RE: Yet more issues to resolve

[Martin W Sachs <mwsachs@us.ibm.com>]

David,

The definition of persistDuration in your email looks OK.

My point about decoupling persistence from reliable messaging was a CPA/CPP
point, not a MSH point.  I am simply suggesting that two parties might have
reasons to come to agreement on persistence that have nothing to do with
the MSH in addition to its use with RM.

Regarding "I also don't like the idea of placing a restriction on the MSH
to persist a message until the transaction is complete, ..."  I don't like
placing that restriction either.  I was asking for the opposite - that the
MSH specification should not say anything which either prescribes or
suggests that a message can be deleted from the persistent store as soon as
it reliably reaches the destination MSH.  Earlier versions of the RM
specification included such words.

Regards,
Marty
*************************************************************************************

Martin W. Sachs
IBM T. J. Watson Research Center
P. O. B. 704
Yorktown Hts, NY 10598
914-784-7287;  IBM tie line 863-7287
Notes address:  Martin W Sachs/Watson/IBM
Internet address:  mwsachs @ us.ibm.com
*************************************************************************************



"Burdett, David" <david.burdett@commerceone.com> on 12/27/2000 11:20:24 AM

To:   Martin W Sachs/Watson/IBM@IBMUS
cc:   ebxml-transport@lists.ebxml.org, ebxml-tp@lists.ebxml.org
Subject:  RE: Yet more issues to resolve



Marty

In version 0.9a of the spec, a parameter called "pesistDuration" is defined
that is described as follows:

"PersistDuration is the minimum length of time in days that a Message that
is sent reliably is kept in Persistent Storage by a MSH. The value used for
PersistDuration is an implementation decision although it MUST be greater
than the value of the TimeToLive parameter for any message that is sent.

If a duplicate message (i.e. with the same MessageId) is received before
the
PersistDuration has passed, then the MSH that receives it MUST process it
as
a duplicate message as described in sections 10.2.1.1 and 10.2.1.2.

If a duplicate message is received after the PersistDuration has passed,
then although it may be treated as a duplicate, the sender must realize
that
it will probably be treated by the MSH as if the message were a new message
that had not been received before."

So as it stands, the persistDuration only applies to Relilable Messaging
behavior which I think is right. I know that there are other, e.g. legal,
reasons why a messages might be persisted beyond this time. However from a
MSH perspective, I think we can only specify the behavior of the MSH and
nothing else.

I also don't like the idea of placing a restriction on the MSH to persist a
message until the transaction is complete, since the MSH will probably need
to be told by the application that the transaction is complete and it's
possible that some backend systems will not be able to easily do this.

Do you think the existing definition is OK?

David

-----Original Message-----
From: Martin W Sachs [mailto:mwsachs@us.ibm.com]
Sent: Tuesday, December 19, 2000 9:56 AM
To: Christopher Ferris
Cc: ebxml-transport@lists.ebxml.org; ebxml-tp@lists.ebxml.org
Subject: Re: Yet more issues to resolve



Chris,

Regarding issue 19:  I agree that there should be nothing in the TRP spec
about how long a message must be persisted since higher layers are
involved.  Perhaps the messaging spec should say that persistence must be
at least until the reliable messaging procedure has been completed for that
message transmission.  I suggest a non-normative note explaining the
issues.

In my opinion, at the higher levels, persistence should be at least until
the business transaction is concluded.  Persistence beyond that is probably
not a matter that has to be agreed to.  It is probably an internal matter
for each party.

If the persistence element will be in your upcoming CPP/CPA DTD, please
supply some explanatory text with it.  I suggest not coupling the
persistence element in the CPA to reliable messaging.  While it is
essential to reliable messaging, it is also something that might be needed
without ebXML Reliable Messaging.  For example, if the parties use a
transport that is reliable in and of itself, they would probably not want
to invoke ebXML Reliable Messaging on top of it but they might want to
specify something about persistence.

Regards,
Marty





****************************************************************************

*********

Martin W. Sachs
IBM T. J. Watson Research Center
P. O. B. 704
Yorktown Hts, NY 10598
914-784-7287;  IBM tie line 863-7287
Notes address:  Martin W Sachs/Watson/IBM
Internet address:  mwsachs @ us.ibm.com
****************************************************************************

*********



Christopher Ferris <chris.ferris@east.sun.com>@east.sun.com on 12/19/2000
12:23:17 PM

Sent by:  Chris.Ferris@east.sun.com


To:   ebxml-transport@lists.ebxml.org
cc:
Subject:  Re: Yet more issues to resolve



Ian,

Thanks for sending these out. Some comments below.

