Stanford Universityeil.stanford.edu/ficas/FICAS032703.pdf · Primavera P3 Vite MS Project 4D Viewer ... notification_svc = SETUP ... 30 Stanford University Event Dependency Graph

Stanford UniversityEngineering Informatics Group (http://eil.stanford.edu)

Composition of Engineering Web Services

David Liu Department of Electrical EngineeringJim Cheng Department of Civil and Environmental EngineeringJun Peng Department of Civil and Environmental EngineeringKincho Law Department of Civil and Environmental EngineeringGio Wiederhold Computer Science Department

Stanford UniversityStanford University22

Agenda

• Ubiquitous Computing Environment

• Service Integration – FICAS


Ubiquitous Computing Environment


Ubiquitous Computing – An AEC Scenario

3D/4DModeling Tool

Set

ProjectPlanningTool Set

Designers

Project Managers

On SitePersonnel

On-LineInformation Store


Distributed Engineering Service and Integration

Mediators (Content and Access)Information Exchange (DBMS, PSL, IFC, XML)

Service Integration (FICAS)

Engineering Application Services


An Integrated Service Environment

Designers

Project Managers

On Site Personnel

CommunicationNetwork

Data IntegrationMobile Classes

SupplyChainTools

Autonomous Service Wrapper

ProjectPlanning

Tools


3D/4DModeling

Tools


IntegratedWork ProcessesUbiquitous Access

Data Integration

Service Integration


Ubiquitous Computing Environment – Three Issues

• Ubiquitous Access– Wireless Network Infrastructure– Wireless Devices– Device-independent Software Services

• Data Integration

• Service Integration


Supporting Multiple Devices Via Active Mediator

Messaging Bus / Internet

PDALaptopWorkstation

Information Content

Information Abstraction

Information Client

ActiveObjectQuery

SourceQuery

SourceContent

Client-SpecificContent

ObjectConstructor

SourceInformation

Services

Active Mediator

XMLObjects

XMLStyleSheet


Active Mediator in Action

Active Mediator

MobileClass

Fetcher

MobileClass

Runtime

ExceptionHandling

MobileClassAPI

Library

InformationClient

Mobile ClassCache

ObjectConstructor

DataMediator

SourceInformation

Services

Queries

MobileClass

SourceObject

ResultObject

Request +Mobile Class

MobileClass


Using PSL As Standard Exchange Language

PSLPSL

PSLWrapper

PSLWrapper

PSLWrapper

PSLWrapper

PrimaveraP3

Vite

MSProject

4DViewer

Database(Oracle 8i)

Translator


Using FICAS For Service Integration

FICAS Buildtime

AutonomousService

Directory


CLAS Program

FICASControls

AutonomousService

Autonomous ServiceMediator

AutonomousService


AutonomousService


SoftwareApplication


FICAS RuntimeFICAS Buildtime

MegaserviceControllerMegaservice

ControllerMegaserviceControllerMegaservice

Controller


FICAS(Flow-based Infrastructure for Composing Autonomous Services)


Service Composition

Coding

Integration

1970 1990 2010

Coding

Integration

1970 1990 2010

AutonomousService

AccessProtocol

OperatingSystem

Host

A

A

A

AutonomousService

AccessProtocol

OperatingSystem

Host

N

N

N

Physical Communication Backbone

MegaserviceConceptual Composition of

Autonomous Services

AutonomousService

AccessProtocol

OperatingSystem

Host

B

B

B

Megaservice Controller

......


Service Composition Infrastructure

• A Method to Integrate Software Applications– A access protocol for desired software functionalities– ASAP (Autonomous Service Access Protocol)

• A Method to Specify Functionality– A compositional language– CLAS (Compositional Language for Autonomous Services)

• An Environment to Execute Composed Services– A runtime environment that coordinates control-flows and data-flows– FICAS (Flow-based Infrastructure for Composition Autonomous

Services)


ASAP(Autonomous Service Access Protocol)


Autonomous Service Metamodel

• Service Core– Represents the core service functionality– Wraps an existing software application

• Data Containers– Handle input and output data– Form data-flows– Enable distributed data-flows

• Event Queues– Handle inquiries and issue requests– Form control-flows– Enable asynchronous service invocations

Data-flow

Control-flow

Input Data Container

Output Data Container

Input Event Queue

Output Event Q

ueue

Service Core


Autonomous Service Access Protocol (ASAP)

• ASAP– A light-weight, asynchronous and non-blocking event-based protocol– Defines how autonomous services respond to events – XML is used as transport medium for both control and data

