3- Tier Client/Server

1. 이 프레젠테이션에는 수행 항목을 만드는 청중 토론이 포함되어 있습니다. 프레젠테이션하는 동안 PowerPoint를 사용하여 수행 항목을 확인합니다. • 슬라이드 쇼에서 마우스 오른쪽 단추를 누릅니다. • “회의록 작성”을 선택합니다. • “수행 항목” 탭을 선택합니다. • 제안되는 대로 수행 항목을 입력합니다. • 이 상자를 없애려면 “확인”을 누릅니다. • 프레젠테이션 끝에 요점을 입력한 수행 항목 슬라이드를 자동으로 만들어 줍니다. 3-Tier Client/Server [OOPSLA 연구실] [민 경 섭]

2. 이 프레젠테이션에는 수행 항목을 만드는 청중 토론이 포함되어 있습니다. 프레젠테이션하는 동안 PowerPoint를 사용하여 수행 항목을 확인합니다. • 슬라이드 쇼에서 마우스 오른쪽 단추를 누릅니다. • “회의록 작성”을 선택합니다. • “수행 항목” 탭을 선택합니다. • 제안되는 대로 수행 항목을 입력합니다. • 이 상자를 없애려면 “확인”을 누릅니다. • 프레젠테이션 끝에 요점을 입력한 수행 항목 슬라이드를 자동으로 만들어 줍니다. Case Study 1: U.K. Employment Service Rolls Out 3-Tier in Record Time [OOPSLA 연구실] [민 경 섭]

3. Table of Contents • Background • The Application • 3-Tier Architecture • Advice

4. Background The U.K. government passed the Job Seekers Allowance legislation to encourage people to get jobs and move off benefit payments faster. To comply with this new program, the Employment Service’s staff quickly needed a top-notch application. They were new required to monitor the progress that 2.45 million unemployed people were making toward finding work. The IT department at Employment Service rose to this mammoth challenge. It rolled out a major new application - called the Labour Market System - in record time. It’s one of the largest operational client/server systems in the world.

5. The Application : Requirements Employment Service is an executive agency of the Department for Education and Employment in the U.K. Its branch offices are located throughout England, Scotland, and Wales. The agency’smain business is to help people without jobs find work. Currentlyabout 2.45 million people have registered as being unemployed.Before the government passed the Job Seekers Allowance(JSA)legislation, unemployed people received benefit payments if theyhad previously made unemployment insurance payments, or ifthey requested income support. JSA added additional requirements.To keep receiving benefit payments, Employment Services clientshave to sign and comply with a Job Seekers Agreement. This agreementmakes them promise to apply for a certain number of jobs within a particular time period. Staff members at the employment offices haveto log their client’s Job Seekers Agreement and job-seeking activities.As a last resort, they can recommend that benefits payments be dockedif clients aren’t making progress.

6. The Application : Existing Systems • OSCAR • log the meetings between the employment office staff and the people coming in to seek jobs • have its own data locally • SVACS • show the vacancies available for jobs in the U.K. • have data in nine relational database • The Benefits Payment System • track payments of unemployment benefits and allowances

7. The Application : New System • Labor Market System(LMS) • N-tier client/server application • combine OSCAR and SVACS’s local information into global databases • Job Seekers Agreement Payment system(JSAP) • extend ‘the Benefits Payment System’ • users can access it through the LMS PCs

8. Architecture • Physical architecture • LMS server, JSA server, many LMS PCs, JSA Payment System, LMS Database Centers, dedicated 64Kbps WAN, etc • Logical architecture • tier 1 • the client s/w and Tuxedo /WS running on the PCs in the employment offices • tier 2 • multiple LMS servers that run Tuxedo services • tier 3 • four regional Ingres database

9. Physical architecture

10. Logical architecture

11. Advice • Use UNIX multiprocessors so you can inexpensively increase processing power in small increments as you need it • A TP Monitor is essential when dealing with many client connections • Test, test, test at all stages of development • Plan for the challenges of distributing s/w remotely to a large number of users • Recognize that users will need on-going training and mentoring to exploit a new system’s fill capabilities

12. 이 프레젠테이션에는 수행 항목을 만드는 청중 토론이 포함되어 있습니다. 프레젠테이션하는 동안 PowerPoint를 사용하여 수행 항목을 확인합니다. • 슬라이드 쇼에서 마우스 오른쪽 단추를 누릅니다. • “회의록 작성”을 선택합니다. • “수행 항목” 탭을 선택합니다. • 제안되는 대로 수행 항목을 입력합니다. • 이 상자를 없애려면 “확인”을 누릅니다. • 프레젠테이션 끝에 요점을 입력한 수행 항목 슬라이드를 자동으로 만들어 줍니다. Case Study 2: PeopleSoft Moves Applications to 3-Tier [OOPSLA 연구실] [민 경 섭]

