Alastiar,
Thanks
very much for this analysis and comment on the patent issue.
With
regard to the "confusion" betwen WS=T/WS-TXM and BTP proponents, I tend to
describe it very differently. Either you resolve the differences among
transaction protocols and models at the endpoints (which BTP proposes to do by
requiring them to all implement a common protocol) or you ask the coordinator to
do the bridging at the "hub" or in this case the distributed hub.
A good
analogy for this debate is the transformation debate, whether it should be done
at the hub, at the endpoints, or both. I would say that the transformation
argument isn't settled (and may never be) because both are important and "it
depends" on what you're doing as to which solution, or combination of solutions
is best. That's what we're essentially saying in WS-CAF, use the solution
that's right for the situation. Don't remove the "it depends" from the equation
since you'll never settle the argument.
With
regard to compensation, I'd refer everyone to the recent discussion at
WS-BPEL. Although I didn't attend and therefore am basing this only on the
presentation, I'd have to say it looks like the problems with a purely
compensation-based approach were highlighted. What order do you process
the compensations? What happens when there's a failure in the
compensation? Do you compensate the compensation? Does this affect
the order? Etc.
Use
the right tool for the right job, let's not say there's only one tool in the
toolbox that's capable of doing anything valuable.
Eric
-----Original Message-----
From: Green, Alastair J.
[mailto:]
Sent: Thursday, December 11,
2003 1:09 PM
To: Mark Little; Newcomer, Eric; Guy Pardon; Greg
Pavlik
Cc: Robin Cover; ;
Subject: RE: [ws-caf] Patent
Issue(s)
Guy,
Thanks for notifying
us all of this patent. I found it a very useful summary of loosely-coupled
transactional issues.
I have to say that I
question the novelty of the claimed “invention”, which seems (at a very hasty
first reading) to boil down to interposition (transaction bridging) plus a
global transaction id.
I believe that the
following publications, products or standards very likely incorporate the key
features of this “invention” and are prior art:
CCR
OSI/TP
OMG
OTS
Transarc Encina
I suspect the Arjuna research project dating back to the late eighties
may also incorporate features of relevance to the claim of invention. Mark
would be better qualifed to comment than
I.
I also believe that
the innards of many transactional products, and the utilization patterns of
databases to achieve high concurrency through application locking which are
employed by thousands of end-users, will also betray many similar key
features.
The cluster of
problems that make application- (service-) level coordination difficult today
for the assemblers of business processes which utilize interacting systems
includes many issues which are just practical (integration with heterogeneous
environments, usability etc). Much of the novelty of
Business Transaction Management (app-level coordination) is
context-conceptual.
One aspect is getting
over the equation of first use with all possible future uses.
For example: How can
a protocol which is associated with ACID possibly possess an interface that is
capable of being used for compensations? Of course, the XA control structure
can be so used. Then, treat XA function names as message names and you have a
distributed “interface” with the same capability … and so on, through all the
permutations of two-phase. XAResource used for JCA
is a useful case.
The second aspect is
failure to abstract sufficiently.
People often confuse
the form or the specific context with the essence. The difficulties that the
proponents of WS-T and WS-TXM have with the notion that all the proposed
interoperable outcome protocols (BTP, WS-T BA, WS-T AT, WS-TXM Acid, LRA and
BP) are in fact versions of one underlying “Ur” protocol (optimizable two-phase outcome with qualifiers), in my view
has its root in this type of failure. (Parenthetically, there is every reason
to have contractual [or contract-referring] information exchanged in contexts
attached to application exchanges: but that need does not transit to the
coordination protocol).
Concretely, the
biggest conceptual problem (and advance) of BTM standardization, is seeing
compensation as one, special case of negative finalization of a high-level
business transaction, coupled with the need to always have a positive finalizer (which in that one, special case will “just” drop its persistent memory of
the business transaction). Put another way: there is a higher-level
abstraction (business transaction), which stands clear above the database
transactions which are now driven by the business
transaction.
Alastair
Green
CTO
Choreology
Ltd
Choreology Cohesions
-- Business Transaction Management software for application
coordination
-----Original
Message-----
From: Mark
Little [mailto:]
Sent: 11 December 2003 03:25
To: Newcomer, Eric; Guy Pardon; Greg
Pavlik
Cc: Robin Cover;
;
Subject: Re: [ws-caf] Patent
Issue(s)
Apologies for any backlog of email
responses, but I've been flying to XML 2003 today. Just to second Greg's email
- LRA is based on Sagas and similar to Open Nested
transactions.
Mark.
----
Mark Little,
Chief
Architect, Transactions,
Arjuna Technologies
Ltd.
www.arjuna.com
----- Original Message -----
From: Newcomer,
Eric
To: Guy Pardon ; Greg
Pavlik
Cc: Mark
Little ; Robin
Cover ; ;
Sent:
Wednesday, December 10, 2003 7:58 PM
Subject: RE:
[ws-caf] Patent Issue(s)
On the
surface, it does not seem to confict since it requires a
specific implementation of Java classes and operations that create the
transaction system, whereas the WS-CAF approach is to wrap or abstract the
transaction systems (i.e. not to create
one).