• ASAP Events– SETUP, TERMINATE: Initialization / termination of autonomous services– INVOKE: Invocation of autonomous services– MAPDATA: Management of data-flow between autonomous services– CONTROLFILE: Execution of megaservice control files


Autonomous Service Wrapper (ASW)• Purposes of ASW

– Facilitate wrapping of software applications into autonomous services– Implement data containers and event queues– Implement ASAP protocol



Input Event Queue

Output Event Q

ueue

Service Core(ASAP Support)

Megaservice C

ontroller

EncapsulatedSoftware

Application

AutonomousServiceWrapper

public interface ServiceCore{

public boolean setup(Container inc,Container outc,FlowId inf);

public boolean execute(Container inc,Container outc,FlowId inf);

public boolean terminate(Container inc, Container outc,FlowId inf);

}


CLAS(Compositional Language for Autonomous Services)


CLAS

• Compositional Language for Autonomous Services– A high-level declarative language– Based on CLAM language developed in CHAIMS– Simple (Intended for domain experts, NOT technical experts)– Separation between composition and computation

• Features– Decomposition of a CALL statement into 4 primitives

• SETUP, INVOKE, EXTRACT, TERMINATE– Control primitives

• IF … THEN … ELSE• WHILE

– Mobile class• For specifying computational logic


Mobile Class for Specifying Computational Logic

• Mobile Class– Java based– Dynamic routines that performs

complex computational logic– Reusable

• Example of Mobile Class– Relational operators

σ cond (A), π attr (A), A ><cond B– Arithmetic operators

+, -, ×, /– Data aggregation and abstraction– Type conversions

/* Specification of a type conversion mobile class */

public class int2float implements MobileClass

{

public DataElement execute(Vector params) {

DataElement arg =

(DataElement) params.firstElement();

int val = arg.getIntValue();

return new DataElement().setValue(

new Double(val).doubleValue());

}

}

/* Using m-class in a CLAS program */

floatnum = MCLASS("int2float", num)


FICAS Buildtime

Executable

CompilationCLAS

Compiler

FICASControls

JavaCompiler

CLASPrograms

MobileClass

SourceCodes

MobileClasses

Source

CompositionalSpecification

ComputationalSpecification


Sample CLAS Program 1

SchedulingDemo "http://ficas.stanford.edu/Megaprogram"{

/* Setup Services */psl_svc = SETUP("SIPsl")p3_svc = SETUP("SIP3")notification_svc = SETUP("SINotification")

/* Invoke and extract information from PSL Service */psl = psl_svc.INVOKE("to-psl", "CEIL")ceil = psl.EXTRACT()

/* Invoke Rescheduling Service */p3 = p3_svc.INVOKE("reschedule", ceil)ceil2 = p3.EXTRACT()

/* Store information using PSL Service */oracle = psl_svc.INVOKE("to-oracle", ceil2)status = oracle.EXTRACT()

/* Invoke Notification Service */notif = notification_svc.INVOKE("171.64.55.32", 8250, status)

/* Terminate Services */psl_svc.TERMINATE()p3_svc.TERMINATE()notification_svc.TERMINATE()

}


FICAS Runtime


FICAS Runtime Architecture


ServiceCore


ServiceCore


AutonomousService

Directory

FICASControls

MobileClasses


ServiceCore


From FICAS

Buildtime



ASAP Event Receiver

Outgoing Event Pool

FICASControls

Control Manager

FlowDependency

Table

VariableCache



FromAutonomous

Services

Input Event Queue

Output Event Q

ueue



Service Core

Active Mediator

ToAutonomous

Services

FICAS Control Sequence

……

<INVOKE><INVOCATIONHANDLE>Invocation1</INVOCATIONHANDLE><SERVICEHANDLE>Service1</SERVICEHANDLE>

</INVOKE><INVOKE><INVOCATIONHANDLE>Invocation2</INVOCATIONHANDLE><SERVICEHANDLE>Service2</SERVICEHANDLE>

</INVOKE><EXTRACT><VARIABLE>A</VARIABLE><INVOCATIONHANDLE>Invocation1</INVOCATIONHANDLE>

</EXTRACT><EXTRACT><VARIABLE>B</VARIABLE><INVOCATIONHANDLE>Invocation2</INVOCATIONHANDLE>

</EXTRACT><INVOKE><INVOCATIONHANDLE>Invocation3</INVOCATIONHANDLE><SERVICEHANDLE>Service3</SERVICEHANDLE><VALUELIST><VARIABLE>A</VARIABLE><VARIABLE>B</VARIABLE>

