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0 4 2 2 BM1101 Information Systems and Database Design Database Systems and Networks DATABASE SYSTEMS 2 Objectives Identify and briefly describe the hierarchy of data Identify the adv...
0 4 2 2 BM1101 Information Systems and Database Design Database Systems and Networks DATABASE SYSTEMS 2 Objectives Identify and briefly describe the hierarchy of data Identify the advantages of the database approach to data management Identify the key factors that must be considered when designing a database Identify the various types of data models and explain how they are useful in planning a database Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 3 duplicated, or posted to a publicly accessible website, in whole or in part. Objectives Describe the relational database model Define the role of the database schema, data definition language, and data manipulation language Discuss the role of a database administrator and data administrator Identify the common functions performed by all database management systems Define the term big data Explain why big data represents a challenge and an opportunity Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 4 duplicated, or posted to a publicly accessible website, in whole or in part. Why Learn about Database Systems and Data Management? Databases capture data about changes For analysis and decision making To recognize new challenges and opportunities To track progress toward meeting key goals To identify when a change in tactics or strategy is needed Need to understand database systems and data management Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 5 duplicated, or posted to a publicly accessible website, in whole or in part. Database Fundamentals Database: Well-designed, organized, and carefully managed collection of data Can contribute to organizational success Providesmanagers and decision makers with timely, accurate, and relevant information built on data A database management system (DBMS) is a group of programs provided by the DBMS supplier that: Access and manage the database Provides an interface between the database and its users and other application programs Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 6 duplicated, or posted to a publicly accessible website, in whole or in part. Data Fundamentals Without data and the ability to process it: An organization could not successfully complete most business activities Data, Information and Knowledge Data consists of raw facts Information Collection of organized and processed data Has additional value beyond the value of the individual facts Knowledge Provides awareness and understanding of a set of information Shows how information can support a specific task or be used to reach a decision Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 7 duplicated, or posted to a publicly accessible website, in whole or in part. The Value of Information Value of information Directly linked to how it helps decision makers achieve their organization’s goals Helps people perform tasks efficiently and effectively Characteristics of quality information: Accessible Accurate Complete Economical Flexible Relevant Reliable Secure Simple Timely Verifiable Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 8 duplicated, or posted to a publicly accessible website, in whole or in part. Benefits Gained Through Use of High-Quality Data Improves innovation Improves worker efficiency, product and/or service quality, or the customer experience Raises productivity Employees can focus on the core mission No need to correct data errors Ensures compliance Ensures compliance with requirements Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 9 duplicated, or posted to a publicly accessible website, in whole or in part. The Data Hierarchy File Collection of entities Entity Person, place, or thing (object) for which data is collected, stored, and maintained Attribute Characteristic of an entity FIGURE 5.1 The data hierarchy Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 10 duplicated, or posted to a publicly accessible website, in whole or in part. The Data Hierarchy Domain Range of allowable values for a data attribute Data item Specific value of a data attribute Record Collection of attributes about a specific entity Primary key Attribute or set of attributes that uniquely identifies the record Foreign key Attribute in one table that refers to the primary key in another table Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 11 duplicated, or posted to a publicly accessible website, in whole or in part. The Database Approach Traditional approach to data management Each distinct operational system used data files dedicated to that system Database approach to data management Multiple information systems share a pool of related data Offers the ability to share data and information resources To use the database approach, additional software is needed i.e. Database Management System (DBMS) - an interface between a database and user of the database. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 12 duplicated, or posted to a publicly accessible website, in whole or in part. The Database Approach FIGURE 5.3 Database approach to data management In a database approach to data management, multiple information systems share a pool of related data. