Day 1 - 13th March

 8:30 -  9:00                 Breakfast

 9:00 - 10:30                Welcomeand introductions

 10:30 - 10:50              Break

 10:50 - 12:30              Positionpapers and presentations

WG Members to present positionpapers/ideas for the group. Time to be divided equally.

 10:50 - 11:20              LucianWischik, Bolgna University - invited talk

ProcessCalculii for Web Services (30 mins)

 11:20 - 11:40              KevinLiu, SAP,

Position paper(20 mins)

 11:40 - 12:00              DanielAustin, Grainger,

Towards webservices choreography (20 mins)

 12:00 - 12:10              YokoSeki, Hitachi,

Position paper(10 mins)

            12:10- 12:20                CarolMcDonald, Sun,

Position paper(10 mins)           

 12:30 -  1:30               Lunch

 1:30 -  3:00                 Position papers and presentations (cont)

1:30 - 1:50                   DuncanJohnston-watt, Enigmatec Corporation,

Making webservices work. (20 mins)

            1:50- 2:20                    TonyFletcher/Peter Furniss, Choreology,

Choreographyand Coordination (30 mins)

            2:20- 2:35                    AssafArkin, Intalio,

Modelingcausality in WS communication (15 mins)       

            2:35- 2:50                    JimHandler, Univ of Maryland,

Dynamic WebService Composition using Semantic Markup (15 mins).

2:50 Ð 3:10                   FrankMcCabe, Fujitsu

Frank'sposition as opposed to Fujitsu's with a WSA bias (15 mins)

 3:10 -  3:30                 Break           

            3:30Ð 3:50                    GregMeredith, Microsoft,

Orchestrationor Contracts É (20 mins)

 3:50 -  5:00                 Invitedtalks and Challenges/Issues from the Chairs

            3:50- 4:30                    Jean-Jacques Dubray

            4:30- 5:00                    Issuesfrom the Chairs & discussions

 5:00 -  5:15                 Wrapup for day 1

 6:30                            Selfpay dinner at local restaurant

Day 2 - 14 March

 8:30 -  9:00                 Breakfast

 9:00 - 10:30                WGLogistics

Weekly callschedule


Group etiquette

 10:30 - 10:50              Break

 10:50 - 12:30              Requirementsgathering session

Break outs.Suggestion include, but not limited to, use cases and formalism underpinning.Actual break outs to be decided at the meeting.

 12:30 -  1:30               Lunch

 1:30 -  3:00                 Requirementsgathering session (cont)

Includingsummaries of break outs

 3:20 -  5:00                 Roadmap,schedule and wrap up.



Yaron Goland

BEA Systems

Anthony Fletcher

Choreology Ltd

Peter Furniss

Choreology Ltd

Mayilraj Krishnan

Cisco Systems Inc

Ricky Ho

Cisco Systems Inc

Paul Lipton

Computer Associates

Fred Cummins


Steve Ross-Talbot

Enigmatec Corporation (co-chair)

Duncan Johnston-Watt

Enigmatec Corporation

Francis McCabe

Fujitsu Ltd

William Vambenepe


Yoko Seki

Hitachi, Ltd.

Assaf Arkin

Intalio Inc.

Sanjay Patil


Allen Brown

Microsoft Corporation

Greg Meredith

Microsoft Corporation

Eunju Kim

National Computerization Agency

Greg Ritzinger


Martin Chapman

Oracle Corporation (co-chair)

Jeff Mischkinsky

Oracle Corporation

Nickolas Kavantzas

Oracle Corporation

David Chapell

Progress Software

Kevin Liu


Steven White

SeeBeyond Technology Corporation

Carol McDonald

Sun Microsystems, Inc.

Jon Dart

TIBCO Software

William Eidson

TIBCO Software

Andre Huertas

Uniform Code Council

Melanie Kudela

Uniform Code Council

Jim Hendler

University of Maryland (Mind Lab)

Daniel Austin

W. W. Grainger, Inc.

Leonard Greski

W. W. Grainger, Inc.

Hugo Haas

W3C (W3C staff contact)

Yves Lafon

W3C (W3C staff contact)

Ed Peters

webMethods, Inc.

Prasad Yendluri

webMethods, Inc.

Summary of Actions:


ACTION:Hugo Hass: will post archive URL algorothm to IRC



ACTION:W3C staff to setup teleconf [1]

ACTION:Hugo to send choreography definitions to the list [2]

ACTION:write up use cases [3]

Summary of openissues/questions:

Weneed an internal glossary of terms.

Whatdo we mean by external process choreography?

Whatdo we mean by internal process choreography?

Whatdo users actually need?

Thisgroup is all about capturing external behaviour of choreography?

Thisgroup is all about internal process choreography?

Thisgroup is all about capturing internal and external behaviour of processchoreography?


Welcome andIntroductions

MC:           Leadsintroductions

              Eachmember introduces themselves) (roughly 25 present)

              Scribesto be assinged in half day chunks

              Scribeslist to be established; rotation of scribes in order to reduce

wear and tear

              Explanationof W3C process

              HugoHaas and Yves Lafon are staff contacts

              Reviewof various uri's (included):

              Alltech work is public

              Alldocuments are posted, as well as the mailing lists

              thishas its good and bad points. WG may receive comments from outside


              Membersmay join at any time during the two year duration

              Areading list for the WG will be established (see some uri's enclosed)

              Allmailing lists are archived

              Providespublic record of group activities


                     Don'tsend large files directly the to WG mailing list

                     Insteadsend them to the archive list,

                     Thensend the URL to the list (email by reference)

                     Don'tpost trade secrets!

                     HTMLformats preferred and readable format (i.e. text) is okay.

                     Otherformats are okay but with HTML too.

ACTION: Hugo Haas:will post archive URL algorothm to IRC


       WG list:

                     F2Fwill be announced 8 weeks prior;

                     Teleconfagendas 24 hours prior

Note:         SRTleaves the room

              WGmembers to read group charter ( will ocver this PM)

              Alsoplease review the WSCI spec, it is a key input for this WG

              W3Chas introduced bugzilla for issues tracking; will use on this WG


Note:         SRTreturns to the room

SRT:          Askslate arrivals to introduces themselves

P:            Prasadfrom webMethods

GM/AB:        Gregmeredith and Alan Brown from Microsoft

LucianWischik, Bolgna University - invited talk

       ProcessCalculii for Web Services (30 mins)

FMC:          Whenyou say possible state, do you mean one involving an external message?

LW:           yes

DA:           Arethese sequences symmetric?

LW:           Generally.If the implementation has different sequences, they can be


GM:           There'sanother aspect of bisimulation, concerned with complexity.

GM:           Canyou speak to the issue of the complexity of checking the sequences

GM:           isthis (polynomialy) decidable?

LW:           No,I can't say anything

GM:           Mentionsother researchers in this area

GM:           usefulto understand, bisimulation is simplest for checking

GM:           thereason things go bad in laguage equivalence is that you have to search

GM:           withbisimulation it's easier

                     seeGM's presentation under references.

JD:           Arethere methods of specifying choreography that make decidability

testing easier?

DuncanJW:     GM referenced Colin Stirlingand Hans Huttel here are the uri's

                  - Colin Stirling

JD:           Isthere an easier means than the diagrams in your presentation (to LW)

LW:           No,not really

LW:           whatyou are saying is, is there a more restricted language that makes


LW:           yesthere are, we need to find an intermediate solution that makes things


SRT:          Therewas work done by others that uses the mu-calculus

SRT:          areyou familiar with this?

LW:           No

LW:           Thisis quite exciting to the academia, we've had the pi-calculus for

years, with no killer app

LW:           perhapsWS is a good use

LW:           willrely on mailing list, as won't be able to be present

EP:           Twopart Q: in order to make the bisim testing easier, are there other

ways to reduce complexity?

EP:           canyou elaborate on your bisim example? I'm not clear on the


EP:           perhapswe can get away w/o this functionality

LW:           passeson 1st Q, addresses 2nd: do we really need reconfigurability?

