1. Types of Application Integration
IST 421
Spring 2004
Lecture 2

2. Enterprise integration should enable organizations to become more agile and flexible. This means:
Continuously monitor market demand
Quickly respond by providing new products, services & information
Quickly introduce new technologies
Quickly modify business methods
Lee, Siau, & Hong, Enterprise Integration with ERP and EAI, Communications
Of the ACM, Vol. 46, Number 2, February 2003,

3. Data-Level Integration

4. Data-Level Integration
Advantages:
Tools and techniques currently exist
Relatively easy
Requires no changes to the application logic or database structure

5. Coupling The act of bringing together Binding logic with data
Problems:
Creates one application and database out of many, each dependent on the other
Over time, a change to any system means a change to the coupled systems as well

6. Cohesion Act of “sticking” together
Applications and databases are independent
Changes to any source system should not affect the others
Integration solutions should be cohesive rather than coupled

7. Coupling vs. Cohesion
Systems can be added, changed or removed from a cohesive solution
Message brokers provide this infrastructure
For common business processes to be reused, coupling may be more valuable
Distributed objects
Transaction processing monitors
Application servers

8. Data-Level Example
A company that manufactures copper wiring would like to hook up the inventory control system, a client/server system using PowerBuilder and Oracle, and the Enterprise Resource Planning (ERP) system using an Informix relational database.

9. Data-Level Example Only sales data will move
When a sale is entered into the inventory control system, copy the new information to the ERP system to ensure availability of raw material.
Frequency of data movement – real time
Choose method for moving data

10. Data-Level Example Replication and Transformation Solution
Move information between different types of databases, i.e., Sybase, Oracle, Informix
Move information between different models, i.e., relational, object-oriented, multidimensional
Transforms data on the fly
Transform
09/17/62
Linthicum
Dave
September 17, 1962
David Linthicum

11. Data-Level Integration
Database-to-Database
Replication solution – move data between databases with the same basic schema
Replication and Transformation solution
Advantages:
Simple
Low risk
Reduces cost
Problems:
Application logic may be bound to the data, i.e., SAP R/3.

12. Data-Level Integration
Federated Database
“Virtual” Database
Single point of application integration
Access data from any number of databases, using various brands, models, and schemas

13. Data-Level Integration
Advantages:
Middleware to share information between applications
Hides the difference in the integrated databases
Problems:
Need to create logic for integrating the applications with the database
Not considered a true integration approach

14. Data Source to Consider
Relational databases
IDMS
IMS
VSAM
ISAM
Flat files

15. Application Interface Level

16. Application Interface Level
Application Interfaces – gain access to levels or services of an application
Application Programming Interfaces (APIs) –well-defined mechanisms to connect to resources such as an application server, middleware layer, or database.

17. Application Interface Level
Java’s RMI (Remote Method Invocation)
CORBA (Common Object Request Broker Architecture)
IIOP (Internet Inter-ORB Protocol)
Microsoft’s COM+ (Component Object Model)

18. Application Interface Level Example
A company has 2 systems: a new ERP system and a custom COBOL system. Each system runs on its own processor, connected to the corporate network.

19. Application Interface Level Example
ERP vendor provides APIs that work within C++, C, and Java.
Libraries that drive the API downloadable from vendor’s web site.

20. Application Interface Level Example
GetInvoiceInformation(“12345”);
<BOM>
John Smith
222 Main Street
Smalltown, VA
Invoice Number:
001 Red Bricks
<EOM>

21. Application Interface Level Example
GetCustomerInformation(“cust_no”);
QuantityAvailable(“product_no”);

22. Application Interface Level Example
COBOL system, no API exists.
Build an API – expensive
Select the right middleware to bind the the ERP API on one side and the custom application API on the other side.
Message brokers
Message-queuing middleware
Application servers
Interfaces in this example provide access to both data and business processes

23. Packaged Applications
SAP, PeopleSoft, Oracle, Baan
Business critical applications
Accounting
Inventory
Human resources
Manufacturing

24. Packaged Applications
Centralized Architecture

25. Packaged Applications
Two-Tier Architecture – 3 distinct layers
The user interface layer
The business logic layer
The data layer
Fat Client

26. Packaged Applications
Two-Tier Architecture – 3 distinct layers
The user interface layer
The business logic layer
The data layer
Thin Client

27. Packaged Applications
Three-Tier Architecture
Most popular
Scalable

28. Application Interface Level
Architecture has direct relationship with application interfaces
Many packaged applications allow direct access to the database by using the business logic or application layer
Understanding the architecture presents the opportunities for integration

29. Packaged Application APIs
Types of services
Business service – interfaces to any piece of business logic within the application; provide integrity controls for the data
Example:
Update the database with new customer information from another application, business services would allow you to invoke the “customer update business service” from the API

30. Packaged Application APIs
Types of services
Data service – direct route to the logical or physical database; generally for exporting data
Objects – data and business services bound as objects; offer an advantage of maintaining integrity checks set up by the packaged applications

31. Vertical Market APIs Provide access to industry-specific applications
SWIFT (Society for Worldwide Interbank Financial Telecommunications)
Messaging standard
Owned by member banks, including the central banks of most countries

32. Vertical Market APIs FIX (Financial Information Exchange)
Messaging service for real-time electronic exchange of securities transactions
Evolved FIXML to give structure and valid grammar using XML to standard messages
HL7 (Health Level 7)
Standard for electronic data exchange of health care information

33. Method-Level Integration

34. Method-Level Integration
Allows the enterprise to integrate through sharing common business logic or methods.
Define methods that can be shared by multiple applications - reused
Infrastructure for method sharing needed

35. Method-Level Integration
Requires most applications be changed in order to take advantage of method sharing
Change application
Test the changed application
Integrate
Redeploy the application
$$$$$

36. Method-Level Integration Example
Two Applications:
C++ application running on Linux
Client/server Java application on NT with Sybase database
Applications need to be tightly coupled to share business logic - Composite Application

37. Method-Level Integration Example
Rebuild the applications in one of two ways:
Move business logic to shared server
Rebuild each application using method-sharing mechanism
Distributed object technology which allows remote sharing of methods:
CORBA
COM+
Work intensive process!!

38. Method-Level Integration
Four types of processes:
Rules – set of conditions that have been agreed upon. Rules are built into applications to control the flow of information.
Example: travel reimbursement requests must be made within 30 days of returning from a trip

39. Method-Level Integration
Logic – sequence of instructions in a program
Example: if button is pushed, then screen pops up
3 Classes of Logic:
Sequential processing
Selection
Iteration

40. Method-Level Integration
Data – sharing information between applications, computers or humans
Objects – bundles of data encapsulated inside an object and surrounded by methods that act upon the data
C++
Java

41. Method-Level Integration
Frameworks – abstract classes and their object collaboration. Object-oriented programming supports software reuse, frameworks support design reuse.
Fully debugged and tested software subsystems
Centrally located and accessible by many applications
Provide infrastructure for sharing methods – provide objects that are accessible by a number of applications
Provide reuse throughout an industry where many processes are the same

42. Enabling Technology
Application or Transaction Servers – transaction processing monitors for high volume systems
WebLogic
Kiva (Netscape Application Server)
Net Dynamics

43. Enabling Technology Distributed Objects Component Object Model (COM+)
Common Object Request Broker Architecture (CORBA)

44. Limits on adoption of this Technology
Political reasons are a primary reason for limited adoption of this technology
Internal politics
Inability to select a consistent technology set
Most invasive level of B2B integration