13. Table of Contents • Background • The Application • 3-Tier Architecture • Advice

14. Background With revenues of $450 million in 1996, PeopleSoft has built a successful business delivering 2-tier client/server applications that run their customers’ core business functions. While these are enterprise-class applications - mostly used by Global 2000 customers - they are typically installed as departmental applications that support a few hundred concurrent users. But PeopleSoft recognized that its customers were changing the way they were using their applications. With the arrival of the Internet, many of PeopleSoft’s customers began launching initiatives to let all their employees access the applications. In addition, many of these customers were using several PeopleSoft applications together

15. The Application : Requirements Instead of a few hundred users in a department accessing a particularapplication, tens of thousands of concurrent users will be using an entiresuite of applications.PeopleSoft must provides a series of integrated modules that run its customers’ core business functions. These applications will be used by Global 2000 customers that are eighty percent of PeopleSoft customers. And remaining small business, higher education institutions, and federal, state, and logical governments in US and Canada will use them.PeopleSoft have to improve performance, expand scalability, and increase the interoperability between its applications.

16. Architecture • Physical architecture • Tuxedo application server with EventBroker, Back-end Database, remote call over WAN • Logical architecture • tier 1 • PCs running the PeopleSoft client application, Tuxedo /WS, and Jolt • tier 2 • application servers running Tuxedo services • tier 3 • broad range of databases, including Informix, Oracle, MS-SQL server, Sybase, DB2

17. Physical architecture

18. Logical Architecture

19. Advice • Keep it simple, stupid • Clearly define your goals at project start. Make sure you get extensive feedback from customers • Adopt a gradual strategy for moving to a 3-tier environment • Understand what’s flowing back and forth on the network to make the right choices in separating client and server functionality • Take advantage of third-party products. There’s no need to spend time developing a component if someone else has one that does the job

20. 이 프레젠테이션에는 수행 항목을 만드는 청중 토론이 포함되어 있습니다. 프레젠테이션하는 동안 PowerPoint를 사용하여 수행 항목을 확인합니다. • 슬라이드 쇼에서 마우스 오른쪽 단추를 누릅니다. • “회의록 작성”을 선택합니다. • “수행 항목” 탭을 선택합니다. • 제안되는 대로 수행 항목을 입력합니다. • 이 상자를 없애려면 “확인”을 누릅니다. • 프레젠테이션 끝에 요점을 입력한 수행 항목 슬라이드를 자동으로 만들어 줍니다. Case Study 3: Wells Fargo Leads the Way to Internet Banking [OOPSLA 연구실] [민 경 섭]

21. Table of Contents • Background • The Application • 3-Tier Architecture • Advice

22. Background It was once simple to understand the difference between a bank, a brokerage house, a mutual fund company, and an insurance company. They offered fundamental products, and there was little overlap. Today, the differences have become blurred as financial institutions of all types compete for investors’ funds. Leadership in the financial services industry now requires that an organization be able to quickly adapt to a changing market, offering new products and services to its customers in a timely and efficient manner. Wells Fargo Bank has become a technology leader in banking, thanks in part to its pioneering use of distributed object computing technology. This technology has helped the company achieve several business objectives, including changing the way bank employees work with computers to become customer-focused rather than account-focused Innovations made possible through the use of this technology also enabled Wells Fargo to become the first major bank to offer its customers secure on-line access to account balances through the World Wide Web.

23. The Application : Requirements In the 1980s, competition for investors’ funds - traditionally kept in banks - expanded to include brokerage and insurance companies. To remain competitive, banks began offering products such as mutual funds and brokerage accounts - products historically outside the purview of traditional banking. By the late 1980s, a growing trend wad compound statement banking, where customers expected to receive a single, unified statement listing the balances and transactions for all of their accounts - including checking and savings, mortgage, credit card, brokerage, and retirement accounts. Customers wanted their banking activities to be structured in terms of their overall relationship with the bank instead of a single account.

24. The Application : Existing Systems • Direct deposit accounts in mainframe • Mutual funds in Digital VAX/VMS system • Brokerage account processing in Tandem How can we combine all these information seamlessly and correctly ?