-----Original
Message-----
From: Guy
Pardon [mailto:]
Sent: Wednesday, December 10, 2003
1:32 PM
To: Greg
Pavlik
Cc: Mark Little;
Robin Cover; Newcomer, Eric; ;
Subject: Re: [ws-caf] Patent
Issue(s)
Hi,
FYI, here is the patent application's description:
http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PG01&s1=pardon.IN.&OS=IN/pardon&RS=IN/pardon
Guy
On woensdag, dec 10, 2003, at 15:07
Europe/Brussels, Greg Pavlik wrote:
Well, the LRA model as
I read it seems to be a relatively close mapping of sagas, which were as
far as I know first described in 1987 by Garcia-Molina. I think it would
be useful if someone took the action to provide a more detailed breakdown
of what exactly is at issue for the group, because it's not obvious to me
after a cursory review of the CheeTah papers.
Guy Pardon wrote:
Hi everyone,
The VLDB paper is
attached. It describes composite systems in the CheeTah prototype (which
served as the provisional application for the US patent).
Concerning WS-CAF, I
think there may be some overlapping with the LRA model described in the
TXM spec.
It was not my intention
to raise panic and 'warn' anybody, rather just to point out that the
patent exists (which is, I believe, required on behalf of TC members).
Best,
Guy
On dinsdag, dec 9,
2003, at 20:27 Europe/Brussels, Mark Little wrote:
Robin, thanks. I think
a description from Guy about how he thinks any patent
relevant to this paper
may conflict with WS-CAF is in order though. Many
companies have been
doing composite applications/transactions for years so
I'd like to know what
aspect of CheeTah may either impact WS-CAF now or in
the future. This is
certainly the first I've heard of CheeTah so from an
Arjuna perspective it
certainly didn't influence WS-CAF, but maybe Guy's
email is intended to
just warn the TC in its future directions?
Mark.
----- Original Message
-----
From: "Robin
Cover" <>
To: "Newcomer,
Eric" <>
Cc: "Guy
Pardon" <>; <>
Sent: Tuesday, December
09, 2003 7:08 PM
Subject: RE: [ws-caf]
Patent Issue(s)
Perhaps:
CheeTah: a Lightweight
Transaction Server for
Plug-and-Play Internet
Data Management
-------------------------------------------
Guy Pardon, Gustavo
Alonso.
-------------------------------------------
Abstract:
The ability to maintain
transactional interaction
in a distributed system
has proven to be a key feature
in information systems.
Unfortunately, as technology moves
towards more
distribution and decentralization, it becomes
increasingly difficult
to use existing transactional
tools. In fact, current
solutions are entirely unsuitable
for what we call
composite systems. Composite systems
can be characterized as
a collection of distributed,
autonomous components,
linked in an arbitrary configuration.
In this paper, we
describe CheeTah, a Java based set of
tools for building
composite components capable of
interacting
transactionally in arbitrary, dynamically
changing
configurations. We describe the technology provided,
how designers would use
it to build composite transactional
systems, and examine in
detail the performance of the
resulting solution.
Among the results we have achieved,
the performance and the
simplicity of use are of particular
interest.
http://www.inf.ethz.ch/department/IS/iks/publications/pa2000.html
http://www.inf.ethz.ch/department/IS/iks/publications/files/pa2000.pdf
-----------------------------------------------------
Robin Cover
XML Cover Pages
WWW:
http://xml.coverpages.org
Newsletter: http://xml.coverpages.org/newsletter.html
On Tue, 9 Dec 2003,
Newcomer, Eric wrote:
Guy,
To second Mark's email,
can you please also send additional information
about the patent, such
as the VLDB paper you mention.
Thanks,
Eric
-----Original
Message-----
From: Guy Pardon
[mailto:]
Sent: Tuesday, December
09, 2003 9:53 AM
To:
Subject: [ws-caf]
Patent Issue(s)
Hi all,
As a TC member it is my
duty to report that there exists a US patent (US
patent application
09/682,969 -- finally approved about two months ago)
concerning composite
systems and an additional European application being in
process. This patent is
probably relevant to the CAF specs (and most likely
to BTP as well).
Basically, the patent
is an extension of the Composite Systems VLDB
paper we (Gustavo
Alonso and I) had at VLDB2000.
Best,
Guy
Dr. Guy Pardon
( )
Atomikos: Your Partner
for Reliable eBusiness Coordination
http://www.atomikos.com/
The information in this
email is confidential and only meant for the
addressee(s). The
content of this email is informal and will not be legally
binding for Atomikos.
Dr. Guy Pardon
( )
Atomikos: Your Partner
for Reliable eBusiness Coordination
http://www.atomikos.com/
The information in this
email is confidential and only meant for the addressee(s). The content of
this email is informal and will not be legally binding for Atomikos.
Dr. Guy Pardon (
)
Atomikos: Your
Partner for Reliable eBusiness Coordination
http://www.atomikos.com/
The information in
this email is confidential and only meant for the addressee(s). The
content of this email is informal and will not be legally binding for
Atomikos.
