ERP Course: Enterprise Application Integration Readings: Chapter 3 from Gustavo Alonso et al Peter Dolog dolog [at] cs [dot] aau [dot] dk E2-201 Information

ERP Course: Enterprise Application IntegrationReadings: Chapter 3 from Gustavo Alonso et al

Peter Dologdolog [at] cs [dot] aau [dot] dkE2-201Information SystemsNovember 15, 2006

2Peter Dolog, ERP Course, EAI

quotationsupplier andcustomer mgmt

order processing procurement shipment

management financial

Copyright Springer Verlag Berlin Heidelberg 2004

IS/ERP IS/ERP IS/ERP IS/ERP IS/ERP


Historical Perspective

presentation layer

resource management

layer

application logic layer

client

info

rmat i

on

syste

m

1. define access channelsand client platforms

2. define presentation formats and protocols forthe selected clients andprotocols

3. define the functionalitynecessary to deliver thecontents and formats neededat the presentation layer

4. define the data sourcesand data organization neededto implement the applicationlogic

top-down design



clientpresentatio

n layer

resource management

layer


info

rmat i

on

syste

m

3-tier architecture

middleware



client

resource management

layer


info

rmat i

on

syste

m

N-tier architecture

middleware

presentationlayer

Web server

Web browser

HTML filter



request

response

invokingexecution thread

invokedexecution thread

blo

ckin

g

peri

od


Blocking/Synchronous Communication


Nonblocking/Asynchronous Communication

put

put

invokingexecution thread

invokedexecution thread

queue

fetch

fetch

queue

thre

ad

rem

ain

sacti

ve



RPC Abstraction

Remote Procedure Call

sockets

TCP, UDP

Internet Protocol (IP)

Remote Procedure Call: hides communication details behinda procedure call and helps bridge heterogeneous platformssockets: operating system level interface to theunderlying communication protocolsTCP, UDP:User Datagram Protocol (UDP) transports data packets without guaranteesTransmission Control Protocol (TCP)verifies correct delivery of data streams

Internet Protocol (IP):moves a packet of data from one node to another



RPC

communicationmodule

client

procedure call

client stubbindmarshalserializesend

client proces

s

communicationmodule

server

procedure

server stub

unmarshaldeserializereceive

server process

dispatcher(selectstub)



client 1. BOT 4. procedure call 10. EOT

client stub 2.register txn & create context 5.add txn id & context to call 11.request commit

14.confirm termination

client process server

9. procedure

server stub6. extract context and txn id7. register server for txn13. participate in 2PC

server process

transaction manager

3. create txn idregister txnregister client for txnreturn txn id

8. lookup txn idregister server for txn

12. lookup txn idrun 2PCnotify client of outcome



Other Middleware

Object brokersObject monitorsMessage-oriented middlewareMessage brokers


external application

external application

Input queue

Input queue

Output queue

Output queue

Reliablequeuingsystem

RequestQuote

SupportQuote

Copyright Gustavo Alonso, ETH


dispatcherinventory manage

mentERP

shipping

message-oriented middleware

month-end

closing

new PO

new PO

new PO

new PO



message broker core

sender receiver

message broker

with message brokers, custom message routing logic can be defined at the message broker level or at the queue level

in basic MOM it is the sender who specifies the identity of the receivers



dispatcher(publisher)

inventory manage

ment(subscrib

er)

ERP(subscrib

er)

shipping(subscri

ber)

message broker

month-end

closing(subscri

ber)new PO

new PO

new PO

new PO

new PO



admin

message broker MB-A

message broker MB-B

client

client

…

admin

client

client

…

admin

message broker MB-C

client

client

…

administrative domain A

administrative domain B

administrative domain C



DBMS applications

message broker

SmartQuotationadapter

e-mailadapter

databaseadapter

SmartQuotation

SmartForecastingadapter

SmartForecasting

XYZadapter

XYZ

integrating application (contains the composition

logic)



message broker

SmartQuotationadapter

SmartQuotation

SmartForecastingadapter

SmartForecasting

RFQ processing

1A 6

B C 72 4

3

5

8

at systems startup time (can occur in any order, but all must occur before RFQs are executed)

A: subscription to message quote

B: subscription to message quoteRequest

C: subscription to message newQuote

at run time: processing of a request for quote.

1: publication of a quoteRequest message

2: delivery of message quoteRequest

3: synchronous invocation of the getQuote function

4: publication of a quote message

5: delivery of message quote

6: publication of a newQuote message

7: delivery of message newQuote

8: invocation of the createForecastEntry procedure



check if offered product

check if worth proceeding

get quote from quotation system

get quote from supplier

enter quotein forecasting system

send quote to customer

ContractExists=true

ContractExists=false

Offered=true

Offered=false

GoAhead=true

update quotation system

variables: QuoteReferenceNumber: int Customer: String Item: String Quantity: int RequestedDeliveryDate: Date DeliveryAddress: String GoAhead: Bool ContractExists: Bool Offered: Bool

else



workflow engine

resource broker

completed work items

inbound queue

resource 1

resource 2

resource n

1

2

4 53

workflow definitionsoutbound queues

workflow designer



Copyright Gustavo Alonso, ETH

Documents

ERP Course: Enterprise Application Integration Readings: Chapter 3 from Gustavo Alonso et al Peter Dolog dolog [at] cs [dot] aau [dot] dk E2-201 Information