Doug, is that
scenario required for RM or polling in general? As soon as you start talking
about a server side RMS establishing a sequence to an un-addressable client I
think you are beyond RM. You can’t establish inbound communications from
a server to an un-addressable client without RM so why is this an RM problem?
If we are looking to
add a tightly scoped polling mechanism to RM for specific scenarios this one
would not be high on my list.
From: Doug Davis
[mailto:dug@us.ibm.com]
Sent: Friday, April 28, 2006 1:05
AM
To: ws-rx@lists.oasis-open.org
Subject: Re: [ws-rx] i089 proposal
I do believe that the scenario you're talking about is a required
one but I would phrase it
a bit
differently. An RMS (whether its the client-side RMS or the server-side
RMS) needs
to be
able to follow the same RM processing model. And part of the processing
model
is the
ability to decide "if", "when" and "how" to use RM.
As we talk about in the Q&A
section
of our proposal, an RMS having the option of choosing to decide which RM
sequence
to
use, when to create new ones, or even when to use RM at all are all part of the
RM
processing
model and those aspects need to be maintained even in these anon cases.
In your proposal you put the burden on the RMD to make a lot decisions on
behalf of
the
RMS, that's quite a change to the RM processing model and I have no idea how
the
RMD
could ever know all it would need to know to make those decisions. For
example, how
would
it know when a new sequence is needed by the RMS? That is why I believe
our
proposal
is a better fit for RM - it allows the RMS to retain all of the same logic and
choices
that
it has in the async world. Our proposal simply re-establishes the
backchannel that
the
RMS (on the server side) is looking for - nothing more. Once that is
there, it is then
back
to "standard operating procedures" - the RMS can do whatever it would
normally
do.
thanks,
-Doug
Paul Fremantle <paul@wso2.com>
04/27/2006
05:51 PM
|
To
|
Marc Goodner <mgoodner@microsoft.com>
|
cc
|
wsrx <ws-rx@lists.oasis-open.org>
|
Subject
|
Re: [ws-rx] i089 proposal
|
|
If
the TC isn't attached to this scenario then this section can be
deleted. The scenario is simply when you want to
send unreliably but
receive reliable responses. I've heard this stated
as a requirement in
some scenarios, but WSO2 doesn't have any pressing
scenarios of this ilk
so we would be happy either way.
Paul
Marc Goodner wrote:
> So is an RMS engaged at the client side or
not? This is weird, why would
> the infrastructure on the client side decide to
do this?
>
> Marc Goodner
> Technical Diplomat
> Microsoft Corporation
> Tel: (425) 703-1903
> Blog: http://spaces.msn.com/mrgoodner/
>
>
> -----Original Message-----
> From: Paul Fremantle [mailto:paul@wso2.com]
> Sent: Thursday, April 27, 2006 12:57 PM
> To: Marc Goodner
> Cc: wsrx
> Subject: Re: [ws-rx] i089 proposal
>
> Marc
>
> This is the case where the client is making
an offer but not creating an
>
> outbound sequence - thats all. A client
offers a sequence, and then
> reliably gets messages from the server that
are buffered under that
> sequenceID.
>
> Paul
>
> Marc Goodner wrote:
>
>> I still don't understand why offered
sequence is being used in the
>> explanation. If this is going to usually
be used with an offered
>> sequence I'd like to understand how, that
isn't explained in my mind.
>>
> If
>
>> it is applicable for any sequence,
offered or not, I'd like to
>> understand that as well. The current text
only confuses me in its use
>>
> of
>
>> the term and I'm afraid your explanation
below isn't helping me get
>>
> past
>
>> it. Perhaps comparing the two modes would
be a better approach.
>>
>> On 4.2, "Offer a sequence without
the overhead of requesting one"? I
>> don't understand. The text refers to the
RMD requesting a sequence
>>
> from
>
>> the RMS, but it sounds like this is an
unreliable request so doesn't
>> that mean there is no RMS at the client?
Isn't this about the service
>> acting as an RMS and the client acting as
an RMD? So the pattern would
>> be client sends one way message to
service (GetMessage?), response is
>> Offer, then client sends a response to
the response of Accept? What
>>
> does
>
>> the service return to that? Why wouldn't
the service send a CS in the
>> body of the GetMessage response to the
client?
>>
>> Marc Goodner
>> Technical Diplomat
>> Microsoft Corporation
>> Tel: (425) 703-1903
>> Blog: http://spaces.msn.com/mrgoodner/
>>
>>
>> -----Original Message-----
>> From: Paul Fremantle
[mailto:paul@wso2.com]
>> Sent: Monday, April 24, 2006 1:11 AM
>> To: Marc Goodner
>> Cc: wsrx
>> Subject: Re: [ws-rx] i089 proposal
>>
>> Marc
>>
>> I use the words "Offered
Sequence" informatively and non-normatively.
>> This is most likely to be used with an
offered sequence, but isn't
>>
> tied
>
>> to that.
>>
>> As regards 4.2, this is there to satisfy
the scenario where you only
>> want reliable responses. I added this in
for discussion because I know
>>
>
>
>> that some members find this an important
scenario. In that case you
>>
> need
>
>> to be able to Offer a sequence without
the overhead of requesting one.
>>
>
>
>> It is related to the anonymous client
because without a real endpoint
>> the server cannot send a CS to the client
so it relies on an offer.
