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LIS 1311 Fall 2004: Lecture 5 a Classification Of IT Applications
Outline 1. Programs, Systems & Applications 2. Application Coverage 3. Classification Of IT Applications • By System Architecture • By Scope or Degree of Integration • By Functional Or Industry Domain • By Functional Level • By Content Type • By Computational Focus 4. Trends
Programs, Systems & Applications • A program is a sequence of instructions which can be executed by a computer to accomplish some function. • An information system is a set of processes, information stores and information flows, manual or computerized, which are intended to perform an integrated function. • An information technology application (often called a “software system” or “automated system”) is a set of programs, files and/or database(s), which are intended to perform an integrated function as an information system or part of a larger information system.
Application Coverage 1. Most companies move and process a lot of information; that is, they are to some extent information systems: • in a manufacturing company ~30%of the staff time is devoted to information processing; • in a bank or insurance company ~90+%of the staff time is devoted to information processing; 2. To the extent that an ‘information worker’s’ tasks are repetitive, rule-based and ‘algorithmic’ they can be captured in software and done by a computer. Conversely, to the extent that these tasks involve the recognition of novelty, inter-personal negotiation, creative problem solving, and decision making under uncertainty, they cannot be entirely delegated to software.
Systems Architecture: Generations • First Generation Early Computing (40’s 50’s) Centralized, Batch Processing Systems – • Second & Third Generation-Mainframe computing (60’s-70’s): – – • Networked terminals transistors (second) integrated circuits (third generation) Fourth Generation: Personal computing, local and remote networks. – LAN’s extended to constitute the Internet
Systems Architecture: Generations • Fifth Generation: – The PC is replaced by portable devices and information appliances, that have less computing power, but that are cheaper and easier to use. – Servers use Web Services, exchanging & operating on messages containing either document-oriented or procedure-oriented information. Note: the diagrams shown here are not network configurations (e. g. star, token ring), but more general architectures. All LANs today are use a star configuration, including WIFI LANs.
5 th Generation: Web Services? • Web service is a software system designed to support interoperable machine-to-machine interaction over a network. • Uses HTTP to transmit both information and commands, encoded in XML • Disadvantage: HTTP is stateless. • Discussion?
Web Services, con’t • SOAP: basic messaging framework using XML and HTTP • WSDL Web Services Description Language: describes the public interface of the service • UDDI: Universal Description, Discovery, and Integration: A platform-independent, XMLbased registry for businesses worldwide to list themselves on the Internet
Current: 3 -Tier Web Architecture 1. Database Tier: relational database MSAccess, My. SQL, Oracle, SQL Server; located on a SERVER. 2. Middle Tier: software that makes the database securely available on the Web ODBC: Open Data. Base Connect & one of: – php (); ASP (active server pages); ZOPE; Cold Fusion, etc. 3. Client Tier: Browser Data is passed back and forth between these tiers or components, basically in the form of search requests and results.
Scope/Degree Of Integration Classification 1. Individual Use Systems • Personal productivity (e. g. Word, Excel, etc. ) • Specialist productivity (e. g. engineering, software, etc. ) 2. Departmental Systems • Productivity and shared information for a department • Often single applications for one department, accessed by other departments (e. g. HR) e. g. registration system, library system, course management system 3. Enterprise Systems • Productivity and shared information across many departments in an entire (perhaps world-wide) organization (e. g. order-inventory-production-purchasing) e. g. integrated “Web portal, ” “My U of T”
Sidebar on Integration In the 1970’s it was thought possible for an organization to design and build fully integrated information systems around one or more conceptually integrated databases. The technology of the time could not support this: - expensive hardware, limited capacity - limited ability to design and build integrated systems - limited understanding of how to design for change Also, organizations aren’t strictly hierarchical and don’t behave in logically integrated ways, and they change rapidly. Therefore, numerous, more or less independent systems grew up in most organizations dealing providing separate applications to different functional areas or process chains. These were often ill-coordinated, and built with a focus on software requirements not the overall needs of the organization.