LW:           seeslide 10

LW:           Icannot think of a WS example, but this is an issue in academe

EP:           dothese languages form a continuum? Is there one that makes the testing


LW:           itseems like it would be worthwhile to find the simplest solution for WS

SRT:          thereis a classic example in pi-calculus concerning cell phones

SRT:          sayyou want to understand roaming

JD:           Ithink the first example in the presentation is message-driven switching

SRT:          suggestslooking at papers on LW's web site

SRT:          usefulto have some background from LW

SRT:          wecan debate the proper formalism

       Kevin Liu(SAP)

       PositonPaper (20 mins)

KL:           chorneeded for large scale implementations

KL:           focuson convergence

KL:           muchwork already done, WG should use prior art

KL:           seeksvendor neutral solution

KL:           possiblemodularized approach if problem domain too large for a single spec

KL:           industryawaits solution

KL:           reliability,security, processing model out of scope

JD:           youmentioned implementation is out of scope, can you elaborate?

KL:           wesee an interface for interaction

KL:           howiits implemented should be left to the user

       DanielAustin (W.W. Grainer)

       Towards webservices choreography (20 mins)

DA:           Wedo a lot of e-commerce

DA:           Interms of choreography, we are interested in how to integrate a lot of


DA:           comingfrom a user POV

DA:           forthis presentation, we thought about the problems that we would like to

see the WG provide solutions for

DA:           4problems: sticky policies, WS processing model, orchestration, interop

DA:           weneed a framework

DA:           slide3: Sticy Policies

DA:           howto handle metadata?

DA:           isan outside controller necessary to manage the chain of composite


DA:           slide4: Processing Model

DA:           slide5: Orchestration

DA:           Needto define orchestration vs. choreography, relationship with business


DA:           whatis the practical limit on nodes in call chain? look at the real world

DA:           slide6: Interoperability

DA:           lookingat the organizational level

DA:           semanticsissues

LG:           thesemantics issue is critical, and across organization nature of this

work is going to be hard

DA:           slide7: Summary

DA:           implementationof a solution can be very costly (e.g. BPMI)

DA:           wewant a practical solution

AH:           UN/CEFACThas done some work on the semantics side

DJW:          wecan present/relay user's POV (answer to DA's question about users)

KL:           wethink that the implementation aspect of the processing model is out of


DA:           weare interested in addressing the concept of a shared context between

composite services

SRT:          Weare hearing people about addressing common understanding; how many

people are experimenting with Semantic Web technologies?

Crowd:               not thatmany

SRT:          JimHendler will talk about this later on

       Yoko Seki,Hitachi,

       Positionpaper (10 mins)

YS:           slide1: Background

YS:           talksabout workflow

SRT:          whatwas that about grid computing?

YS:           developersmay use WS to control flows in the grid

KL:           whenyou says WS_Choreography what do you mean?

YS:           theresults of this WG

       CarolMcDonald, Sun,

       Positionpaper (10 mins)

FM:           youmentioned mgmt, do you see mgmt as a choreography issue?

CM:           thinksthat is it is useful

JD:           weshould use some of the EBXML work...can you elaborate on your BPSS


CM:           basisof contractual agreement

JD:           howis the partner concept in BPEL, how does that relate?

CM:           whatdo you mean by long-running dynamic services?

CM:           typicalin business processes

GM:           wrtscope, do we feel that org level computing is the only one in our


GM:           canwe imagine apps that use BPs, is this in scope?

MC:           myopinion is yes

MC:           nothingin our work says anything about organizational boundaries

M:            hasWSA considered these issues?

MC:           yes,but from a diff point of view

SRT:          ifXML processing can be made more efficient, choreography will play a

greater role

SRT:          sayin 2 years time...we need to future-proof our work in this light

GM:           futurePDAs are today's high powered workstations

PF:           thereis no CORBA 'choreography" because we have now reached the point

where it's needed

??:           themagnitude of users forces the use of online svcs, rather than personal


PF:           absolutely

       DuncanJohnston-watt, Enigmatec Corporation,

       Making webservices work. (20 mins)

SRT:          thereis a paper on naming that is applicable

              urito book or paper to be supplied as part of reading list

SRT:          Finalcomment, we do need to address the formal semantics of WS-chor

SRT:          Isanyone working with investment banks?

JD:           Reuterssupplies financial data to these banks

SRT:          areyou seeing adoption of WS?

SRT:          it'simportant to know there are potential users that might actually pay

attention to us


       PeterFurniss, Choreology,

       Choreographyand Coordination (30 mins)

pf:           choreologymeans "science and notation of movement"

pf:           choreologyltd "interplays of commerce"

pf:           coordination- agreement of multiple parties on mutually shared state

(more than 1-1)

pf:           agreementrequires "contingent" offers

pf:           goalof this is "assured common knowledge"

pf:           theinteraction between the participants thus needs to be conditionalizaed

pf:           needboth and interaction description and a process description

pf:           needcoordination in either case

pf:           discussionof cancellation of processes during service "failures"

pf:           goodbusiness protocols need coordination

pf:           discusses"thought experiment" of taking BTP as an app protocol

pf:           suggestwe use BTP and WS-C/T as transition protocol?

Crowd:       discussionof whether group is looking at transaction protocols or not

Crowd:        discussionof possibility of group doing a set of "small specs"

ygoland:      we need to get to fitthings to existing protocols

jimh-scribe: maybe we should make it so our product has"hooks" for other protocols,

there are many

       AssafArkin, Intalio,

       Modelingcausality in WS communication (15 mins)

AA:           Ihave investigated about modelling all sorts of processes

AA:           manyof the things we have been looking at talk about "causality"

AA:           from"intalio: The business process mgt company" (end quote)

AA:           synchronizationis essentially a causal relation between eventws

AA:           choreographyshould be based around "long running interactions"

AA:           wecan define how things could "possibly happen"

AA:           wewant to be able to do simulation or analysis before we start

AA:           modularity,composition very important

AA:           restrictionon bi-lateral choreography is artificial and can't work

AA:           showssome requirements on choreography (too fast to scribe)

AA:           discussesreqs for a formal model - run simulation, make predictions,

              expressthings as a "formula"

AA:           thatis, be able to say something like "how long to receive a quote from N


AA:           needsimple, elegant, and minimalist formal model

AA:           butneed to allow mappings between formal models

AA:           suggesteswe use pi-calculus

AA:           webis "mobility, replication and passing processes as data"

AA:           wantit defined to be reduced to the formal model

AA:           norestriction on number of service types of services

AA:           multipleforms of composition

AA:           describesthe language he has described - simple at base, complexity in

putting it together

AA:           useWSDL for interaction betw loosely coupled services

AA:           providesvarious parallel flows

AA:           specis only 100 pages or so...

AA:           Ipopose a model for the language, WSCI as proof of concept

Crowd:        discussionof relation between this and CSP (?)

AA:           solvesour customer's problems

ygoland:      want to make sure grouprealizes one big choice is "either inside-out or


ygoland:      langauge or langaugeplus things around it

Crowd:        discussionof discussing that stuff later.

       JimHendler, Univ of Maryland,

       Dynamic WebService Composition using Semantic Markup (15 mins).

[1] note:this is not a permanent

URI,the approach via clicking above will take you to the permanent page when thisis finalized)



JH:           whycan't different apps talk to each other - have to rekey into pda what

its displaying

JH:           group(Univ Maryland) - also working on linking devices (projector, pda

              etc)by choreographies

JH:           wantto be able to analyse what the web agents are doing - e.g. ask of

description if

JH:           giventhe information the service can get to the desired solution.

JH:           c.f.going through 15 forms before finding can't fill in the last one

JH:           DAML-S(darpa agent markup language) led to Web Ontology WG (co-chair Jim H)

JH:           weakestpart is process model underlying it

JH:           demo- (lite version from inside firewall - full runnable by anyone if

outside fw)

JH:           demowould normally invoke various services

JH:           demokeeps track of inputs/outputs from various services - various


JH:           choosingbabelfish - demo knows it takes string, offers selection of all

services that would deliver

JH:           astring.