25. The Application : New System • Customer Relationship System(CRS) • use BEA’s ORB, ObjectBroker • customers can retrieve overall relationship with the bank, including all accounts owned and their balances and statues by using SSN or EIN • Applications • Wells Fargo’s Internet Banking Solution • Interactive Voice Response Unit(IVRU) • Automated Teller Machine(ATM) • A Stock market data application

26. Architecture • Physical architecture • Back-end mainframe application servers, Middle-tier ObjectBroker, client PCs • Logical architecture • tier 1 • windows-based client application to provide GUI • tier 2 • Digital’s ObjectBroker using CORBA object model • tier 3 • several legacy application systems

27. Interactive Voice Response Unit Client PC (Windows) ObjectBroker ObjectBroker Sun (SunOS) HP 9000 (HP-UX) ObjectBroker ObjectBroker ObjectBroker IBM(MVS) IBM(MVS) IBM(MVS) Digital (VAX/VMS) HP 9000 (HP-UX)

28. Product Customer Account Service Deposit Bill Pay Service Container Account On-line Service Credit Uses Business Object Model

29. Advice • Transform your organization into a group that can effectively develop component-based, • Include users and business participants in the design and development processes • Understand the business process - both the existing and the desired one • Invest time and energy in developing an object model that truly represents the business process • Provide sufficient funding to maintain and enhance your object model

30. 이 프레젠테이션에는 수행 항목을 만드는 청중 토론이 포함되어 있습니다. 프레젠테이션하는 동안 PowerPoint를 사용하여 수행 항목을 확인합니다. • 슬라이드 쇼에서 마우스 오른쪽 단추를 누릅니다. • “회의록 작성”을 선택합니다. • “수행 항목” 탭을 선택합니다. • 제안되는 대로 수행 항목을 입력합니다. • 이 상자를 없애려면 “확인”을 누릅니다. • 프레젠테이션 끝에 요점을 입력한 수행 항목 슬라이드를 자동으로 만들어 줍니다. Case Study 4: Apple Improves Ordering With 3-Tier Upgrade [OOPSLA 연구실] [민 경 섭]

31. Table of Contents • Background • The Application • 3-Tier Architecture • Advice

32. Background Apple computer relies on its electronic ordering systems to give its authorized resellers and service providers an easy way to order computers and parts. This lets the resellers have greater control over the ordering process, and it offers Apple cost savings by minimizing administrative tasks. But when Apple decided to move to an SAP-based solution for all its corporate functions, it found that it also had to replace the existing ordering systems with a new one that could interoperate with SAP R/3. To accomplish this, Apple developed a new worldwide ordering system based on a 3-tier architecture. The new system - called AppleOrder Global - serves as a font-end to SAP for processing electronic orders. It provides the scalable, on-line performance needed to service thousands of resellers around the world. AppleOrder Global is now up and running in Canada and Europe; U.S. resellers are due to come on-line in 1998.

33. The Application : Requirements To develop and roll out an electronic ordering system that would garner internal acclaim - at least from Apple’s resellers - we need as follows.First, to develop a scalable system with interactive interfaces.Next, to support an international production environment. That is, we must provide real-time performance on a global scale.Last, to ensure that all the functionality of existing systems are offered.

34. The Application • Existing system • five different electronic ordering systems in different regions around the world • New system • AppleOrder Global • electronic ordering system • use SAP R/3 modules • users can get information about the status of pending orders and shipments and access their account and invoice information and up-to-date product and pricing information. etc…

35. Architecture • Physical architecture • Macintosh computers, Leased line, AppleOrder Global RS/6000 application server, SAP RS/6000 Order management server • Logical architecture • tier 1 • AppleOrder Global GUI and Tuxedo /WS • tier 2 • AppleOrder Global application server • tier 3 • SAP R/3 Order Management application server

36. Dedicated Network AppleOrder Global RS/6000 Application Server Reseller’s Macintosh SAP RS/6000 Order Management Server T1 Line Dial-up or Leased-line Connection Reseller’s Macintosh RFCs over High-speed LAN Physical Architecture

37. Tier 3 Order Management Server (acting as SAP client) Tier 1 Client Tier 2 Application Server AppleOrder Global GUI MacApp Framework Application Objects Custom Order Management ABAP/4 Routines SAP R/3 Application Order Management API Application Layer API AppleOrder Global API Local Data API SAP API Application Objects Order Management API Middleware API Remote Function Calls Loca Data API AppleOrder Global API CTree Database Middleware API Tuxedo Workstation Handler Oracle Remote Function Calls Tuxedo /WS Logical architecture

38. Advice • Take time in designing the system. Once you begin development, it’s hard to go back and revise the design • Make sure you have a specialist in each technology • Be sure to have people from the business side of the house participate as you design and develop the system • If possible, reuse work you’ve already completed