>>
>> Paul
>>
>> Marc Goodner wrote:
>>
>>
>>> Given 1 and 2, yes some text that
clarified that not only is this
>>> specific to RM but that a general solution
would be preferable would
>>>
>>>
>> be
>>
>>
>>> best.
>>>
>>> On 3 I suppose, I don't like seeing
WS-A headers in the body of a
>>> message though. Do you really even
need the response for a specific
>>> message? Why not return any responses
or messages for that sequence
>>>
>>>
>> that
>>
>>
>>> have not been acknowledged? And what
are you talking about when you
>>>
>>>
>> say
>>
>>
>>> this is tied to the offered sequence?
What offered sequence? I don't
>>>
>>>
>> see
>>
>>
>>> anything here that ties the use of
your GetMessage proposal to an
>>> offered sequence.
>>>
>>> I don't understand section 4.2 in
your proposal at all. What does
>>>
> this
>
>>> have to do with the rest of this
proposal?
>>>
>>> Marc Goodner
>>> Technical Diplomat
>>> Microsoft Corporation
>>> Tel: (425) 703-1903
>>> Blog:
http://spaces.msn.com/mrgoodner/
>>>
>>>
>>> -----Original Message-----
>>> From: Paul Fremantle [mailto:paul@wso2.com]
>>> Sent: Thursday, April 20, 2006 1:57
AM
>>> To: Marc Goodner
>>> Cc: wsrx
>>> Subject: Re: [ws-rx] i089 proposal
>>>
>>> Marc
>>>
>>> 1) Yes - I completely aimed this to
be a specific model for RM. I
>>>
>>>
>> would
>>
>>
>>> be happy to include language that
indicates that if a more general
>>> purpose firewall crossing mechanism
was in place this should not be
>>> used.
>>> 2) The wsrm:Identifier is a required
part of my proposal, and
>>>
>>>
>> therefore
>>
>>
>>> this proposal is completely tied to
the use of RM.
>>> 3) The suggestion of using
messageNumber is interesting. The
>>>
>>>
>> motivation
>>
>>
>>> for using a message ID was that there
may be situations where I
>>>
> really
>
>>>
>>>
>>
>>
>>> want the response to a given message.
We do not - so far - have any
>>> concept of a response to a given RM
messageID, so that seemed like a
>>>
>>>
>> new
>>
>>
>>> concept to me, whereas WS-A systems
do keep track of responses to
>>>
>>>
>> given
>>
>>
>>> messageIDs. But I'm not averse to
your suggestion. However I wish to
>>> make clear that in my proposal you MUST
have both the Identifier and
>>>
>>>
>> the
>>
>>
>>> messageID - so it is still very
closely tied to the offered sequence.
>>>
>>> Paul
>>>
>>> Marc Goodner wrote:
>>>
>>>
>>>
>>>> I hope that this is scoped to RM
and not a general purpose polling
>>>> mechanism. I assume that is your
intent in that you use the
>>>> wsrm:Identifier and indicate that
you see this being part of the
>>>>
> core
>
>>>> spec. Still it seems like
including language that indicates that
>>>>
>>>>
>> would
>>
>>
>>>> be advised, particularly noting
that if there were a general purpose
>>>> polling mechanism that it might
be preferred over this one.
>>>>
>>>> So following from that why is
MessageID in the GetMessage? Isn't the
>>>> identifier enough? If it isn't
wouldn't the addition of
>>>> wsrm:MessageNumber do the trick?
>>>>
>>>> Marc Goodner
>>>> Technical Diplomat
>>>> Microsoft Corporation
>>>> Tel: (425) 703-1903
>>>> Blog:
http://spaces.msn.com/mrgoodner/
>>>>
>>>>
>>>> -----Original Message-----
>>>> From: Paul Fremantle
[mailto:paul@wso2.com]
>>>> Sent: Thursday, April 06, 2006
12:40 PM
>>>> To: wsrx
>>>> Subject: [ws-rx] i089 proposal
>>>>
>>>> Folks
>>>>
>>>> At the F2F I took away an action to
come up with a proposal for i089
>>>>
>
>
>>>> before the call. I'm sorry its so
close to the call.
>>>>
>>>> I've attached a proposal for
review. This is a work in progress, but
>>>>
>>>>
>> I
>>
>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>> think it helps call out some of
the issues involved around i089.
>>>>
>>>> I think the most important
questions for the TC are:
>>>>
>>>> (1) How does a customer/user use
WSRM in a two-way scenario if one
>>>>
>>>>
>>>>
>>> side
>>>
>>>
>>>
>>>> is anonymous?
>>>> (2) Adding a
"GetMessage" makes the protocol more symmetric, but
>>>>
> also
>
>>>>
>>>>
>>
>>
>>>> might overlap with a wider
non-reliable solution to this problem. Is
>>>>
>>>>
>>>>
>>> it
>>>
>>>
>>>
>>>> in the scope of this TC to add
this?
>>>> (3) In the case we do add it,
what criteria do we use to select
>>>>
> which
>
>>>>
>>>>
>>
>>
>>>> message to request.
>>>> (4) Is this a generic solution
(i.e. can the RMD request messages
>>>>
>>>>
>> from
>>
>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>> the RMS in all cases) or special
cased to anonURI scenarios?
>>>>
>>>> Paul
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>
>>
>
>
--
Paul Fremantle
VP/Technology, WSO2 and OASIS WS-RX TC Co-chair
http://feeds.feedburner.com/bloglines/pzf
paul@wso2.com
"Oxygenating the Web Service Platform",
www.wso2.com