JH:           demosaves the information about each svc in DAML-S

JH:           cancompose service of other known svc

JH:           sensorexamples: can select sensors by type, location, filter on


JH:           gridcomputing : can use very similar choreographies (and extended wsdl,

not soap) to WS

JH:           cantake composition of svcs and construct soap msg

JH:           wantsome way of saying "run this" to something that can

JH:           investigatedBPEL, WSCI (? pf) and they don't quite have the necessary


JH:           wantto pass more complex compositions

LG:           Weneed to be able compose things at run time ?

JH:           desireis to have language that allows this - bpel has too static a view

JH:           happyto have something that can say "go to directory and find out",

JH:           wedon't need to define how to talk to directories, but allow it to be


JH:           wantto have a tool that creates a workflow and hands it off - not so much

that we must do the

JH:           discovery

JH:           5-6years before having machine dynamic composition

KL:           Isthis feature addressed by WSCI Dynamic paricipation

JH:           Carefulnot to eliminate ability to have dynamic composition

DA:           severalhave mentioned this

MC:           subjectfor tomorrow group

       FrankMcCabe, Fujitsu

       Frank's position as opposed to Fujitsu's with a WSA bias (15 mins)

FM:           Hopesthis group will expand this model

FM:           reqs:combining web services - specify the relations, specify the message flows

              potentialfor automation - automatically verify, automatically drive,

              simplydocument what is happening

FM:           "anew generation of 'stub' code

FM:           showsdiagram of choreograph as state diagrams (model a process)

              examplehas several (not just 2) participants

FM:           showsa diagram of choreography "concepts" things like about, exchanges,


FM:           thiscaptures choreography as process, but misses tasks

FM:           trustan aspect of this that is important, but include intention, must be

applied to something (trust you to wash my car, not date my kid)

FM:           diagramcalled "layers of meaning"

              message,ontology, contract, constitution -- ontology defines meaning of


FM:           contractmeans actions, cause and effect

FM:           constitutionis who are the participants

FM:           task-orientedchoreography digram

              e.g.web service performs a task, task depends on another task, executes

              anaction.  Task description containdependency rules and the like

              choreographyspecifies the descriptions

FM:           dependencybased WS Chor - WS's combined by expressing dependencies,

              connectsto SW (OWL), do require rules w/variables

FM:           issues- cooperation, not technology. Semantics - goal v. process;

theoems v. development (support developer or the QA checker)

                     OWLspec is at

FM:           clarifiesthat Fujitsu is interested in the "task computing" area

PF:           asksquestion about state diagram choreography -- would things need to

know about each other in that?

FM:           answersby discussing make files, suggests that something like that may be

needed in the choreography world

LG:           questionwas about difference between goal and task.


       GregMeredith, Microsoft,

       Orchestration or Contracts (20 mins)

GM:           diagramshowing implementation connected to contract to contract to  


GM:           backendis General progr lang (turing), contract level is WSDL, but more


GM:           position- the "contract" portion of this space is considerly simpler than

the full language

GM:           conformanceplus compatibility yield correctness - lock free and leak free

GM:           thatis both interesting (theoretically) and business wise (note leaking


GM:           discusseddifficulty in wiring web service implementation - shows a live

lock situation

GM:           runsthrough an example - where things can be composed but leave need open

GM:           position(2)simple contract-like mechansisms are exhibited in the

literature (many citations)

GM:           ifthis WG created a contract langauge that guaranteed basic versions of

              thingslike this, it would be a big advance (at compatibility level)

GM:           WGcould ignore operational data

GM:           position(3)contract portion of this design space should be invoked by


GM:           position(4)- plan for success (what happens when LOTS of these out there)

GM:           somethingless than GPL is desirable - allows the query (analysis?) of


GM:           discussestrust issues

GM:           position(5) work needs to be carried out w/formal basis -- suggested

              "mobileprocess calculi"

GM:           comparessome of the formal models w/respect to completeness,

compositionality, parallelism, resources -- pi-calc only one tohandle all

of these (to date) (i.e. to have a model of each of these)

GM:           describessome challenges on process calculi

GM:           describessome issues w/mobility

FM:           whenyou say mobile what do you mean?

GM:           mobilitymeans "name shipping" in P-calculus model

UNKNOWN:      question aboutwhat conformance is?

GM:           contractis a projection, conformance is making sure the contract respects

the homomorphism

UNKNOWN:      question - yousay you see non-TM complete language as desirable?  

              Canyou explain further?

GM:           CFGor below allows a lot of things to be tested that aren't allowable in


JimH:         cart/horseissue - how do we make the trade-off decisions

GM:           lotof things we looked at drive us in this direction - example: bizTalk

              hadproblems because we couldn't handle some of these things

JD:           question- curious about relation of your talk to BPEL?

              BPELpushes high expressivity, now you're talking more limited - where is

              thebusiness case?

GM:           Letme be clear - we need GPL on implementation (e.g. BPEL) but we need

              provableproperties at the compatibility/conformance level

GM:           sowe have a different space than BPEL, and we also may get

discoverability out of this

GM:           Ifthe body moves to implementation over contracting, MS cannot


       Jean-JacquesDubray (invited talk)

JJD:          seeskey words that haven't been in other presentations, specifically

service oriented architecture. Give some elements on debatebetween

collaboration,executable business processes, choreography.

JJD:          comesfrom experience with BPS.

JJD:          XML,WS, and BPM will revolutionize the way we build applications, towards

              the"ultimate" component model.

JJD:          canwe do achieve for machines what the web has done for humans? Can

applications fetch data from remote services?

JJD:          immediateuse is for applications to better interact w/ environment.

JJD:          today,current app models (java, j2ee, C#) have limitations from

              programminglanguage perspective. E.g. Java doesn't have all constructs

necessary to take advantage of J2EE model. Other languages arerequired

forus to fully utilize J2EE. This complexity hasn't been taken out of the

programminglanugages. Choreography is a way to address this.

JJD:          Choreographyrepresents convergence -- b2b, eai, distributed computing,

J2EE / .net.

JJD:          Notionof provider / consumer is completely wrong for SOA. It's just a

particular case for use of web services, real model is peer topeer.

JJD:          provider/ consumer model will place severe restrictions on the model, we

should avoid this. This said, how do we define a SOA.

JJD:          tooksolution from OAG -- coarse components that interact with each other,

              exchangingmessages. e.g. customer service component / order mgmt


JJD:          theservices represent each one of the boxes in the scenario

JJD:          needliberty to place application, corporation boundaries wherever you

              like.What is impact on choreography design? This would be a big advance.

InPLM a manufacturer works with suppliers. You could have activities

localizedat supplier, team, different location in same company. From

choreographyperspective we don't care, it should be relatively neutral.

JJD:          thisopens new possibilities for application developers.

JJD:          toemphasize, intra / inter company message exchanges are different. No

shared memory (state alignment), legal aspects(non-repudiation).

JJD:          needminimum contracts in place to ensure that most cases are covered.

JJD:          SOAas application model slide. In an application model, much work being

done by MS, SAP, IBM on this aspect. Process engine appears with

applicationmodel itself. If you take the EAI concept, used to be separate

afterbuilding applications, now its covered as part of the application

model.Must provide facilities for the application developer to perform

integration,not after the application is developed.

JJD:          thiswill allow us to achieve process & data federation, representing

process / data collaborations. Notion of application becomesdifferent

because the middle tier and UI tier become spread acrossmultiple


JJD:          Keytakeaway -- WS-chor is major enabler of SOA. What are the elements of


JJD:          we'vebeen talking about contract and implementation. There are three

levels, using buyer / purchase order scenario. Roles in scenarioare

Buyer, Supplier, Order Entry, Manager, Billing. These rolesinteract via

message exchange. Most companies have similar scenario in place.

JJD:          referencein middle, which requires mapping & routing. Coupling is handled

by execution rules @ Supplier role.

JJD:          messagein this slide is collaboration between any 2 components. These

help define contracts between business partners, but they alsoapply to

collaborations between components within an organization. Notionof B2B

vs. EAI is arbitrary according to this kind of thinking.

JJD:          importantconcepts: role, executable business processes. Difference

between collaboration and executable business processes: bothare state

machines, but collaboration has no engine associated with it(nothing is

in the middle).

JJD:          nowan engine provides many roles (mapping, routing, "advancement").

