Evolution of Information Technology Infrastructure BA 572 - Week 1
Definitions u Information Technology (IT) Infrastructure: physical facilities, services and management that support computing resources n Information Technology l Hardware l Software l Database l Telecommunications n IT personnel & Networks
Definitions u Information Systems (IS) Architecture: the “plan” that aligns IT infrastructure with business needs n Help people effectively fulfill their information needs n Note that the term “Information Architecture” is now being used to describe process of designing web sites
Performance Metrics “ROI” u How does IT add value? u What is purpose of IT applications? n Automate n Facilitate/Informate n Enable
Adapted from "Intranets and Middleware", HBR 397 -118.
Evolution of Information Technology Infrastructure Web Services Distributed db Client/Server db db db PC/LAN Mainframe db db
Mainframe Data Processing Era u IT Infrastructure (host-centric processing) n Hardware: Mainframe with text-based terminals n Software: Independent functional applications l Served n Data one purpose Storage: independent “files” for each functional application n Telecommunications: Limited support of distributed operations n IT Personnel: technically oriented
Mainframe IS Architecture: Transaction Processing System (TPS) u Emerged n Collect, in the early days of IS store, and process transactions l Source n Perform documents are basis for input routine, repetitive tasks n Found in all functions of an organization n If they fail, the whole organization may suffer n Automate “highly structured” decision processes l Payroll
Mainframe IS Architecture: Management Information System (MIS) u Convert/use TPS data to support monitoring n Alert managers to problems or opportunities n Provide periodic and routine reports l e. g. , summary reports, exception reports, comparison reports n Provide structured information to support decision making l Resulted in “Information overload”
Mainframe IS Architecture: Centralized Corporate Structure Functional Transaction Processing System Management Information System Executive Managerial Purchasing Sales Inbound Raw Production Finished. Outbound Logistics Materials Goods Logistics Operational
PC/LAN Micro-Computing Era u IT Infrastructure (PC environment) n Hardware: PCs (low cost compared to mainframe) n Software: Individual PC applications n Data storage: Individual files linked to apps n Telecommunications: low-speed LANs n IT Personnel: technically oriented & mainframe biased
PC/LAN db db IS Architecture: Decision Support Systems u Proliferation of desktop applications n Why? l TPS/MIS were not providing information needed to support decisions n “End-user” development l Undocumented n Proliferation spreadsheet models of localized data storage
PC/LAN IS Architecture Functional Transaction Processing System Management Information System Executive Desktop Decision Support System Managerial Purchasing Sales Inbound Raw Production Finished. Outbound Logistics Materials Goods Logistics Operational
Client/Server db Client/Server Era u IT Infrastructure (distributed computing environment) Hardware: PCs and Specialized Servers Software: Facilitating Data storage: Distributed Relational database and centralized warehouse n Telecommunications: high-speed LANs n Network: Client/Server n IT Personnel: technically skilled, business oriented n n n u Information n Systems architecture? Share applications and data within and across functional areas
Client/Server db u Facilitating Software Systems Office automation n IT for “office” employees l Document tracking, communication, scheduling, etc.
Client/Server Facilitating Software Systems (cont’d) db n Decision Support Systems l Provide information to support “semi-structured” decision making u Effectiveness n Expert focus Systems l Knowledge-base integrated with DSS l Most are “rule-based” systems that process facts, not numbers u Credit evaluation u Cisco/DELL tech support
Client/Server Database Approaches db u Centralized n All data in one location l Promotes maintenance and security l Subject to single point of failure
Distributed db db Database Approaches db u Distributed data management n Get data closer to applications n Replicated l Complete copies in multiple locations l Significant overhead n Partitioned l Each u Data location has portion of database management becomes an issue l Complex Concurrency Control
Distributed db db db Online Transaction Processing u Transactions used to interact with a relational “client-server” database n For each transaction, OLTP typically deals with a small number of rows from the tables l The transactions are typically highly structured, repetitive and have predetermined outcomes l E. g. , orders, changing customer address, etc.
