Re: Ignorable assertions and interoperability

Hi

I think I agree that perhaps it's more the issue of understanding the reality and setting the expectation bar properly, depending on what kind of consumers are working in a given environment, etc.... That's why I believe it would help adding your earlier statement to the primer's section on Ignorable assertions [1] as it will make the message clearer to policy authors.

Thanks, Sergey
[1] http://www.w3.org/Bugs/Public/show_bug.cgi?id=4339

  ----- Original Message ----- 
  From: Christopher B Ferris 
  To: Sergey Beryozkin 
  Cc: public-ws-policy@w3.org ; public-ws-policy-request@w3.org 
  Sent: Wednesday, February 21, 2007 1:20 PM
  Subject: Re: Ignorable assertions and interoperability



  I see now what you mean. However, IMO, this isn't an interoperability issue, as much as one of 
  understanding the reality that despite the fact that a policy provider might mark something as 
  ignorable, there will always be some policy consumers that will ignore that advice:-) 

  I guess it is a matter of expectation setting. 

  Cheers, 

  Christopher Ferris
  STSM, Software Group Standards Strategy
  email: chrisfer@us.ibm.com
  blog: http://www.ibm.com/developerworks/blogs/page/chrisferris
  phone: +1 508 377 9295 

  "Sergey Beryozkin" <sergey.beryozkin@iona.com> wrote on 02/21/2007 08:01:13 AM:

