Class 7 Distributing Business and Systems Asper School of Business - MBA Program 6150 Management of Information Systems & Technology April-June 2009 Instructor: Bob Travica Updated May 2009

Outline Strategies of Distributing Business & Systems Concept of Distributed Systems Client-Server Architecture 2 of Management of Information Systems & Technology Messages for change leadership

Strategies of Distributing Business & Systems Dispersed org. entities can have different information needs – lowhigh Spatial dispersion Manufacturer for local market and exports (sourcing & production vs. marketing & sales) Fast food franchiser (McDonald’s; finances vs. sourcing, HR, sales) Multinational Manufacturer (Ford; global sourcing, international R+D, production, marketing…) Organizations dispersed in space (individuals, groups, units; e.g., salespeople in master case) 3 of Management of Information Systems & Technology Information systems have to support different strategies of distributing business Inter-cultural aspect (master case)

Application Software (Functionality, Data processing) Application Software (Functionality, Data processing) Data (Data mgmt, Database) Data (Data mgmt, Database) User Interface (Presentation, input/output screens) User Interface (Presentation, input/output screens) Information System Parts (resources, services) Distributed Systems Concept: What Can Be Distributed More 4 of Management of Information Systems & Technology Any of these parts can be distributed – data, functionality, user interface. If all run by one computer, the system is centralized. An aspect of systems architecture (overall design of computing resources).

Distributed Systems: Data View Method 1: Central store, distributed access. Role of networks (3i, Northwest Airlines). 5 of 12 Rule #1 for distributed systems: Make data available where users need them. Method 2: Partition data store. Data fed and searched locally; occasional cross search. More TorontoVancouver Winnipeg Purchasing ProductionSales

Golden rule: Regardless of the specific architecture, users should not care if a system is distributed and in what manner. Access should be seamless. Method 3: Data partitions stored locally in real time, and partitions replicated across locations in certain intervals. 6 of 12 Purchasing Production Sales Purchasing Production Sales Purchasing Production Sales TorontoVancouver Winnipeg

Computer networks – key role in distributed systems. Networks are part of IT Infrastructure (foundational systems serving entire enterprise). Mainframe with dumb terminals in departments Departmental stand-alone systems Client-Server Systems in/across departments CentralizedDecentralized Data processing, data storage, user interface – a continuum showing levels of distribution of system parts in an enterprise: 7 of Management of Information Systems & Technology Distributed Systems Continuum

Client-Server (C/S) Architecture Most frequent today C/S systems distribute data, functionality or both between a machine that requests a service (client) and a machine that provides a service (server). ClientServer Request Service More 8 of Management of Information Systems & Technology Division of responsibilities for data and functions, user interface usually on the client.

Models of C/S architecture determined by different patterns of sharing responsibility for data, functionality, and user interface between computers. Models of Client-Server Architecture Shared Processing (both server and client have certain functionality; LAN w/ database server, Internet models – applets, Web services) More 9 of 12 Client - Input/Output screens - Query and Report code Report creation Request Report Data lookup, input Data table transfer Note: Server is software, but it usually runs on a dedicated computer. - Database (data) - Query and Report processing … Database Sever

Variant of Shared Processing with middleware * Example from HR domain: An employee is defined by an employee number, name, job position…, is associated with 1 department, reports to 1 manager, cannot have $0 salary, can have different benefit packages over time, etc. Middleware Database Server (Databases can be on a mainframe - “legacy system”) (Code defining rules of business*; translation software) Client (Application software) More 10 of Management of Information Systems & Technology

Variant of Shared Processing via the Internet (applets; Web services) Cases: SABRE More 11 of Management of Information Systems & Technology - Upon getting data & applet, runs if-then calculations Web Server Application Server Other systems Mortgage Info Request Customer data Customer Data + Mortgage Applet Client Internet Database Server Request translated Request translated Web page Web page with cust. data + applet Case: Chubb & Son

12 of Management of Information Systems & Technology Messages for Change Leadership If business is to get distributed, determine how can IS support this strategy. Be sensitive to company’s culture regarding its readiness for distributed systems (trust issues). Beware that data must be available where users need them, and that users should not worry whether the system is distributed or not.