</VALUELIST></INVOKE>

……


Service Integration Models

M

S1

S2 S3

S4

M

S1

S2 S3

S4

M

S1

S2 S3

S4

M

S1

S2 S3

S4

(a) Centralized Control-flowCentralized Data-flow Model

(1C1D)

Control-flows

Data-flows

MegaserviceM

AutonomousServices

S

(b) Centralized Control-flowDistributed Data-flow Model

(1CnD)

(c) Distributed Control-flowCentralized Data-flow Model

(nC1D)

(d) Distributed Control-flowDistributed Data-flow Model

(nCnD)


Data Dependencies within Megaservice

/* Megaservice specified in CLAS */

Invocation1 = Service1.INVOKE();


A = Invocation1.EXTRACT();

B = Invocation2.EXTRACT();

Invocation3 = Service3.INVOKE(A, B);

C = Invocation3.EXTRACT();

Invocation4 = Service4.INVOKE(C)

D = Invocation4.EXTRACT();

Invocation1 Invocation2

Invocation3

Invocation4

A B

C

D


Event Dependency Graph – 1C1D

INVOKE(Service1)

INVOKE(Service2)

MAPDATA (A, Service1,Megaservice)

INVOKE(Service3)

MAPDATA(C, Service3,Megaservice)

MAPDATA(B, Service2,Megaservice)

INVOKE(Service4)

MAPDATA(D, Service4,Megaservice)

MAPDATA (A, Megaservice,

Service3)

MAPDATA (B, Megaservice,

Service3)

MAPDATA(C, Megaservice,

Service4)

Service 1

Service 2

Service 3

MegaService

Service 4


Event Dependency Graph – 1CnD

INVOKE(Service1)

INVOKE(Service2)

MAPDATA (A, Service1,

Service3)

INVOKE(Service3)

MAPDATA(C, Service3,

Service4)

MAPDATA(B, Service2,

Service3)

INVOKE(Service4)

MAPDATA(D, Service4,Megaservice)

Service 1

Service 2

Service 3

MegaService

Service 4


1C1D v.s. 1CnDINVOKE

Dest: Service1

MAPDATAData: AFrom: Service1To: Local

MAPDATAData: AFrom: LocalTo: Service3

INVOKEDest: Service3

MAPDATAData: CFrom: Service3To: Local

MAPDATAData: CFrom: LocalTo: Service4


MAPDATAData: BFrom: Service2To: Local

MAPDATAData: BFrom: LocalTo: Service3



MAPDATAData: AFrom: Service1To: Service3


MAPDATAData: CFrom: Service3To: Service4


MAPDATAData: BFrom: Service2To: Service3


Invocation1:

Invocation2:

Extract A:

Extract B:

Invocation3:

Extract C:

Invocation4:

(a) Centralized Data-flows (b) Distributed Data-flows

Extract D:MAPDATA

Data: DFrom: Service4To: Local

/* Megaservice specified in CLAS */



A = Invocation1.EXTRACT();

B = Invocation2.EXTRACT();

Invocation3 = Service3.INVOKE(A, B);

C = Invocation3.EXTRACT();

Invocation4 = Service4.INVOKE(C)

D = Invocation4.EXTRACT();


Performance Evaluation – Apache SOAP v.s. FICAS

SwitchMegeService

S1produces

and returns astring value

10mbps

S2consumes a

string

out

10mbps

in

(LAN) in = 10 mbps; out = 10 mbps(802.11b) in = 2 mbps; out = 0.5 mbps

ForwardingData { a = S1(size) S2(a) }

SingleCall { a = S1(size) }


Megaservice Performance on LAN Setting

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

0 100 200 400 800 1600 3200

Data Volume (KB)

Meg

aser

vice

Exe

cutio

n Ti

me

SOAP (Single Call) SOAP (Forwarding Data) FICAS (Forwarding Data)

FICAS incurs higher control-flow cost

SOAP incurs higher data-flow cost


Megaservice Performance on 802.11b Setting

0

10000

20000

30000

40000

50000

60000

70000

80000

1 2 3 4 5 6 7

Data Volume (KB)

Meg

aser

vice

Exe

cutio

n Ti

me

SOAP (LAN) SOAP (802.11b) FICAS (LAN) FICAS (802.11b)