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 13 duplicated, or posted to a publicly accessible website, in whole or in part. Database Activities 1. Providing a user view of the database 2. Adding and modifying data 3. Storing and retrieving data 4. Manipulating the data and generating reports 5. Security Management and Backup recovery Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 14 duplicated, or posted to a publicly accessible website, in whole or in part. Providing a User View Schema: a description of the entire database (defining the database’s logical and physical structure) Identifies the tables and the attributes in each table Identifies the relationships between attributes and tables A schema can be part of the database or a separate schema file The DBMS can reference a schema to access the requested data in relation to another piece of data Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 15 duplicated, or posted to a publicly accessible website, in whole or in part. Providing a User View: Database schema FIGURE 5.4 Database schema represented in a visual diagram Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 16 duplicated, or posted to a publicly accessible website, in whole or in part. Creating and Modifying the Database Data definition language (DDL) A collection of instructions and commands used to define and describe data and relationships in a specific database Allows the database’s creator to describe data and relationships that are to be contained in the schema Data dictionary: a detailed description of all the data used in the database Can also include a description of data flows, information about the way records are organized, and the data-processing requirements Adherence to data dictionary standards makes it easy to share data among organizations Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 17 duplicated, or posted to a publicly accessible website, in whole or in part. Storing and Retrieving Data When an application program needs data, it requests the data through the DBMS DBMS functions as an interface between application program and database Concurrency control deals with the situation in which two or more users or applications need to access the same record at the same time FIGURE 5.5 Logical and physical access paths Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 18 duplicated, or posted to a publicly accessible website, in whole or in part. Manipulating Data and Generating Reports Once a database has been set up and loaded with data, it can produce reports, documents, and other outputs A DBMS can produce a wide variety of documents, reports, and other output that can help organizations achieve their goals Query by Example (QBE) is a visual approach to developing database queries or requests Data manipulation language (DML): a specific language, provided with a DBMS Allows users to access and modify the data, to make queries, and to generate reports Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 19 duplicated, or posted to a publicly accessible website, in whole or in part. Manipulating Data and Generating Reports FIGURE 5.6 Query by example Some databases use query by example (QBE) to generate reports and information. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 20 duplicated, or posted to a publicly accessible website, in whole or in part. Security management Security management Ensures data is protected against access by: Unauthorizedusers, physical damage, operating system failure, and simultaneous updating Defines and enforces user access privileges Grants users minimum privileges to do their jobs Backup and recovery Backup management Make backup copies of the database Backup copies can be used to restore the database Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 21 duplicated, or posted to a publicly accessible website, in whole or in part. Data Cleansing Also called data cleaning or data scrubbing The process of detecting and then correcting or deleting incomplete, incorrect, inaccurate, irrelevant records that reside in a database Improves quality of the data used in decision making Different from data validation Which involves the identification of 'bad data' and its rejection at the time of data entry Methods Cross-checking data against a validated data set Using data enhancement to augment the data in a database by adding related information Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 22 duplicated, or posted to a publicly accessible website, in whole or in part. Database Design Necessary to keep data well organized Database design Store all relevant data Provide quick access and easy modification Reflect organization’s business processes Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 23 duplicated, or posted to a publicly accessible website, in whole or in part. Database Design Considerations when building a database: Content: what data should be collected and at what cost? Access: what data should be provided to which users and when? Logical structure: how should data be arranged so that it makes sense to a given user? Physical organization: where should data be physically located? Archiving: how long to store? Security: how can data be protected from unauthorized access? Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 24 duplicated, or posted to a publicly accessible website, in whole or in part. Database Design Data modelling: Tool used to design a database Occurs at organizational level Called enterprise data modelling Occurs at specific business application level Enterprise data modeling: The enterprise data model provides a roadmap for building database and information systems. Identifies data entities and data attributes of greatest interest to the organization FIGURE 5.7 Enterprise data model Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 25 duplicated, or posted to a publicly accessible website, in whole or in part. Database Design Entity-relationship (ER) diagrams: Data model used to analyze and communicate data needs Works at the individual project or application level Uses graphical symbols to show the organization of and relationships between data Identify data entities and their associated data attributes Identify the relationships among the entities of interest Many notation styles exist for drawing an ER diagram Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 26 duplicated, or posted to a publicly accessible website, in whole or in part. Database Design - ERD FIGURE 5.8 Entity-relationship (ER) diagram for a customer order database Development of ER diagrams helps ensure that the logical structure of application programs is consistent with the data relationships in the database Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 27 duplicated, or posted to a publicly accessible website, in