Sidebar on Integration Hence, Enterprise Application Integration (EAI) • focus on integrating existing information systems within a business. • main tasks: linking dissimilar software systems and providing a seamless electronic end-to-end information flow. • technology involves ‘standard’ object-oriented representations of business processes to serve as the ‘glue’. These objects are tailored to the specific needs and existing systems of each business. • API’s: Application Program Interface: is a set of definitions of the ways one piece of computer software communicates with another. • XML (e. Xtensible Markup Language) is becoming an important tool in this effort.
Scope/Degree Of Integration Classification 1. Workflow Systems • Rule based automated movement of information from one department/system to another 2. Workgroup/Collaboration systems • Shared information and scheduling for an ad hoc group 3. Integrated Enterprise Systems • Productivity and shared information across an entire (perhaps world-wide) organization 4. Multi-Enterprise Integration • Productivity and shared information with business partners
Sidebar on Integration The Enterprise Information Portal (EIP) • focus on providing a common access point (from the web) to all products and services offered by a company. • main tasks: enabling business partners, potential clients, the media, or anybody at all, to access all information about an organization and to transact business through a common, always up-to-date, easy-to-use, secure gateway. • Technology • front-end web servers, linked to all ‘back-end’ systems. • Information taxonomy generation and search aids • Uses: everything Will everything look like a browser? Does this sound too good to be true? It was!
Organizational Level Classification 1. Operational (productive) - Record Keeping, Transaction Processing (TP/OLTP) - Process Control
Transaction Processing Systems • focus on timeliness and speed of response • main tasks: transaction recording, response and reporting (inquiry) in real-time • Technology • on-line transaction processing (OLTP) • requires database and telecommunications • Uses: • Automated Banking Machines (ABMs) • airline reservations • library circulation control • order processing • shipment tracking systems
Sidebar on Entity Identification The physical entities about which an application maintains information must be identified to it when an interaction concerning them takes place. A regular user can be given a logon ID and password, but casual users and things need other means of identification, such as: 1. Magnetic stripe cards 2. Barcodes 3. Radio Frequency ID (RFID)
Organizational Level Classification 3. Knowledge Work (connective) - Word Processing, Spreadsheets, Presentations - Project Management - Document Management, Information Retrieval (IR)
Organizational Level Classification 2. Management (responsive) - Management Information Systems (MIS) - Enterprise Resource Planning (ERP) - Data Mining and Decision Support Systems
Decision Support Systems (DSS) • focus on analysis and understanding of process, and anticipating change or the results of change • main tasks: providing access to historical data in ad hoc ways and the ability to model situations to answer ‘what if’ type questions using real data. Technology: • On-line Analytical Processing (OLAP) • requires integrated databases with flexible views, modeling and simulation tools and fast machines Uses: • marketing (target the ‘best’ customers) • inventory, pricing and location planning • stocks and bonds trading
Organizational Level Classification 1. Executive/ Strategic (adaptive) - Executive Support Systems - Business Intelligence Systems - Dynamic Modeling
Functional/Industry Domain Classification 1. Within The Enterprise • Finance/Accounting • Production/Supply • Inventory/Distribution • Sales/Marketing • HR • etc. 2. By Industry • Finance/Banking • Insurance • Manufacturing • Retail • Library • Government • etc
Content Classification 1. Structured ‘Atomic’ Data, e. g. • Record Keeping/TP/MIS Systems 2. Unstructured Text, e. g. • Document Management Systems • Web Content Management Systems • Information Retrieval Systems 3. Multi Media, e. g. • Photo/Music Library Systems 4. Digital ‘Models’, e. g. • Geographic Information Systems (GIS): A Model of ‘Things in Space; ’ CAD The open problem is integrating functionality across content of different types.
Computational Focus Classification 1. Procedural/Rules Driven 2. Statistical Analysis 3. Dynamic Modeling 4. Reasoning/Artificial Intelligence (is this different from #1 ? )
TRENDS Applications are becoming: 1. More distributed 2. More mobile 3. More interconnected