in which it now sits.
Steve
From: Ken Laskey [mailto:klaskey@mitre.org]
Sent: 04 September 2005 21:22
To: Chiusano Joseph
Cc: SOA-RM
Subject: Re: [soa-rm] Amazon.com
and Hurricane Catrina - Service Context? Service "Veneer"?
Apple also did this with
their iTunes Music Store: click the link and you order a donation instead of a
song.
This is why I keep
insisting on differentiating between the service and the capability. The
underlying capability is to collect money for a purpose. The service
provides the interface for doing that. Typically, you invoke the
capability through a service that enables you to buy a book (or a song) but a
new service invokes that capability (with a new user facing interface for
Apple; I haven't checked Amazon) to "buy" a donation. The power
is the capability is reusable by making it accessible through a different
service.
Now note if I buy
something through a service that allowed me to specify the UPC code, I could
buy a donation through their existing service with that UPC, i.e. reusing the
service for a purpose similar to but different from its original purpose.
In fact, several supermarkets around here do support that because they have
little tear-off tablets at the checkout for certain hunger organizations and
you can hand the clerk a page for $1, $5, or $10.
Many interesting variations
and our RM just has to capture the concepts that can describe any of
them. I think I'll mow the lawn and think about this some more.
Ken
On Sep 4, 2005, at 4:06
PM, Chiusano Joseph wrote:
One thing that I
discovered regarding the horrible catastrophe in the Southern US is that
Amazon.com enabled people to use its online ordering service to make a
donation. One could use the credit card information that Amazon.com already had
online to make a donation in what it called "1-Click Donation" (or
something similar).
So instead of placing an
order for a book, CD, etc., your "order" was your donation, and you
could view your "order" online, which (as I recall) would show the
amount that you donated.
Something that came to my
mind is: What would this placing of a "new face" on a existing
service be called? Is it a different context for the ordering service? (i.e. in
the context of Hurrican Katrina) Is it a "veneer" that was placed on
top of the existing service? None of the above?
Joe
Joseph Chiusano
Booz Allen Hamilton
O: 703-902-6923
C: 202-251-0731
Visit us online@ http://www.boozallen.com
---
Ken Laskey
MITRE Corporation, M/S
H305 phone: 703-983-7934
7515 Colshire Drive
fax: 703-983-1379
McLean VA 22102-7508
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Ken Laskey
MITRE Corporation, M/S
H305 phone: 703-983-7934
7515 Colshire Drive
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McLean VA 22102-7508
This
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read, print, retain, copy, disseminate, distribute, or use this message or any
part thereof. If you receive this message in error, please notify the sender
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Ken Laskey
MITRE Corporation, M/S
H305 phone: 703-983-7934
7515 Colshire Drive
fax: 703-983-1379
McLean VA 22102-7508
This message contains
information that may be privileged or confidential and is the property of the
Capgemini Group. It is intended only for the person to whom it is addressed. If
you are not the intended recipient, you are not authorized to read, print,
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If you receive this message in error, please notify the sender immediately and
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/ Ken
Laskey
\
| MITRE Corporation, M/S H305
phone: 703-983-7934 |
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fax: 703-983-1379 |
\ McLean VA 22102-7508
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