whole or in part. Relational Database Model Relational database model: a simple but highly useful way to organize data into collections of two- dimensional tables called relations Each row in the table represents an entity Each column represents an attribute of that entity Column table data Integer number, decimal number, date, text, etc. Constrained to be certain type, length, or to have a value between two limits Primaryand foreign keys enable table relationships User queries perform operations on the database Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 28 duplicated, or posted to a publicly accessible website, in whole or in part. Relational Database Model FIGURE 5.9 Relational database model In the relational model, data is placed in two-dimensional tables, or relations. As long as they share at least one common attribute, these relations can be linked to provide output useful information. In this example, all three tables include the dept. number attribute. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 29 duplicated, or posted to a publicly accessible website, in whole or in part. Manipulating Data in a Relational Database Selecting: eliminating rows according to certain criteria Projecting: eliminating columns in a table Joining: combining two or more tables through common data attributes to form a new table Data normalization: eliminates data redundancy Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 30 duplicated, or posted to a publicly accessible website, in whole or in part. Manipulating Data in a Relational Database Suppose the president of a company wants to find out the name of the manager of the sales manual project as well as the length of time the manager has been with the company. Assume the company has Manager, Department and Project tables. The diagram shows the relationship among the manager, department, and project tables. FIGURE 5.10 ER diagram Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 31 duplicated, or posted to a publicly accessible website, in whole or in part. Manipulating Data in a Relational Database Suppose the president of a company wants to find out the name of the manager of the sales manual project as well as the length of time the manager has been with the company. To find the name and hire date of the manager working on the sales manual project, the president needs three tables: project, department, and manager. The project description (sales manual) leads to the department number (598) in the project table, which leads to the manager’s social security number (098-40-1370) in the department table, which leads to the manager’s last name (fiske) and hire date (01-05-2001) in the manager table FIGURE 5.11 Linking data tables to answer an inquiry Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 32 duplicated, or posted to a publicly accessible website, in whole or in part. Relational Database Management Systems (DBMSs) Creating and implementing the right database system ensures that the database will support both business activities and goals Capabilities and types of database systems vary considerably Structured Query Language (SQL): a special-purpose programming language for accessing and manipulating data stored in a relational database Has become an integral part of most relational databases e.g. in Microsoft Access Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 33 duplicated, or posted to a publicly accessible website, in whole or in part. SQL Databases Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 34 duplicated, or posted to a publicly accessible website, in whole or in part. Popular Relational Database Management Systems Open-Source Relational Relational DBMS for Relational DBMS for DBMS Individuals and Workgroups Workgroups and Enterprise MySQL Microsoft Access Oracle PostgreSQL IBM Lotus Approach IBM DB2 MariaDB Google Base Sybase Adaptive Server SQL Lite OpenOffice Base Teradata CouchDB Airtable Microsoft SQL Server MongoDB Knack Progress OpenEdge TABLE 5.7 Popular database management systems Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 35 duplicated, or posted to a publicly accessible website, in whole or in part. Popular Relational Database Management Systems Database as a service (DAAS) Database stored on a service provider’s servers Database accessed by service subscriber (client) over the Internet Database administration handled by the service provider DaaS advantage Eliminates the installation, maintenance, and monitoring of in-house databases Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 36 duplicated, or posted to a publicly accessible website, in whole or in part. Using Databases with Other Software DBMSs can act as front-end or back-end applications Front-end applications interact directly with people Back-end applications interact with other programs or applications Spin-off database applications include: Big data, data warehouses and data marts, and business intelligence Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 37 duplicated, or posted to a publicly accessible website, in whole or in part. Data Management Data management An integrated set of functions that defines the processes by which data is obtained, certified fit for use, stored, secured, and processed in such a way as to ensure that the accessibility, reliability, and timeliness of the data meet the needs of the data users within an organization Data governance Defines the roles, responsibilities, and processes Ensures that data can be trusted and used by an entire organization Ensures people identified and in place who are responsible for fixing and preventing issues with data Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 38 duplicated, or posted to a publicly accessible website, in whole or in part. Data Management Data management is driven by a variety of factors: The need to meet external regulations designed to manage risk associated with financial misstatement The need to avoid the inadvertent release of sensitive data The need to ensure that high data quality is available for key decisions Data governance