Collaboration service is repsonsible for ensuring that incoming/ outgoing

messages are expected at a point in time.

JJD:          processengine monitors interactions, and can decide that a process has


JJD:          collaborationacts as business process firewall -- routing to existing

service, or filter it out. No execution, just there to monitorflow of


JJD:          backto picture, adding roles of process engine, you see entities that no

one talks about. This third level of "orchestration"is necessary. WS Chor

is about message exchange. You can choreograph message exchangesinternal

& external.

JJD:          atmodeling level they aren't different.

JJD:          Acomponent can interact with external entities. However, it's important

to distinguish 3 levels.

JJD:          example-- integration with SAP. integrating BOM with SAP. Step one,

synchronize item (add if not there already). Second, we cansynchronize

the BOM.

JJD:          withincomponent, there is additional logic that is different from

message. May be long running, but does not involve messageexchange.

JJD:          WSChor applies to 2 levels, lowest level may be different (BPML, BPEL are


JJD:          whatdo we choreograph? How do you do techincal binding? How do we handle

message exchange patterns (WSDL provides 4). Needed for BPSs tostart

business transaction, need two types of requests. This scenarionot

supported by BPSS.

JJD:          alsonotion in BPSS of signals. Message exchange is receiving signals,

generating response, sending response. If you think ofchoreography in

terms of patterns, it will be difficult to express even simple


JJD:          ifyou take away one idea, it's this chart. You have to choreograph

message exchange patterns. The choreography is much simpler ifyou express

it in terms of message exchange patterns. Chart is in terms ofroles, not

contracts, which can be generated automatically.

JJD:          alsonotion of protocol. in b2b, bpss requires signals (know that message

was processed by receiver) because response could come longafter request.

JJD:          youneed to know whether a response has come back. need to guarantee that

request is in the system of the receiver.

JJD:          onceyou have this in place, choreography needs to handle exceptions

(technical & business) that prevent request from going intosystem of


JJD:          transactionalbehavior is an aspect of choreography. With BPSS, people

don't complain about explicit compensation trx, because they are


JJD:          messagecontent needs to be defined. Is the SOAP model enough? Are there

other needs for collaboration?

JJD:          controlflow specification, countless attempts at this. BPSS is good at

this. Maybe it's time to consolidate all the differentapproaches into the

best one. could reference patterns for control flow to once andfor all

solve this problem.

JJD:          Ofthe three levels (collaboration, executable process, service / business

component), semantics are different. Example: fork atcollaboration has

choice of messages, one becomes invalid. As executable process,both can

be executed in parallel, or engine restricts behavior.

JJD:          Needto apply specific semantics, based on scope.

JJD:          Twoapproaches to technical binding. Neutral approach: roles that provide

techincal bindings. This approach allows easy definition ofcontracts.

JJD:          neutralform is better than reviewing 2 contracts for compatibility.

Ultimately the second approach doesn't allow for flexibility. Towork

together they must mirror each other.

JJD:          coulddo this with multiple WSDL services, providing greater flexibility.

JJD:          beyondChoreography, many other approaches: UMM, Business Collaboration

Patterns from COOL, REA


Business Entities (

JJD:          inweb services chor thinking, no one thinks about shared business objects

that each party may change state, how is this aligned betweenparties?

This concept could fit nicely atop WS chor.

JJD:          theseare completely different approaches.

JJD:          conclusions-- important to view WS Chor as Service Oriented Architecture.

Convergence of concepts. In terms of WS Chor, having mutual peerto peer

interaction is important. Scope should be whatever is puremessage

exchange (2 of 3 levels from above).

JJD:          B2Bdifferent from EAI. Do we need protocol as a standard step? All this

is about defining more metadata, but we'll be overloaded by itsoon. Need

to be careful about articulating all the layers of metadata.

DC:           MEPas units of what's being choreographed. Does this mean no one thing

has total knowledge about the transaction?

JJD:          simplecontructs like flow, to express MEP you express very complex

sequence, lots of constructs of chor language that would berepeated. It

would lead to greater simplicity if MEPs could be defined astypes, then


JJD:          otherwise,choreography gets too complex.

MC:           increasedlast week at WSDL group to seven patterns.

DA:           wemay want to put together a pattern languages based on primitives from

which the 7 could be built.

GM:           wantedto chime in w/ experience we've had. There are 2 kinds of

approaches to describing MEPs. Many familiar w/ sequence |parallel |

choice model. Corresponding notion of encoding agents that do verysimple

patterns (send msg, duplicate msg, forward msg). There are 7 ofthese, and

from these seven you can get any flow you want.

GM:           westarted down this path, but when simple flows compiled in this format,

they become very large. It is important to gain experience w/various

representations and learn their advantages & disadvantages.

GM:           theproof on this (minimality) is available by Yoshiisa on the web.




       FrankMcCabe, WS Architecture

       WSApositioning (15 mins) -- web servicesarchitecure

FM:           WSAgroup meeting for about 1 year, starting 04/2002. Now at point of

beginning to hone in on what WSA looks like.

FM:           sharethe architecture, drivers.

FM:           followingon JDs presentation, we view WSA as an SOA. P2P is of the

essence. Services are defined by messages that are exchangedbetween them.

FM:           notionof service, agent as compositional entity that represents a


FM:           goalsof architecture: interoperability between WS, integration with WWW,

capturing reliability, security, extensibility, manageability.

FM:           theseare like the primary goals of the architecture.

FM:           non-goals-- programming models, technologies, internal architecture of

specific WS. We aren't interested in showing you how to buildit.

FM:           notinterested in being specific about how messages or other descriptions

              areformatted. Architecture is a framework, not the detailed structure.

FM:           whatwe do own is the relationship between say SOAP and choreography.

FM:           reviewingConcepts & Relationships slide... Agent is computational

              resourceowned by someone. It requests / provides services.

FM:           aservice has a description, semantics, interface. The description of a

              servicedescribes these things and messages, and so on.

FM:           theone thing i didn't talk about earlier, is that agents & services are

              deployedelements. This is not complete story, but how we're incorporating

management into WS. Diagram is 2 dimensional diagram of coreconcepts that

arepart of the architecture, core relationships among the concepts. Core

technicalmeat of the architecture is an enumeration of this chart. We may

doa UML diagram to relate in more detail.

FM:           this allows us to defineconformance points.

FM:           wecan distinguish between may have & must have relationships, based on

              thesekey ideas in the architecture.

FM:           thisallows us to define constraints on the implementations.

GM:           supposeI have an architecture which doesn't have a description, and say

the service is its own description?

FM:           wehaven't yet identified where the mays and musts are. It might come to a

point that it's not a W3C service if it doesn't have a WSDLdescription.

FM:           inthe WSA document (in CVS tree, not an official release, expected may),

actual concepts are represented alphabetically.

FM:           example-- Message: read summary & relationships to other elements.

FM:           precisedetails may change, but this is the style we use to communicate

              whatwe mean by a Message. Another example: Legal entity.

FM:           eachterm has Summary, Relationships, Description.

FM:           nextpart of architecture is very important, the Stakeholder's viewpoints.

These address how architecture meets requirements.

FM:           thereare entry points from different perspectives (security,

introduction, etc.) elaborates on the entry point.

FM:           thiswill be presented in intgrated, non-alphabetical organization.

FM:           example-- Goal AG007 identifies manageability as a major goal. Describes


FM:           weidentify core conepts in architecture that relate to the goal.

FM:           examplefor AG007 is manageable element.

FM:           anotherdiagram, not yet agreed, management viewpoint, which illustrates


FM:           toenable p2p, we demonstrate enabling this in the architecture through

              MEPs,agents / services have identifiers allowing long running

              conversations,and that they have roles.

FM:           issues,some of the definitions need work. Responsibility of the WS chor

working group to have coherence with the WSA. This is abidirectional

relationship. WSA has to ensure that our requirements areaccounted for in

the architecture.

JH:           question-- choreography items seem contradictory?

FM:           noneof current WSA text will make it into the next iteration.

MC:           whatis the difference between choreography, conversations, and

orchestration is a major question to be resolved?

UNKNOWN:      question ?? JJD'spresentation mentioned business objects / resources not

              fullyworked out in BPSS. In architecture, this is an important idea, a

service has access to one or more resources. Is there a way totalk about

resourcesin choreography?