Cheers,

Chris
ian.c.jones@bt.com wrote:
>
> TR&P people,
>
>         Sorry this is late - the real world gets in the way occasionally.
>
> The following issues may now have been overtaken by events but we need to
at
> least acknowledge this so that I can get the database of issue and
changes
> update by the New Year.
>
> ####
> Issue 15
> Title - RM Info
> Detail - 7.9.4  - RM Info: why isn't this in routing header?
>
> Proposal -  Move to Routing Header
> Resolution -
> Response By - December 21

I have to disagree with this. The ReliableMessagingInfo
element applies to the message, not to a particular hop
along the way. Note that David has crafted a revised section
on RM in the draft we've been collaborating on which we
hope to get to the list today (although, we recognise that
it still needs work).

>
> ####
> Issue 16
> Title - TPAInfo
> Detail - Add new section containing all TPA(CPA) information
>
> Proposal - see above
> Resolution -
> Response By -

This one I'm not sure I understand. I thought that we agreed
in Tokyo to flatten the TPAInfo section by moving all of
the child elements to be direct decendants of Header.

What information was missing from TPAInfo anyway? I'm not
clear on what the proposal really suggests.

>
> ####
> Issue 17
> Title - Sequence number
> Detail - 7.10 SequenceNumber as defined adds little or no value over the
> MessageID element required in MessageData.  Recommend removing this
section
> and the corresponding references to SequenceNumber in later  examples,
the
> DTD and the schema.
> If this section remains, must define the exact content of the
SequenceNumber
> element when the numeric value is greater than 999.  Is the next value
> "1000" or "1,000"?  Is the text for the maximum value  "999999999" or
> "999,999,999" or are both allowed (and equivalent)?  Side note: Numeric
> formats vary by locale and a comma is not always the thousands
> If this section remains, "long time" should be defined.  At least, refer
to
> a TPA which makes this concrete for a specific trading relationship or
> mention later text on this subject (if any).
>
> Proposal -
> Resolution -
> Response By -

Since we're going to spec the schema using XMLSchema, we can
be more precise in the typing of elements and attributes.
I agree that the spec needs to be tightened up for this
particular element.

I'll have to review David's revision of RM to see what that
has to offer.

>
> ####
> Issue 18
> Title - URI definitions in RM
> Detail - 7.10 - SenderURI, ReceiverURI and ErrorURI are not defined.  Are
> they identifiers or service locations?  From later discussion in this
> document, it appears that ErrorURI is a service location at which error
> responses may be received.  The other two aren't discussed much.
However,
> I'd recommend they be defined similarly to the PartyId elements in the
> Header (i.e. the parties participating in the current leg of the
journey).
> That requires adding a context attribute to SenderURI and ReceiverURI and
> (potentially) renaming the elements.  Alternatively, SenderURI and
> ReceiverURI may somehow identify the service location used in this
> particular leg (this is probably redundant information for ReceiverURI
with
> the transport destination and SenderURI may not exist -- not all senders
are
> reachable in return).
>
> Proposal -
> Resolution -
> Response By -

I assume that the subject refers to URI elements in RoutingHeader
not RM. Agree that these need to be more precisely defined.
As to defining them similarly to the PartyId element...
I had actually proposed to David in our discussions that
instead of defining different elements, that we re-use
To and From but with precise wording that the PartyId
MUST be an URL form of URI (e.g. something addressable).

This also brings to mind a security issue (possibly) as
if an intermediate signs a header (with the added RoutingHeader
element) then it MAY be important to be able to identify
the intermediary with the specific RoutingHeader. I hadn't
thought of this before, but it MAY be important to consider.

>
> ####
> Issue 19
> Title - Persistent storage
> Detail - 7.11 - "Persistent storage" actually lasts how long?  Is the
> original message deleted by the Messaging Service immediately after
> receiving an acknowledgement?  In the case of an error, which is reported
to
> the sending application (party), does that report also result in deletion
of
> the original message from the persistent storage?
> What information does the Receiver store persistently in this step?
> Recommend storing the MessageID of the original message and the entire
> response document.  To check for "exactly the same as the original
message"
> as described on line 828, may be necessary to store entire original
message
> or its checksum as well.
>
> Proposal - This is out of scope of the TR&P if required it should be in
the
> CPP/CPA
> Resolution -
> Response By -

David has added a section on persistence in his RM draft
proposal. It doesn't get into "how long" as this is correctly
identified as being something that the parties MUST agree
upon and have reflected in the CPA. A new element is being added
to the CPA for this purpose (e.g. to capture the persistenceDuration
with which a message is to be archived).

>
> Ian Jones
> E-Commerce Engineer
>
>