requires business leadership and active participation Use of a cross-functional team is recommended Team should consist of executives, project managers, line-of-business managers, and data stewards A data steward is an individual responsible for management of critical data elements Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 39 duplicated, or posted to a publicly accessible website, in whole or in part. Database Administration Database administrators (DBAs): skilled and trained IS professionals Works with users to define their data needs Applies database programming languages to craft a set of databases to meet those needs Tests and evaluates databases Implements changes to improve their databases’ performance Assures that data is secure from unauthorized access Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 40 duplicated, or posted to a publicly accessible website, in whole or in part. Data Management Data lifecycle management (DLM) A policy-based approach to managing the flow of an enterprise’s data Manages enterprise’s data flow From initial acquisition or creation and storage Until data becomes outdated and is deleted Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 41 duplicated, or posted to a publicly accessible website, in whole or in part. Summary Well-designed and well-managed databases help with decision making High-quality data benefits: Improvedecision making, increase customer satisfaction, increase sales, improve innovation, raise productivity, and ensure compliance Strong data management program needed to ensure high-quality data Data governance is the core component of data management We have entered an era where organizations are grappling with a tremendous growth in the amount of data available and struggling how to manage and make use of it Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 42 duplicated, or posted to a publicly accessible website, in whole or in part. NETWORKS 43 Objectives Identify and briefly describe three network topologies and four different network types Identify and briefly discuss several types of both guided and wireless communications Identify several network hardware devices and define their functions Briefly describe how the Internet and the Web work, including various methods for connecting to the Internet Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 44 duplicated, or posted to a publicly accessible website, in whole or in part. Objectives Outline the process and tools used in developing Web content and applications List and describe several Internet and Web applications Explain how intranets and extranets use Internet technologies, and describe how the two differ Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 45 duplicated, or posted to a publicly accessible website, in whole or in part. Why learn about Networks Today’s decision makers need to access data wherever it resides thus, effective communication is essential to the success of an organization’s operations. In today’s high speed global business world, organizations must be able to take advantage of the capabilities that communications technologies offers Strive to increase revenue, reduce time to market and enable collaboration with their suppliers, customers and business partners by using networks. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 46 duplicated, or posted to a publicly accessible website, in whole or in part. Network Fundamentals Computer network the communications media, devices, and software needed to connect two or more computer systems or devices Network nodes the computers and devices on the networks Organizations can use networks to share hardware, programs, and databases to transmit and receive information allowing for improved organizational effectiveness and efficiency. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 47 duplicated, or posted to a publicly accessible website, in whole or in part. Network Topology Network topology The shape or structure of a network, including the arrangement of the communications links and hardware devices on the network Three most common network topologies Starnetwork Bus network Mesh network Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 48 duplicated, or posted to a publicly accessible website, in whole or in part. Network Topology Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 49 duplicated, or posted to a publicly accessible website, in whole or in part. Network Types A personal area network (PAN) supports the interconnection of information technology close to one person A local area network (LAN) connects computer systems and devices within a small area (e.g., an office or a home) A metropolitan area network (MAN) connects users and their devices in an area that spans a campus or city Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 50 duplicated, or posted to a publicly accessible website, in whole or in part. Network Types A wide area network (WAN) connects large geographic regions WANs consist of: Computer equipment owned by the user Data communications equipment and telecommunications links provided by various carriers and service providers Communications may involve transborder data flow Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 51 duplicated, or posted to a publicly accessible website, in whole or in part. Channel Bandwidth Channel bandwidth the capacity of a communications channel to carry traffic i.e. the rate at which data is exchanged Usuallymeasured in megabits bits per second The higher the bandwidth, the more traffic that can be carried Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 52 duplicated, or posted to a publicly accessible website, in whole or in part. Network Latency Network latency Measures how long it takes for a unit of data to get to its destination and back again Measured in milliseconds (ms) or thousandths of a second Low-latency networks Small delays occur High-latency networks Experience long delays High latency creates bottlenecks Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 53 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Any