MC:           aresource is anything accessible via URI.

FM:           thisis a topic (trout ocean waiting for us).

MC:           importantpoint we still have to address.

GM:           howare you informing about ITU standards (e.g. manageability)?

FM:           canonly give a meta answer. Work on manageability is done by

representatives from IBM, HP, and Sun. To extent they take thisinto


FM:           realthing we want to capture is the core idea so we can fit it into the


MC:           thisis more from management view (tivoli, openview, etc.).

       Martin  Chapman & Steve Ross-Talbot,co-chairs WS Choreography

       Issues fromthe Chairs & discussions

SRT:          Wantsto start collecting issues. Have dubious task of going through

archives. Sheer volume / complexity of arguments was daunting.

SRT:          consolidateddiscussions, wants to set context. Martin will address


SRT:          wehave yet to put something up about the charter. Deliverables -- focus

is clear on process external description.

SRT:          wehave 2 years to create the deliverables. we don't have much time.

SRT:          charterstates that the language we devise must have composition,

              associations,message exchanges, and state management. Playing to the

focus, we'll see what stays in vs. falls out.

       charter ishere:

SRT:          landscape is confusion over choreography specs. see


SRT:          needsto have some clarity brought to bear on the situation by focusing on


SRT:          ourunderstanding of workflow / declarative modeling, and the web. WFMC,

W3C / HTTP / XML/ Semantic Web / Web Services (as businessneed),

BPMI(encoding workflow / process models in XML), BPEL. all theseled to

formation of choreography group.

SRT:          BPEL4WSis proprietary. IBM is not here. We don't know where it's going.

We have to deal with what we know in W3C (open, rules & regsfor W3C).

SRT:          formalmodels -- lots already said. Greg's chart summarized things well.

SRT:          modelsto be embraced, will not see life of day outside of our work, but

they will underpin everything we do.

Note - SRT showedslide which suggested Microsoft where not here (clearly slides were

       done lastnight).

Note - SRT shouldchange slide to reflect the fact that Microsoft are here in force

SRT:          wemust be very careful to be user driven. If we forget about the end

user, the result will be bad. I will actively talk to usercommunity,

asking them to contribute informally on archives.

SRT:          thereare different types of users (fast changing vs. slow changing needs,

complex vs. simple).

SRT:          ifall we do is service complex, we'll miss most companies who have

simpler needs. We need to manage both sets of users. When wedefine

requirements, must classify the type of user / requirements.

SRT:          inputs-- is wsci enough? If not, what does it lack? term definitions:

conversation, choreography, orchtestration?

SRT:          also,is wsci the right direction? is it too much?

MC:           whatfixtures do we need? How do we merge things together?

SRT:          needconsensus in this group, we may do mapping later to outside world.

DA:           pointsout that the concerns about WSCI also apply to BPEL & co.

SRT:          wheredoes semantic web fit? Interesting possibilities here.

SRT:          dowe leverage patterns (MEPs, etc.)

MC:           issues-- what is choreography about? where we will start fighting is when

we start to define terms. Even capitalization of words.

MC:           biggestthing is what is an external description? charter says to focus on

this. Need to nail this down first.

MC:           we'llgenerate issues and add more to the list later.

MC:           allthe items on the slide have been discussed today -- are transactions

part of it? Chor language needs syntax, but detail out of scope.

Compatibility checks (bi-simulations not decidable)? whathappens at

contractual level?

MC:           issueor fact -- if chor about implementation, aren't we inventing another

programming language?

MC:           ifwe don't make a distinction and it's turing complete, of course we're

              makinga programming language.

MC:           howdo we relate these things together? public description and private


MC:           separatingexternal conversations (inter-company boundaries) vs internal?

are they separate or the same? Today, everyone says we shouldn'tmake a

distinction, because you always have to consider trust, securityeven

between departments.

SRT:          namingthings public vs. private.  if iname something, does its internal

behavior remain private? Naming it does not say anything aboutits

internal behavior.

SRT:          whenwe do this work, naming is a key concept, so we wanted to raise it as

an issue.

GM:           dowe mean scope of naming?

MC:           manypeople want to do very simple things. Others need transactions,

security, processes running over months, hundreds ofparticipants, etc.

MC:           boeingneeding every part in the plane on the purchase order is different

than a travel agent booking a flight.

FM:           howmany PhDs do you need to understand it? LOL...

MC:           wehear about B2B. Is this important here? there are other application

areas than B2B. What level of granularity makes sense? What isthe

significance of the "B"? Is it too narrow?

MC:           manydiscussions about formal models. We'll probably see convergence quite

quickly. Other aspect is discussions about state vs. activitydiagrams.

Notion of graphical notation was ruled out of scope.

MC:           wewill not standardize any graphical notation.

MC:           wecan use whatever is suitable for this group.

MC:           whatis a conversation, a collaboration? Do we break down everything down

into 2 party exchanges? No, breaking it down doesn't alwayswork.

MC:           multipleparticipations, multiple conversations at the same time. also

discussion about negotiation of contracts.

MC:           thisis not an exhaustive list. Need to think about these issues and new

ones we must process.

mc:           wecan't make progress until we resolve execution issue. If you can

identify other burning issues, we'll post them.



(mc) today's focuswill be the "boring stuff", including requirements

(mc) first line ofbusiness -- when are conference calls?

(mc) two (equallyuncomfortable) alternatives: Tuesdays 1p PST or 7a PST

(pause torearrange lighting in the OCC)



first poll: 1pmPST = 18, 7am PST = less than 18

suggestion: howabout alternating times weekly?

response: that'seven worse -- it rules out scheduling anything in both of those times

suggestion:alternate days?

response: friday'stricky with time zones, mondays get difficult with long holidays

(mc) we couldpossibly consider alternating at some longer interval (possibly months)

(mc) conferencecall will be 1.5 hours every Tuesday at 1pm PST

first call will beTuesday, March 25th

(mc) call-indetails will be posted on the admin web site

       ACTION W3Cstaff to setup teleconf


(mc) second item:face-to-face meetings

(mc) although itwould be nice to coordinate with some of the other W3C working groups, that ishighly unlikely

(mc) it seems thatfour meetings a year would work: March, June, September, December

question: why can'twe overlap meetings?  there's a lotof overlap in what's being worked on

response:logistics with that many people wind up limiting where you can host such anevent

response: we canre-evaluate this at any time

(mc)rotation:  West Coast, East Coast,Europe, Oceana (?)

(mc) obviouslyknowing where we'll meet sooner is better, but W3C rules require at least 8weeks notice

WSA/WSD - 12-16May in Rennes, France

WSA/WSD - 28 Jul -16 Aug Toronto, Canada

point: conferencesin Oceana typically involve everyone travelling a long time

point: employeesof US companies can have difficulty travelling outside the US

point: Japanesecompanies tend to wind up hosting more often than is fair to them

(mc) Our two-yearschedule calls for only two meetings in Oceana

(mc) If it becomesa problem, nobody should feel pressured to host -- if nobody volunteers, we'llhave to find an alternate venue

question:  WW-Grainger isn't quite East Coast, butwill investigate hosting in June

(kliu) SAP may beable to host either in Europe or the US

(srt) Australia inDecember is a *lot* more expensive than other times of the year

I can also askabout Sun hosting in Burlington Massachussetts

question: is therea list of responsibilities for the host?

(mc) connectivity*at least* with HTTP

(mc) usual daytimestuff -- breakfast, lunch

(mc) dinner istypically self-paid

guides for hostingF2Fs:

(mc) usually thebiggest problem in organizing is connectivity

(mc) the number ofpeople presents a challenge; with the size of this group, classroom-stylesetups are more workable


(mc) third item --the work schedule


April 2003: 1stdraft of requirements and use cases

June 2003: WGapproved requirements doc (v1)

Sept 2003: 1stdraft of abstract spec

Dec 2003: 1stdraft of concrete spec

Feb 2004: approveupdates to requirements doc (v2)

July 2004: lastcall for all abstract/concrete specs

Aug 2004 - Marc2005: test suite, interop, primer, consolidate recs


(fmccabe) AFAIK,W3C has no policy about test suites and the like

(mc) No, but theyencourage it, and it's in our charter

(mc) we've triedto align the larger milestones with our F2F meetings

jhendler haschanged the topic to: WS Choreography f2f March 14, 2003

concrete vs.abstract specs: it seems like a good idea to get down an abstract spec, but arewe definite that there will be one concrete spec?