Client/Server Systems Functional Transaction Processing System Executive db Client/Server System Managerial db Purchasing db db Sales Inbound Raw Production Finished. Outbound Logistics Materials Goods Logistics Operational
Distributed Computing Middleware db db Network Era (Distributed Computing) u IT Infrastructure (distributed computing environment) n Hardware: PCs and high-end Servers n Software: Enabling, enterprise-wide n Data storage: Distributed Relational Database n Telecommunications: high-speed WAN n Network: Middleware n IT Personnel: still technical, but business awareness
Distributed Computing Introduction of Middleware db db u Software that makes it possible for systems on different platforms to communicate with each other. n Allows applications to talk to each other l Consistent Application Program Interface (API) l Code application to talk to middleware, not underlying resources l Upgrade/modify underlying resources without needing to modify applications
Distributed Computing Middleware db db db u ORB db Object Request Broker (ORB) involves synchronous communication and location/platform transparency. u ORB uses object-oriented programming methods.
Distributed Computing ORB (cont’d) Middleware db db db u ORB db architecture: ORB activate service locate service establish connection Client Remote Service communicate
Distributed Computing File Sharing Middleware db db u Napster: ORB activate service locate service establish connection Request Stored Files communicate
Peer-to-Peer File Sharing Distributed Computing Middleware db db db u Kazaa: db Member Request Member Member
Distributed Computing Middleware db db db Advantages of ORB Middleware db u Anonymous interaction among applications n Integrate new client/server applications with existing legacy, mission-critical applications u Easier development environment n Reduce cost n Improve time-to-market of applications u Enables distributed data environment u Enables dynamic web applications
Distributed Computing Middleware db db u Switching n Disadvantages of ORB Middleware costs are high Upgrade from previous “Middleware” solutions u Requires high technical expertise n Tend to outsource n Lengthy deployment time
Distributed Computing Middleware db db db Unresolved Issues with ORB db u Security u Scalability n Related u Rapidly to network capacity changing technologies
Distributed Computing Middleware db db db DBMS Applications db u With advent of high-speed, distributed architectures, expanded our use of database beyond capturing and storing transaction data n Knowledge l Process Discovery of extracting useful knowledge from volumes of data l Supported by: u Massive data collection (Data Warehouse/Data Marts) u Multiprocessor computing u On-line Analytical Processing (OLAP)/Data mining
Distributed Computing Data Warehouse Middleware db db u Collection of data in support of decision making process that is: Subject-oriented: organized by entity, not application n Integrated: stored in one place, even though it originated from a variety of sources n l Crosses functional boundaries of an organization Time-variant: represents a snapshot at one point in time n Nonvolatile: data is read-only n Typically very large n
Distributed Computing Middleware db db db Multidimensional Database db u. OLTP not good when doing analysis of data – poor performance u OLAP – on-line analytical processing
“Slice and Dice” an OLAP Cube
Distributed Computing Advantages of OLAP Middleware db db u All hierarchical or aggregated values can be pre-calculated in the cube rather than accessing the Warehouse n Major u Each n Not reduction in query time cube makes “business sense” normalized data structures
Distributed Computing Middleware db db db u Data Multidimensional Database (cont’d) db marts n Scaled-down version of a data warehouse that focuses on a specific area l e. g. , a department, a business process
Distributed Computing Massive Data Analysis Middleware db db db u Data db mining n Provides a means to extract patterns and relationships l Example: Analyze sales data to identify products that may be attractive to a customer u Amazon. com n Two buyer suggestions capabilities l Automated prediction of trends and behaviors l Automated discovery of previously unknown patterns n Example: Shopping cart analysis
Distributed Computing Network Enabling Software Middleware db db Supply Chain Management Enterprise Wide Systems Supplier Customer Relationship Management Enterprise Wide Systems Customer
Internet Era u IT Infrastructure (Web-enabled) n Hardware: Low-end PC with Browser, high-end Servers n Software: Web extensions n Database: Distributed Relational n Network: Use IP-based standards n Telecommunications: broadband n IT Personnel: Business analysts, technical specialties
Business use of the Internet: Electronic Commerce u B 2 C: Internet u B 2 B: Extranet u B 2 E: Intranet Individual Internet u E-business: n Subset of e-commerce n Transactions between business partners Enterprise Intranet Extranet Supplier/ Customer
Web-based Solutions u Early attempts to incorporate WWW into inter -organizational systems u Static, state-less web pages n Complicated navigation n Not “connected” to underlying data l Page not dynamically updated when data changes
Web Services db db db u Standards Hurdles for web services are evolving, not set u Security u Web services do not 'solve' interoperability between applications n Hence – need ERP
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