Section 4.4, Policies and Contracts Model, has
been written to incorporate the bare essentials of the decomposition of policies
and contracts such that the essentials are true to any SOA system. With that
said, the section does need a revision to be in synch with the latest changes to
the document.
The RA currently states:
"a policy is an
enforceable constraint or condition on the use, deployment, or description of an
owned entity as defined by any participant. A contract is a constraint that has
the agreement of the constrained participants."
Qualifying Policies and
Contracts beyond this means pushing a particular understanding of a policy or
contract specific to a particular system need. If someone states a counter
example of the use of policies and contracts that would invalidate a constraint
in the RA on policies and contracts, then that is a good test that the
qualification should not be in the RA.
Yes a policy is a prerequisite
for a contract in that a contract is a policy that is an agreement. Are people
looking for a check list of how contracts are used in a SOA? The possibilities
are infinite.
Danny
-----Original Message-----
From: "James
Odell" <>
Sent: Saturday, April 11, 2009 7:03pm
To:
Subject: Re:
[soa-rm-ra] SOA-RA(F) reorganization
Hi Frank,
Hmmm. While the
two ³the enforcement of the two is fairly closely aligned²
-- contracts are
not necessary for Policies, only the other way around.
Policies, IMO should
stand alone on their own. The CEP folks argue that
policies and events are
³fairly closely aligned². I can name a half dozen
other areas that could
say the same. The bottom line is that: Policy is a
concept that may be
necessary, but not sufficient for other areas.
Therefore, I strongly support
its own sub-section.
-Jim
On 4/11/09 6:11 PM, "Francis McCabe"
indited:
> Hi Jim
> Thank you for taking a look.
> As far as policies go, we have havered a little (to use a
Scottish-ism) on
> how to organize it. In the
RM work we closely identified the two -- with the
> distinction being that contracts are agreed to and policies
are asserted. Once
> you have either one, the
enforcement of the two is fairly closely aligned.
> Frank
> On Apr 11, 2009, at 2:46 PM, James Odell
wrote:
>
>> Hi all,
>>
>> After yet another reading of the SOA-RA
(Foundation?) and having sat through
>> the
recent spate of meetings, I have the following say about the
>> reorganization of the SOA-RA:
>>
>> Overall, I
think that the chapters and topics are sequenced in a coherent
>> and logical manner. Perhaps, it is because I read it too
many times now.
>> But, I don¹t think so.
>> Also, I understand the need to minimize
the amount of work needed on the
>> SOA-RA
at this point in its development. We need to get it released for
>> public comment ‹ without compromising
quality and understandability, of
>>
course.
>> Having said this, the only
thing that bothers me enough to suggest a
>> reorganizational change is the area of
Policies:
>>
>> 1) Policies, in general, are depicted in document far
earlier than they are
>> finally addressed
(by 40-50 pages). Since policies ‹ IMO ‹ are an important
>> ingredient in the SOA-RA, I would like to see them
addressed earlier. (My
>> personal opinion
is that policies are not mentioned anywhere near the amount
>> that they should. For example, they are used in events,
composition of
>> services, roles, and
organizations. However, since this would involve
>> additions to the current document, I will not push this)
>>
>> 2) I strongly dislike grouping the entire topic with
contracts. While
>> policies are used for
contracts, Policy is a standalone concept ‹ which
>> neither depends on nor is used solely with Contract.
(Even the OMG and W3C
>> treat policies as
a separate notion.) Why is this reasonable? Because
>> policies are used in a variety of situations ‹ only one
of which is
>> contracts. By placing
Policies in lock step with (and almost subordinate to)
>> with Contracts is not appropriate, IMO.
>>
>> 3) My
suggestion: separate Policies and Contracts into two distinct
>> subsections (e.g., 4.4 and 4.5).
>>
>> In short, this
would provide clarity for the notion of Policy and not
>> require much change to the current
document.
>>
>>
>> All the
best,
>>
>> Jim
>>
>
>
-----Original Message-----
> From: "James Odell" <>
> Sent: Saturday, April 11, 2009 7:03pm
> To:
> Subject: Re:
[soa-rm-ra] SOA-RA(F) reorganization
>
> Hi Frank,
>
> Hmmm. While the
two ³the enforcement of the two is fairly closely aligned²
> -- contracts are
not necessary for Policies, only the other way around.
> Policies, IMO should
stand alone on their own. The CEP folks argue that
> policies and events are
³fairly closely aligned². I can name a half dozen
> other areas that could
say the same. The bottom line is that: Policy is a
> concept that may be
necessary, but not sufficient for other areas.
> Therefore, I strongly support
its own sub-section.
>
> -Jim
On 4/11/09 6:11 PM, "Francis McCabe"
indited:
> Hi Jim
> Thank you for taking a look.
> As far as policies go, we have havered a little (to use a
Scottish-ism) on
> how to organize it. In the
RM work we closely identified the two -- with the
> distinction being that contracts are agreed to and policies
are asserted. Once
> you have either one, the
enforcement of the two is fairly closely aligned.
> Frank
> On Apr 11, 2009, at 2:46 PM, James Odell
wrote:
>
>> Hi all,
>>
>> After yet another reading of the SOA-RA
(Foundation?) and having sat through
>> the
recent spate of meetings, I have the following say about the
>> reorganization of the SOA-RA:
>>
>> Overall, I
think that the chapters and topics are sequenced in a coherent
>> and logical manner. Perhaps, it is because I read it too
many times now.
>> But, I don¹t think so.
>> Also, I understand the need to minimize
the amount of work needed on the
>> SOA-RA
at this point in its development. We need to get it released for
>> public comment ‹ without compromising
quality and understandability, of
>>
course.
>> Having said this, the only
thing that bothers me enough to suggest a
>> reorganizational change is the area of
Policies:
>>
>> 1) Policies, in general, are depicted in document far
earlier than they are
>> finally addressed
(by 40-50 pages). Since policies ‹ IMO ‹ are an important
>> ingredient in the SOA-RA, I would like to see them
addressed earlier. (My
>> personal opinion
is that policies are not mentioned anywhere near the amount
>> that they should. For example, they are used in events,
composition of
>> services, roles, and
organizations. However, since this would involve
>> additions to the current document, I will not push this)
>>
>> 2) I strongly dislike grouping the entire topic with
contracts. While
>> policies are used for
contracts, Policy is a standalone concept ‹ which
>> neither depends on nor is used solely with Contract.
(Even the OMG and W3C
>> treat policies as
a separate notion.) Why is this reasonable? Because
>> policies are used in a variety of situations ‹ only one
of which is
>> contracts. By placing
Policies in lock step with (and almost subordinate to)
>> with Contracts is not appropriate, IMO.
>>
>> 3) My
suggestion: separate Policies and Contracts into two distinct
>> subsections (e.g., 4.4 and 4.5).
>>
>> In short, this
would provide clarity for the notion of Policy and not
>> require much change to the current
document.
>>
>>
>> All the
best,
>>
>> Jim
>>
>
>