(srt) no, we mayhave multiple concrete specs

(kliu) thetimeline extends to Mar 2005, but the charter ends Dec 2004

(hugo+yves) goodpoint, but we have a rule that the group stays alive for six months after ourwork is over.  And this wouldn't bethe first time a working group was extended.

(mc) We should aimto be finished by December

(mc) Chairsappoint an editing team -- feel free to volunteer


(mc) Firstdocument will be the requirement document; we have two volunteers

(mc) (Abbie Barberand Dan Austin)

(daustin) I wantto work on the requirements spec, but I'd rather it not preclude working onother things


(cmcdonald) we'realso going to work on terminology as well, right?

(mc) I hadn'tthought whether we'd propose a separate glossary, or propose diffs/ammendmentsto the WSA glossary

(mc) there are afew classes of things: additions, redefinitions, overloading

(hugo) working inour corner and then merging into the larger glossary would probably be the bestapproach

(mc) Anytimeanyone has something they expect might help, send it to the list, BUT be awareof the IPR rules

(mc) Make it veryclear when you're just contributing background

(hugo) there'salready a set of definitions in the current glossary that we could either startwith or ignore

(hugo) will sendit to the list

              ACTION:Hugo to send choreography definitions to the list

(daustin) weshould probably as a group decide to adopt the issues approach that the WSA hasput together

(mc) what is thatprocess?

(daustin) someonereports an issue by sending it to a special mailing list

(daustin) anissues editor compiles the issues into a document

(daustin) someoneis assigned to resolve that issue by proposing a solution and working itthrough the group

(daustin) onceresolved, the issue editor updates the document

REF: WSA Issuesprocess URL:

(mc) W3C isencouraging groups to use bugzilla

(jhendler) thereare a couple of different types of issues, and document issues aren't somethingwe should spend a lot of time on right now

(jhendler) what wereally should spend time on now is how to deal with working group issues

(mc) right, we'vetalked about a public issue list, but we do need to deal with internal issuesas well.  perhaps bugzilla isworthwhile for this?

(mc) chairs takean action to think about the handling of issues

no, bugzilla wouldbe terrible for internal issues, I was NOT suggesting it.

in fact, I wassuggesting "NOT it"

REF: W3C Bugzillainformation URL:

Jim -- I think Iattributed the bugzilla comments to Martin.  Did I goof?

(mc) (demo ofbugzilla)

(mc) people shouldplay around with bugzilla

(jhendler) notsure whether I would advocate bugzilla

(jdart) seems likeother groups accumulate a lot of issues

(jdart) how do wekeep a list like this winnowed to keep it from growing out of control?

(mc) one approachis to do some kind of limited triage at each conf. call and F2F

(mc) dispose ofthe easy ones at conf. calls, and save the big ones for F2F meetings

qa deliverablesat:


we have to becareful to separate issues that must be addressed i.e. sent to the publiccomment list, and issues that do not require that level of formal treatment


I'm talking aboutQA.  This presentation was from theQA working group.

My point is tohighlight that QA is important, and we're committed to a certain level ofquality, and there are things to make our lives easier getting there.

Some workinggroups have been able to create good test suites.  It doesn't take a lot of effort if you do it right.

hugo slides at

There is a QAworking group, but they won't do the work of creating the test suite for us.

There aredocuments to guide us through the QA process.  The intended audience includes the chair, staff, and membersof the working group.  They are abit hefty.

Guidelines forwriting a testable spec:

* define scopeclearly

* specifyconformance policy

There is adocument describing these guidelines.

Most important forus is: how are we going to do that clearly?

Suggestion is toappoint a QA lead within the working group.

In the end,"everyone is responsible", but this person would be a focus.

REF: RFC 2119 -terms for use in specs:

Feedback isencouraged on these QA documents.

(Especially sincethese will be included in the W3C process)


(daustin) are theygoing to grandfather specs written before this process?

(hugo) there's noclear answer to that right now

(mc) Thesedocuments are really talking about testing and test suites.  QA includes issues and management andeverything else.  How do you writea test suite for an architecture?

(hugo) For somethings (like this working group), test suites are more relevant than others.

(hugo) Our nextstep is probably to appoint a QA lead.

(mc) We need aquality champion.

(mc) Volunteerswelcome.

(mc) There is asort of "field guide" to the QA documents, detailing who should readwhat, but it takes some reading to get to it.

(yves) We expectour mailing list to be very crowded.

(yves) Label youremail in the subject line (for instance, with an issue number), so people caneasily sort your email

(yves) If youreply and change the subject of your comment, change the subject line of theemail.

(jhendler) We havethreads like this now.  The emailarchive will keep track of the chain of replies, so change your subject freelyas you change topics.

(yves) Keep inmind that the list is public.

(mc) To reiterate,if you change topics, change subject lines.

QA presentation byHugo:

(fmccabe) Forthose people who aren't in the W3C list, you have to affirm that you want youremail archived.

(yves) This is inpart to control spam, but also to prevent people from not knowing they'reposting to a public list.

(jhendler) Somekind of subject-line annotation to administrative messages would be good

(mc) Those usuallycome out on the members-only list

(mc) A number ofpeople are in many groups, so they're overloaded with email.  Making a point at the end of a verybusy 300-reply chain of conversation is not always effective.

(fmccabe) Ouremails, wherever possible, should focus on documents, and contributions tothem.  If you have a suggestion fora document, prepare it as drop-in text.

(mc) Ourconversations are going to be structured around documents and issues.  Perhaps we should have a separate tagfor "theory" conversations.

(daustin) Maybethis is a good spot to talk about our use of XML spec(?).

(mc) That mightput people off right now.

s/XML spec/XMLSpy/

(daustin) Perhapswe should send some email to XML Spy about getting copies for members of thegroup.

(mc) Anythingelse?

(kaustin) Whatabout usage scenarios?

(mc) At the momentthat's lumped in w/ requirements. Perhaps we'll need two separate documents, but for now we're thinking ofthem as one.

contact at Altova(XMLSpy) is Alexander Falk



*** starting ***

(mc) Why the hell are we here?

It's clear that wehave a big decision: external only, internal only, both, or somethingdifferent.  Until we resolve that,it's pointless going on.

(mc) We'll have todo some iteration on that question. First we'll take a vote, then we'll have some discussion, and then comeback for more.

(mc) Non-bindingstraw poll: external only, internal only, both, don't understand, not preparedto say at this stage.

(jhendler) Can weget definitions of this terms?

(srt) No, thatwould be an "I don't understand"

(ygoland) Could weat least qualify "external only" to mean contracts, as per theMicrosoft presentation from yesterday?

(mc) WhyMicrosoft's?  Why not anotherpresentation.


(srt) Not preparedto say: 5

(srt) Don'tunderstand: 7

(srt) It's all thesame thing (both): 8

(srt) Internalonly: 1

(srt) Externalonly: 11

(srt) One group isgoing to pitch external, another internal, and a third one will pitchboth.  Part of the job is"what do you mean by internal/external"?

(srt) Assaf: both

(srt) YGoland:external

(srt) JDart:internal

(mc) Each groupworks on it for 1/2 hour, then a ten minute pitch for each with questions

(mc) Don't knowswill meet and elaborate on why they don't know and what they'd need to know inorder to make a decision.


       Externaland Internal (both)

(daustin) This isour first hard issue to take on.

(daustin)"Internal vs. External" -- it's not a versus

(daustin) We allneed to deal with external communications b/w compositions of web services

(daustin) Is itsufficient to just consider these communications?  We think not.

(daustin) Firstquestion: what does the charter say? It was written with 'creative ambiguity', so it can be read to supportboth positions.

(daustin) Nextquestion: what is the boundary b/w external and internal?  It's arbitrary, and your external is myinternal.  You'll end up doingboth, anyway.