  > Hi Chris 
  >   
  > "I guess I don't understand why strict mode presents interoperability 
  > challenges. We have both strict and lax mode intersection for a reason. 
  > Those policy consumers that don't want to ignore assertions that are 
  > marked as ignorable can use strict to achieve that objective. Those that 
  > are okay with ignoring what is marked ignorable can use lax mode. The 
  > policy consumer has the choice to do whatever they feel is right for 
  > their circumstances. " 
  >   
  > I agree. From the consumer's perspective we have no issues at all. 
  > The things are slightly different from the provider's perspective though. 
  > Provider marks the assertion as wsp:ignorable=true so that it can be
  > ignored for the intersection purposes. Otherwise why else would the 
  > provider do it ? If the provider wants the assertion be understood 
  > always then it would just expose that assertion as the normal 
  > required assertion. 
  > But the provider does not aware of what mode consumers will be 
  > using. By marking the assertion as ignorable the provider can get 
  > some consumers fail to consume the service if they work in the 
  > strict mode. Yes, that's what consumers chose to but I think it's 
  > not something a provider will really want... So it's a possible 
  > interop concern at the WS-Policy level 
  >   
  > Do you see what I mean ? Would you agree ? 
  >   
  > Cheers, Sergey 
  >   
  > 
  > ----- Original Message ----- 
  > From: Christopher B Ferris 
  > To: Sergey Beryozkin 
  > Cc: public-ws-policy@w3.org ; public-ws-policy-request@w3.org 
  > Sent: Wednesday, February 21, 2007 12:32 PM 
  > Subject: Re: Ignorable assertions and interoperability 
  > 
  > 
  > Sergey, 
  > 
  > Thanks for elaborating. 
  > 
  > Please see my inlined comments below. 
  > 
  > Cheers, 
  > 
  > Christopher Ferris
  > STSM, Software Group Standards Strategy
  > email: chrisfer@us.ibm.com
  > blog: http://www.ibm.com/developerworks/blogs/page/chrisferris
  > phone: +1 508 377 9295 
  > 
  > public-ws-policy-request@w3.org wrote on 02/21/2007 04:36:19 AM:
  > 
  > > Hi Chris 
  > >   
  > > Thanks for your comments. 
  > >   
  > > I agree, I should've created a bug with a specific proposal rather 
  > > just suggesting (the editors :-)) to do some revisioning of the 
  > primer's text. 
  > >   
  > > One goal of this email was to explain why I was concerned about the 
  > > interoperability statement during the concall as I promised at the 
  > > time to reply in email... 
  > > As far as wsp:ignorable and WS-Policy interoperability were 
  > > concerned, one possible take on it can be that using wsp:ignorable 
  > > might cause at the moment at least WS-Policy-level interoperability 
  > > problems due to third-party consumers using a strict mode. This is 
  > > one interop concern. 
  > 
  > I guess I don't understand why strict mode presents interoperability 
  > challenges. We have both strict and lax mode intersection for a reason. 
  > Those policy consumers that don't want to ignore assertions that are 
  > marked as ignorable can use strict to achieve that objective. Those that 
  > are okay with ignoring what is marked ignorable can use lax mode. The 
  > policy consumer has the choice to do whatever they feel is right for 
  > their circumstances. 
  > 
  > > As far as a provider is concerned, I believe a provider's motivation
  > > to mark the assertion as wsp:ignorable is to try to reach with the 
  > > (assertion) message to as many requesters as possible and yet 
  > > continue to interoperate at the ws-policy level with ideally every 
  > 
  > Agreed. 
  > 
  > > requester out there. Thats's another possible view on what wsp:
  > > ignorable means to the provider as far as a ws-level interop is concerned. 
  > > Then there's on the wire interoperability which is what was referred
  > > to during the call. 
  > 
  > I still don't understand the interop concern. 
  > 
  > >   
  > > Hopefully this explains the reason behind the message I've sent. 
  > >   
  > > I've reviewed the primer and the guidelines yesterday and I've seen 
  > > just a few references to the interoperability term. As far as wsp:
  > > ignorable and interop are concerned, section 2.7 adequately refers 
  > > to both on the wire interop and the ws-policy level interop 
  > > (implicitly by advising to be aware of the impact of this attribute 
  > > on the compatibility of policies). 
  > > I'll add a bug with a proposal to add a minor update to that section
  > > (with respect to referring to interop). Specifically, I'll propose 
  > > to add a text sent by yourself earlier on the ignorability being at 
  > > the discretion of the requester. 
  > >   
  > > Cheers, Sergey 
  > >   
  > >   
  > > ----- Original Message ----- 
  > > From: Christopher B Ferris 
  > > To: Sergey Beryozkin 
  > > Cc: public-ws-policy@w3.org ; public-ws-policy-request@w3.org 
  > > Sent: Tuesday, February 20, 2007 12:52 PM 
  > > Subject: Re: Ignorable assertions and interoperability 
  > > 
  > > 
  > > Sergey, 
  > > 
  > > Would you please log this as a bug against the primer and guidelines
  > > so that it can be tracked? 
  > > 
  > > Also, it would help to have specific areas of the primer and 
  > > guidelines that mention interoperability 
  > > so that we can focus on what exactly needs to be changed. 
  > > 
  > > Finally, if you could provide a proposal to address your concerns, 
  > > that would help greatly towards 
  > > closing the issue. 
  > > 
  > > Cheers, 
  > > 
  > > Christopher Ferris
  > > STSM, Software Group Standards Strategy
  > > email: chrisfer@us.ibm.com
  > > blog: http://www.ibm.com/developerworks/blogs/page/chrisferris
  > > phone: +1 508 377 9295 
  > > 
  > > public-ws-policy-request@w3.org wrote on 02/20/2007 05:52:22 AM:
  > > 
  > > > Hi 
  > > >   
  > > > During the latest concall it was recommended to advise not to use 
  > > > ignorable assertions if the interoperability would be affected...I 
  > > > thought it was a strong statement at a time. 
  > > > The reason for that was that I was assuming at a time a WS-Policy 
  > > > level interoperability was referred to. 
  > > > Most of the time it's obvious what interoperability the spec/primer 
  > > > texts refer to, but I feel it would be useful to revisit (in the 
  > > > primer and guidelines) all references to the 'interoperability' 
  > > > terms and qualify them as appropriate... 
  > > >   
  > > > Cheers, Sergey Beryozkin