Re: [soa-rm-ra] Groups - Modification of Policy_Contract_Business diagram (OASIS_Policy-Contract_Diagram.JPG) uploaded

[Francis McCabe <frankmccabe@mac.com>]

A quick follow up,

It is also not fair to say that a contract is *more* than a policy.

The distinction between them refers to the origin of the constraint:  
a policy originates with a single participant (or proxy etc.) a  
contract originates in an agreement between participants.


On May 5, 2007, at 11:07 AM, Francis McCabe wrote:

> Again, I need to get completely clear on something:
>
> It is *not* reasonable to state:
>
> Contract is not only more than a Policy but also more than a SLA
>
> In some limited areas, you may constrain SLAs to focus on things  
> like bandwidth etc., but other businesses will use SLAs to govern  
> things like business opening hours, response times for service and  
> so on.
>
> So, again, I do not yet see a particularly strong case for  
> distinguishing SLAs from contracts.
>
> Certainly for our architecture we need to be as encompassing as  
> required to support business via services, not simply to build yet  
> another IT infrastructure.
>
> Frank
>
> On May 5, 2007, at 10:53 AM, michael.poulin@uk.fid-intl.com wrote:
>
>> I have a strong impression that in our March discussion about  
>> Contract & Policies we  have agreed that Contract is not only more  
>> than a Policy but also more than a SLA. The SLA is explicitly  
>> measurable (run-time) set of service attributes/characteristics/ 
>> actions while a Contract can contain Commitments of the contract  
>> participants that 1) are not visible through the service  
>> interface; 2) may be not measured at run-time. I guess, it is the  
>> time for me to show my version of a Service Contract Template we  
>> are discussing in my organisation ( I will be able to do it not  
>> earlier than on Tuesday next week).
>>
>> I have described an example of such contract  in my article "Does  
>> Web Services makes a Service for SOA?" In particular, a service  
>> provider was obliged to gather audit info on all actions requested  
>> by particular client and failed in it because its database was not  
>> available for some time and several audit messages got lost.
>> If we are building high level RA, we cannot discard the scenario  
>> I've just described.
>> That is, Contract is an agreed container of all service related  
>> actions performed by the provider's SW system(s). With such  
>> definition, I do know what to do in IT with Service Contract.
>>
>> Nevertheless, I am still unclear on Contract-Policy relationship  
>> issue...
>>
>> - Michael
>