(daustin) Thedistinction between internal and external doesn't help you solve anything.

(daustin) Next:what would it be like to only do external?

(daustin) We'dprobably need a formal composition model based on pi-calculus, an overall modeldescription describing internal and external, and a subset of that model forexternal only.

(daustin) Anothermodel would be to have the same formal model, and then two distinct sub-models:one external and one internal.

In the first case,it would be hard to do the formal model and the external model without the"in-between".  In thesecond case, we could just ignore the internals.

(daustin) In acollaboration, we need to know some minimal amount about the internal workingsof the other participants.  Withoutthis internal info, we'd be out of luck.

(daustin) Abehavioral description of web services would span internal and external.

(daustin) Thearbitrary inside/outside distinction doesn't serve a purpose for the users ofthe technology.

(daustin) If we'veonly got a definition of the external actions, we can't test the entireorchestration.

(daustin)Recursive composition can't be implemented with a strictly external model.

(daustin) Youcan't do a forward-looking spec for the external without having specified theinternal.

(daustin) How dowe describe multiple interactions across boundaries?

(ygoland) I don'tunderstand the difference between internal and external.

(daustin) That'spart of the point: it's an arbitrary distinction.

(mc) Summary: thedefinition of internal and external is arbitrary, so let's do all of it.

(ygoland) I stilldon't understand what we're talking about.

(arkin) We'retalking about the behavioral specification of web services.

(pfurniss) I maybe in the wrong group.  We'retalking about two different things: the behavioral specification of a webservice, and the B.S. of a web service user.

(ms) Let's talkexternal before we discuss.

(??) Breaksomething into an interface/implementation, and there's the same underlyingmodel behind them both.  How do youdo one without the other?

(daustin)Nightmare scenario: if this group didn't chose to define internal processing,standards would still emerge in that arena.

(afletcher) We mayhave three things, instead of two. One is the global model of the whole process.  Another is a description of the individual endpoints(configuration).  The external infois the message sequencing info.


(ygoland)Presenting the discussion in the external-only group.

(ygoland) Don'tlike the terms internal/external.

(ygoland) The keydistinction is a matter of policy. For example, say someone sends you and order, and you check theircredit, and then respond.

(ygoland) Oneissue is visibility: you want to tell your customer that you can accept ordersand respond to them, but the credit check is none of their business.

(ygoland) I wantmodular technology so I can describe my internal process (including the creditcheck), and at the same time describe to my partner how we fit together.

(mc) Question: wecan do this in WSDL today.

(ygoland) Notreally, because WSDL can't describe the ordering of the serviceinvocations.  It can say thatmessages exist, but not the other stuff.

(ygoland) So whatI want is to be able to send out something that says, "this is how youtalk to me"

(ygoland) Discussionmoved on to the way you'd represent this external view as a state diagram, andthe question of: how do you specify the transitions between the states?  Programmatically?

(ygoland) I don'twant to put code in my model (like XPath).

(ygoland) Howwould you use this?  You wouldgenerate skeleton code.  You couldalso do runtime validation?

(nick) This goesagainst Greg's presentation from yesterday, and this goes againstpi-calculus.  You don't care aboutdistribution or about parallelism. What's the value?

(ygoland) If youlook at BPSS, it expresses all roles and states globally.  It includes conditions, which I don'twant to do.

(ygoland) A lot ofdiscussion was spent on the difference between interface and implementation.

(ygoland) Can Ichange my implementation, without changing my interface?

(ygoland) If Ican't separate them, we have to define a new programming language, or take anexisting one and refine it.

(mccabe) Much ofthe heat of the discussion came from what the semantics of the interface weregoing to be.  How much detailbelongs in it?

(ygoland) If Isend you a message, and part of it is my email address, but I don't want you toshare it with anyone, is the expression of that issue within the scope of thisworking group?  Personal opinion:start small.

(daustin) I agreethat you should be able to change the implementation without changing theinterface.  But our distinction isnot along those lines.

(daustin) So we'retalking about issues that don't entirely match up.

(daustin) What weneed to describe is what happens when web services interact witheachother.  The "both"group wanted to cover the whole chain.

(mc) I understandthe "beefing up WSDL" approach. Where's the choreography angle in that?

good notes!

(nick) But isn'tthis BPSS?


(mc) So this isextended WSDL, basically.

(ygoland) No, thisis a global view of the entire thing -- all participants.

(mc) So doesn'tthat constrain the implementation?

(ygoland)Yes.  That's the point.

(nick) I agreewith the BPSS-style third-party view. But you're making the same argument that the "both" group is.

(ygoland) Are wegoing to try to create a description that fully describes all aspects of thebehavior of a service?  This isgoing to include code?  BPEL iscode.

(jdart) One of theissues here is the desire to separate interface and implementation.  Another issue is whether the languageused to describe the two are the same.

(jdart) We cancapture a certain level of use case with nothing more than a directedgraph.  Additional features, likeconditional transitions, add complexity. WSCI/BPEL are advanced in complexity and functionality.

(jdart) So theconcern is: do we need a Turing-complete language?

(jdart) Do we needto do computation, especially on message content, including variables, in orderto express our use cases?  Thisdepends on the use cases, and we don't have any!

(daustin) The"both" group thought that the formal model and the internal modeldescription would be turing-complete.

(ygoland) Thereare many use cases that a simple state-transition diagram couldn't possiblyhandle, but even the ones it can handle are *very* useful.

(arkin) Whatyou're describing is an orchestration, and it's not computationallycomplete.  If you add XPath, itbecomes computationally complete.

(mc) Say we decideonly to do the external, and someone says, "what if we add this one tinyfeature"?

(ygoland) Puttingin XPath doesn't solve your problems, it starts them.  You become a programming language, and a full-fledgedenvironment, and you have to define your application platform.

(ep) Why would youadd XPath so that someone else could compute your state?  I know what state you're in by what yousend me.

(ygoland) Oneclaimed benefit of XPath is that we can check on eachother.

(arkin) So youclaim languages like BPML are impossible?

(ygoland) No, Iclaim that they're programming languages, and they're a basis for*portability*, rather than *interoperability*.

(nick) So what are the basic elements of interoperability?

(mc) It's clearly not what goes on the wire, but it's a higher-level application-defined sort of thing.

(nick) But where does it stop?

(jhendler) This discussion still sounds like position statements, rather than discussing the implications of the decisions. Saying "we couldn't do X" doesn't really give us the picture.

(jeff) If you make a firm condition that you'll go so far and no farther (i.e. "noXPath"), there's no smooth path for improvement.  You ought to have an understanding of how to expand your usecases over time.

(ygoland)Sometimes you don't have those smooth paths.  Part of the reason this XPath discussion is so heated isbecause it is such a big leap.

(arkin) BPML andBPEL prove that you can use the same language for both implementation and interface.  If either of those is standardized, then there will be no reason to use a W3C choreography.

(ygoland) The morefunctional language doesn't always win. Our challenge is not just to provide functionality, but to show our customers what they don't need to do.

(srt) Aninteraction pattern: order goes in, unspecified number of interactions comeback.

Daniel sez: Todayis Albert Einstein's birthday! (Al would agree with the 'both' group)

(srt) This iscritical to financial services.

what is the 80/20?

(ygoland) They'redoing without it now.

(mccabe) In theexternal view, the "formal model" shows up in the interface.

Steve -- yourfinancial services example was a good one, but it's not just FS.  Established standards like RosettaNetuse communication patterns like the one you described.


(lgreski) Speakingfor the undecideds ...

(lgreski) Wehaven't completely defined the business problem we're trying to solve, anduntil we do that, we're out of luck.

(lgreski) What isthe difference between internal and external?

(lgreski) Is adistinction necessary?  If so, whatare the implications?

(lgreski) As aconsumer/developer, what do I need to know to use a web service choreography

(lgreski) Are wetrying to develop a language to tie together web services?

(lgreski) Whatterms/definitions do we need to be decided on?  Choreography, orchestration, composition ...

(lgreski) Doesthis externalization of service behavior require access to the internals?

(lgreski) Maybethere's something that relates an interface to an implementation?