SOAP creates bottleneck on the megaservice

communication link

FICAS is little affected since data-flows are distributed


Using Active Mediation for Performance Optimization

Example:Type Conversion Using Broker Services versus Mobile Classes

M

S1

(a) Type Brokers

T1

T2T1_T2 T2_T3

S2

T3

M

S1

(b) Type Mediation Mobile Classes

T3 S2

mobile classT1_T2

mobile classT2_T3

Control-flow

Data-flow

J. Ockerbloom, "Mediating Among Diverse Data Formats", Carnegie Mellon University, PhD. Thesis, 1998.


Executing Mobile Class on Active Mediator


MobileClass

Fetcher

MobileClass

Runtime

ExceptionHandling

Mobile ClassCache

Mobile ClassRepository



MobileClassAPI

Library

Active Mediator


A Megaservice with a Mobile Class

SwitchMegeService

S1produces

and returns astring value

10mbps

S2consumes a

string

10mbps

Invocation1 = S1.INVOKE(size) A = Invocation1.EXTRACT()

B = MCLASS ("FILTER", A)

Invocation2 = S2.INVOKE(B)

10mbps

Mobile ClassFILTER


Performance Comparison for Mobile Class Placements

0

2000

4000

6000

8000

10000

12000

100 200 400 800 1600 3200

Data Volume (KB)

Meg

aser

vice

Exe

cutio

n Ti

me

Mobile Class on S1 Mobile Class on S2 Utility Autonomous Service


Distributed Component Models

Client-ServerActive Mediation

Client-ServerClient-ServerInvocation Model

Sync / AsynchronousSynchronousSync / AsynchronousSynchronicity

URLURLProxy ReferenceRemote Reference

Procedure CallProcedure CallMethod CallLanguage Paradigm

DistributedCentralizedCentralizedDataflow Model

Autonomous Service Directory

UDDI (Universal Description, Discovery and Integration)

CORBA Naming ServiceLocating Services

N/AWSDL (Web Service Description Language)

CORBA IDL (Interface Description Language)

Service Description

TCPHTTP, SMTPIIOPTransport Protocol

XMLXMLCDR (Common Data Representation)

Data Representation

FICASSOAP (Web Service)CORBA


FICAS Summary

• Objective– Investigate revolutionary approach to large-scale software composition

• Approach– Develop and validate a distributed data-flow based service composition

framework

• Contributions– Protocol (ASAP) support for constructing autonomous services– A high-level language (CLAS) that separates composition from

computation– Performance optimization with data-flow distribution– Active mediation to extend the capability of the compositional language

and to facilitate data-flow optimization


Demonstration


Putting It All Together – Demonstration

PSLXML

PrimaveraP3

Oracle 8iRelationalDatabase

4D Viewer

Active Mediator

Palm DesktopBrowser

MicrosoftProject

MicrosoftExcel


Review Design in 4D Viewer

4D Model Taken on 3/25/2001 From 4DViewer


Review Schedule in Primavera


Review Schedule in Microsoft Project


View Schedule on Site

http://med...!! HistorySCHEDULE

Review the schedule and make appropriate updates by changing thevalue in duration:

SCHEDULEIDSTARTDATEDURATION

18T1-3320101-31-2001 1.…………………….. Update

18T1-3324102-01-2001

http://med...!! History

SCHEDULE



18T1-3320101-31-2001 1.…………………….. Update

18T1-3324102-01-2001


Modifying Schedule On-site




18T1-3320101-31-2001 40…………………….. Update

18T1-3324102-01-2001




18T1-3320101-31-2001 40…………………….. Update

18T1-3324102-01-2001

Change duration of activity18T1-33201 (“Erect Roof Elem 1”)From 1 day to 40 days


Invoke Rescheduling Megaservice

Network

ReschedulingMegaService

RescheduleService { model = PSLModel(modelname, 'oracle-to-psl') new_model = P3Scheduling(model, 'reschedule') PSLModel(new_model, 'psl-to-oracle') ExcelService(new_model, 'show') ChangeNotify(modelname) }

PSL

PrimaveraP3

PSLModel

Service

P3Scheduling

Service

ChangeNotify

Service


Review Modified Schedule in Primavera


Review Modified Design in 4D Viewer

4D Model Taken at 3/25/2001 From 4DViewer


Review Modified Schedule in Microsoft Project


Review Changed Activities in Desktop Browser

Actual Change

Affected

Activities


Review Modified Schedule in Excel

Actual Change

Documents

Stanford Universityeil.stanford.edu/ficas/FICAS032703.pdf · Primavera P3 Vite MS Project 4D Viewer ... notification_svc = SETUP ... 30 Stanford University Event Dependency Graph