(lgreski) How dowe ensure that we have a set of abstractions at different levels of granularityso the relations between the levels is complete and well-formed?

(lgreski) Does theinternal/external distinction mean anything across intra-/inter- companyboundaries?

(lgreski) Ifchoreography must be internally consistent, how can we only view it externally?

(lgreski) What'sthe theoretical foundation for choreography?  Does this mean anything for the internal/externaldistinction?

(lgreski) Doescompositionality require an internal view?  For real-life applications, we want to assemblechoreographies at runtime.

(lgreski) HolyGrail for end-users: build and develop complex services without having toinvolve large teams of coders.

(lgreski) Is thething that is composed (the choreography) in itself a service?  Does this have implications forinternal/external view?

(lgreski) How canwe understand what we're trying to do in the context of existingspecifications: BPML, BPEL, BPSS?

(lgreski) What arethe technical problems we're trying to solve.  How do they relate to the business problems?  Are there different problems forinternal vs. external?

(jdart) Question:say more about customer-specific services and composition at runtime.

(lgreski) WW Graingersells maintenance supplies. Customers vary in size from F500 to small manufacturing or constructionconcerns.  They all have differentprocurement processes.

(lgreski) Our datashows that 40-60% of the cost of an item is the process cost around purchasing.

(lgreski) To helpour customers reduce costs, we understand their processes and help themeliminate steps.  We supportelectronic marketplaces, which are arguably standard, but adding customers tothem is still painful.

(lgreski) We wantto look at a customer's process and expose our services electronically.  We want to choreograph interactionswith our customers for catalog queries, order management, etc.

(jdart) Is thatreally composition at runtime?

(lgreski) We'dlike our salespeople to be able to interactively develop a process.

(jdart) Anotherexample is offering an order to the best of N suppliers.

(daustin) Thereactually is a good case for runtime composition.  Say a customer wants part X, and we want to be able tofallback from one supplier to another, or one part for another.

(ygoland) Twodifferent issues: dynamic membership, where I don't know how many people aregoing to participate, or I want to actually pull down another choreography andrun it.

Sure, if we've gotanother volunteer I'd love to start making trouble.  :)

would it be trueto say that maybe now is the time to go back to basics and start compiling usecases?

(fm) There is noreason why we cannot review use cases now

(mc) greg made itclear that BPEL does not do *contracts*

(jd) has questionsabout BPEL

(jd) why doesabstract BPEL exist?

(jd) if we do dosomething like it how does it paly w/ BPEL?

(jd) brings outuse cases that exist..

(jd) statesproduct example

decide uses casesand terminology

group decides towork on use cases and terminologies (definitions)

(mc) asks dif.between choreography and orchestration

(??) orchestrationis more control, choreography is description of what needs to be done.

(nick) is there aformal model?

(nick) pi-calculuscan capture both internal/external

(mc) we are insolution space now, back to problem..

(steve)orchestration has controler

(fm) orch is arealization of  a choreography

(duncan)composition vs. chor, composition is when you're actually building something

Webster definitionfor Orchestration: "harmonious organization <develop a world communitythrough orchestration of cultural diversities)"

(assaf)choreography can be a choreograph of orchestrations

Webster definitionfor composition (those that make sense for us): "3 : mutual settlement oragreement

4 : a product ofmixing or combining various elements or ingredients

(??) what are wetrying to decsribe, we need to agree on terms

The W3C usesmerriam-Webster online dictionary for its definitions

(mc) presents chormodel on board (flow), and then orch model (hub-and-spoke)

(mc) semanticallyequiv.

I got these fromMerriam-Webster Online

(mc) does anyonedisagree w/ dropping *orchestration* as a term?

(mc) orchestrationhas state (?)

(lg) have we drawnany conclusions?

(mc) word *orchestration*is banned from this group

(steve) centralcontroller model is not precluded


(mc) use cases,like idea of developing a set, trivial to more complex

(mc) could dosimpler cases (e.g. Chroreography 1.0)

(mc) presents 1stuse case on board, a reservation system

(mc) new entity(e.g. airline) wants to plug into the system, what does it need to know?

(mc) have WSDLsand what other artifacts?

(mc) addsstock-quote use case as simple case

(steve) adds carreserv. system to travel reservation system

(fm) adds movie& a pizza case, agent puts together an evening of dining, enter., etc. forcustomer

(fm) a *know typesbut not instances* case

(jd) given anactor what is it's view of the system?

(da) rememberaudience is implementers of the services

(pl) presents*provisioning* use case

(pl) moreprecisely the GM new hire provisioing use case

(YG) brings upprovisioning example using *UAN*, asks about human interaction issues, and HTMLand SOAP

(mc) clearifiespl's case ... an iterative process in which goal is unknown

(yg) asks how usecase reflects back into requirements?

(yg) asks how wecan accomidate system change

(jd) prov exampleis a good one, interesting aspect is furniture vendor negotiation

(lp) issend/recieve model rich enough?

(steve) presentsclient/server example

(steve) think ofidle server and busy server, trying to tease out differnces between cws andstate

(da) need todefine set of primitives to build upon

(fm) presentsdoctor's office (receptionist, patients, doctors)

(fm) conversationsbetween recept and doctors, and recept and patients,  doctors and patients

(fm) in lucian'spaper(?)

(jd) needdescription when you have multiple actors that need to know how to interact w/a system

(fm) setting bartoo high

(yg) brings uplegacy issue

(yg) figuring outhow to structure for white, black, gray box scenarios

(mc) anysuggestions on what to next?

(lg) recap of usecase purposes

could lp pleasepost these recaps?

sorry, I mean lg



              ACTION:Presenters of use cases to write them up

(steve) takesaction item to capture use cases

       ActuallySteve took an action item to capture his use case not all others.

client / serveruse case: basic communication pattern between two machines. How do we dscribeinteraction of one particular service vs another at the point at which wecompose them. Pattens of interatctions they support, and composition of thoseservices.  (e.g. open, close,request / reply). How do we capture the different patterns of interactionagainst the state of the service?

Action: write upuse cases

reservation usecase: new airline wants to join reservation system. Need to know the artifactsthat are required by the system / airline in order for airline to join andparticipate in transactions on the system.

recommendationsystem: provide recommendations, package restaurants, movies, etc. into nightout for customer. Addresses dynamic membership problem, processes are known,it's a question of adding a new restaurant, movie.  At the beginning of the interaction I don't know whichrestaurants / movies to access.

doctor office:multiple service, single queue. dynamic instance allocation. Multiple actorsthat interact with a service in a predictable, reliable way.

provisioning:Coordinating iterative communications between company and external entities,where the goal is unknown in advance, or the goal changes based on results ofindividual process steps.

Also, changingdefinitions of process(es) at runtime.

Negotiation /proposal, counterproposal.

(da) can we breakup into diff levels of abstraction?

(da) here is thestack bottom up:  MEP, WSCI,Metadata (policy), Global Process

(da) expressesneed to get handle on types of probs were are trying to address, use stack as apoint of discussion

(da) MEPrepresents the basic 7 messages

(da) metadatarepresents business policies related to the message (e.g. we won't sell yourname to

(da) MEP -messages passed and what is contained, WSCI - programming, Metadata -assertions, overall view of the chain of msgs or events

(da) globalprocess represents the entire business process

(da) wscirepresents one participant's perspective on its programmatic abilities

(da) globalprocess sequences multiple participants (services)

(Tony) is notconvinced we wnat MEP layer

(da) another wayto summarize, as levels of abstraction: MEP = message, WSCI = service, metadata= contract, and global process = composite.

(yg) signals areimportant and need to included

(mc) we have to beconsistent w/ a version of SOAP and a version of WSDL

(yg) is multipleoccurances of MEP / Choreogrphy pattern significant?

(mc) suggestswrap-up

(mc) suggestion:given 1st poll, there is a majority for external, so maybe we should startlooking at external

(Jeff) perhapsgood idea to start w/ pi-calc

(Steve) expressesneed to elaborate on use cases

(mc) suggestsbuilding requirements from the use cases

(mc) answers thatthere is no concensus on what is *external*

(yg) BPSS giveexternal view w/ no logic

(mc) closingcomments, end of f2f