material substance that carries an electronic signal to support communications between a sending and a receiving device Two broad categories Guided (wired) transmission media: signals are guided along a solid medium Wireless: the signal is broadcast over airwaves as a form of electromagnetic radiation Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 54 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Wireless Technologies Wireless transmission involves the broadcast of communications in one of three frequency ranges i.e. radio, microwave, or infrared frequencies In some cases, use of wireless communications is regulated The signal must be broadcast within a specific frequency range to avoid interference with other wireless transmissions Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 55 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Near field communication (NFC): a very short-range wireless connectivity technology Designed for consumer electronics, cell phones, and credit cards Bluetooth a wireless communications specification that describes how cell phones, computers, personal digital assistants, etc., can be interconnected devices interconnected over distances of 10 to 30 feet at a rate of about 2 Mbps Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 56 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Wi-Fi A wireless telecommunications technology brand owned by the Wi-Fi Alliance Employs a wireless access point (a transmitter with an antenna) that receives the signal and decodes it Translatessignals into a radio signal and sends it to device’s wireless adapter The area covered by one or more interconnected wireless access points FIGURE 7.7 Wi-Fi network is called a “hot spot” In a Wi-Fi network, the user’s computer, smartphone, or cell phone has a wireless adapter that translates data into a radio signal and transmits it using an antenna. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 57 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 58 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Microwave Transmission Microwave is a high-frequency (300 MHz–300 GHz) signal sent through the air Common forms of satellite communications: Geostationary satellite Low earth orbit (LEO) satellite Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 59 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media Historical perspective 1G (first generation) of wireless communications standards: originated in the 1980s; based on analog communications 2G (second generation) employed fully digital networks; superseded 1G networks in the early 1990s 3G supports wireless voice and broadband speed data communications in a mobile environment at speeds of 2 to 4 Mbps 4G wireless provides increased data transmission rates 3 to 20 times the speed of 3G networks for mobile devices 4G networks are based on Long Term Evolution (LTE) LTE is a standard for wireless communications for mobile phones based on packet switching Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 60 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Media 5G Wireless Communications Advantages over 4G networks More bandwidth Lower latency Supports many more devices Enables exciting new applications Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 61 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Software Network operating system (NOS) Systems software that controls the computer systems and devices on a network Linux, UNIX, Windows Server, and Mac OS X are common NOSs Network-management software: Desktop manager monitors individual computers and shared hardware use, scans for viruses, and ensures software license compliance Protects software from being copied, modified, or downloaded illegally Locates telecommunications errors and potential network problems Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 62 duplicated, or posted to a publicly accessible website, in whole or in part. Communications Software Mobile device management (MDM) software Manages and troubleshoots mobile devices remotely, pushing out applications, data, patches and settings A central control group can maintain group policies for security, control system settings, ensure malware protection is in place for mobile devices used across the network, and make it mandatory to use passwords to access the network Software-Defined Networking (SDN) Emerging approach to networking Network administrators manage a network through a controller No physical access required Automates tasks Enables dynamic response to application requirements Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 63 duplicated, or posted to a publicly accessible website, in whole or in part. The Internet and World Wide Web FIGURE 7.10 Number of Internet users worldwide Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 64 duplicated, or posted to a publicly accessible website, in whole or in part. How the Internet Works Internet backbone: one of the Internet’s high-speed, long-distance communications links IP protocol The set of rules used to pass packets from one host to another Transmission Control Protocol (TCP): the widely used transport layer protocol that most Internet applications use with IP IP address: a 64-bit number that identifies a computer on the Internet FIGURE 7.11 How the Internet works Data is transmitted from one host computer to another on the Internet. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 65 duplicated, or posted to a publicly accessible website, in whole or in part. How the Internet Works Uniform Resource Locator (URL) a Web address that specifies the exact location of a Web page using letters and words that map to an IP address and a host location Internet Corporation for Assigned Names and Numbers (ICANN) is responsible for managing IP addresses and Internet domain names Domain names must adhere to strict rules Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 66 duplicated, or posted to a publicly accessible website, in whole or in part. How the Internet Works Network hardware Switch Keeps a record of the MAC address of all the devices connected to it Determines port a frame of data should be directed to Router Directs data packets to other networks until each packet reaches its destination Routing Use dynamic routing to move packets Packets may arrive at the destination device out of order Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 67 duplicated, or posted to a publicly accessible website, in whole or in part. Accessing the Internet Connecting via LAN server Connection method of businesses and organizations that manage a local area network (LAN) Connecting via Internet service providers Internet service provider (ISP) is any organization that provides Internet access to people You must have an account with the service provider along with software and devices that support a connection via TCP/IP Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 69 duplicated, or posted to a publicly accessible website, in whole or in part. Accessing the Internet Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 70 duplicated, or posted to a publicly accessible website, in whole or in part. Accessing the Internet Dial-up Internet connection uses modem and standard phone line Other options include: Cable modem connections DSL connections Satellite connections Wireless Connection Internet service over cellular and Wi-Fi networks has become common Thousands of public Wi-Fi services available Cell phone carriers provide Internet access for smartphones, notebooks, and tablets Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 71 duplicated, or posted to a publicly accessible website, in whole or in part. How the Web Works The Internet The infrastructure on which the Web exists Made up of computers, network hardware such as routers and fiber-optic cables, software, and the TCP/IP protocols The World Wide Web (Web) Consists of server and client software, the hypertext transfer protocol (http), standards, and markup languages that combine to deliver information and services over the Internet Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 72 duplicated, or posted to a publicly accessible website, in whole or in part. Client/Server Systems Client/server architecture features multiple computer platforms dedicated to special functions, e.g., database management, printing, or communications These platforms are called servers. Each server is accessible by all computers on the network. A client is any computer that sends messages requesting services from the servers on the network Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 73 duplicated, or posted to a publicly accessible website, in whole or in part. Client/Server Systems FIGURE 7.12 Client/Server Architecture Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 74 duplicated, or posted to a publicly accessible website, in whole or in part. How the Web Works Hyperlink: highlighted text or graphics in a Web document that, when clicked, opens a new Web page Web browser: Web client software used to view Web pages Examples: Internet Explorer, Firefox, Chrome, and Safari Web site: a collection of pages on one particular topic, accessed under one Web domain Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 75 duplicated, or posted to a publicly accessible website, in whole or in part. How the Web Works Hypertext Markup Language (HTML): the standard page description language for Web pages Tells the browser how to display font characteristics, paragraph formatting, page layout, image placement, hyperlinks, and the content of a Web page HTML tags tell the Web browser how to format text and elements to be inserted Extensible Markup Language (XML): a markup language designed to transport and store data on the Web Cascading Style Sheets (CSS): a file or portion of an HTML file that defines the visual appearance of content in a Web page Uses special HTML tags to globally define characteristics for a variety of page elements as well as how those elements are laid out on the Web page Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 76 duplicated, or posted to a publicly accessible website, in whole or in part. How the Web Works FIGURE 7.14 XML, CSS, and HTML Today’s Web sites are created using XML to define content, CSS to define the visual style, and HTML to put it all together. Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 77 duplicated, or posted to a publicly accessible website, in whole or in part. Web Programming Languages JavaScript Other client-side programming A popular programming language languages include: for client-side applications ASP.NET Use to create Web pages that C respond to user actions C++ Java Perl An object-oriented programming PHP language from Sun Microsystems Python based on C++ Allows small programs (applets) to be embedded within an HTML document Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 78 duplicated, or posted to a publicly accessible website, in whole or in part. Web Services Standards and tools that streamline and simplify communication among Web sites XML The key to Web services Used within a Web page to describe and transfer data between Web service applications Amazon Web Services (AWS) Basic infrastructure that Amazon employs to make the contents of its online catalog available to other Web sites or software applications Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 79 duplicated, or posted to a publicly accessible website, in whole or in part. Developing Web Content and Applications Options for creating a Web site Hire someone to design and build it Do it yourself Use an online service to create the Web pages Use a Web page creation software tool Use a plain text editor to create the site Popular tools for creating Web pages and managing Web sites Adobe Dreamweaver, RapidWeaver (for Mac developers), and Nvu Many products make it easy to develop Web content and interconnect Web services Example: Microsoft’s.NET platform which allows developers to use various programming languages to create and run programs Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 80 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications The original Web—Web 1.0 One-directional resource Published information was for viewing only Web 2.0 and the Social Web Web 2.0 theWeb as a computing platform that supports software applications and the sharing of information among users Social networking Web sites enable users to share information abut themselves and to find, meet, and converse with others Enterprise 2.0: using social media in business Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 81 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications News The Web is a powerful tool for keeping informed about local, state, national, and global news Education and Training Web is ideally suited as a tool for sharing information and a primary repository of information on all subjects Distance education offers classes via the Web Job Information Providing information about a businesses and its products via Web site and social media increases the company’s exposure and reputation The Web is an excellent source of job-related information Examples: www.linkedin.com, www.monster.com, and www.careerbuilder.com Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 82 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Search Engines and Web Research Search engine Information on the Web is found by specifying keywords The market is dominated by Google Search engine optimization (SEO) is a process for driving traffic to a Web site by using techniques that improve the site’s ranking in search results Online research databases allow visitors to search for information in thousands of journal, magazine, and newspaper articles Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 83 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Instant messaging Online, real-time communication between two or more people who are connected via the Internet Microblogging, Status Updates, and News Feeds Twitterallows users to send short text updates from a smartphone or a Web browser to their Twitter followers Popularity of Twitter has caused social networks, such as Facebook, LinkedIn, and Tumbler, to include Twitter-like news or blog post feeds Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 84 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Conferencing The Internet has made it possible for those involved in teleconferences to share computer desktops GoToMeeting enables employees to attend training without leaving their assigned stations Telepresence systems use high-resolution video and audio with high- definition displays Google Voice and Skype allow video chats Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 85 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Blogging and Podcasting Web log (blog): a Web site that people can create and use to write about their observations, experiences, and opinions on a wide range of topics Video log (vlog): blogging with video content Podcast: an audio broadcast over the Internet Online Media and Entertainment Content streaming: a method of transferring large media files over the Internet The data stream of voice and pictures plays continuously as the file is being downloaded Music Internet radio is digitally delivered to your computer over the Internet Downloaded music may employ Digital Rights Management (DRM) technology to limit the user’s ability to make copies Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 86 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Online Media and Entertainment (cont’d) Movies, Video, and Television Hulu Web site and Internet-based television platforms (e.g., Netflix and Joost) provide television programming Vudu provides access to online movies YouTube supports the online sharing of user-created videos Online Games and Entertainment Themarket for Internet gaming is very competitive and constantly changing Many video games are available online Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 87 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Shopping Online Shopping on the Web can be convenient, easy, and cost effective Retail stores provide access to many products that may be unavailable in local stores Online clearinghouses, Web auctions, and marketplaces provide a platform for businesses and individuals to sell their products and belongings eBay is the most popular online auction/marketplace Businesses benefit from shopping online Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 88 duplicated, or posted to a publicly accessible website, in whole or in part. Internet and Web Applications Travel, Geolocation, and Navigation TheWeb has had a profound effect on the travel industry and the way people plan and prepare for trips Mapping and geolocation tools MapQuest, Google Maps, and Bing Maps Geographic information systems (GIS) provide geographic information layered over a map Geo-tagging is possible on Twitter and Facebook Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 89 duplicated, or posted to a publicly accessible website, in whole or in part. Intranets and Extranets Intranet an internal corporate network built using Internet and World Wide Web standards and technologies Extranet a network based on Web technologies that links resources of a company’s intranet with its customers, suppliers, or other business partners Virtual private network (VPN) Need User ID and Type User Password? A secure connection between Internet Anyone No two points on the Internet Intranet Employees Yes Extranet Business partners Yes Table 7.5 Summary of Internet, intranet, and extranet users Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 90 duplicated, or posted to a publicly accessible website, in whole or in part. Summary A network has many fundamental components, which enable people to meet personal and organizational objectives Together, the Internet and the World Wide Web provide a highly effective infrastructure for delivering and accessing information and services Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 91 duplicated, or posted to a publicly accessible website, in whole or in part. Summary A network has many fundamental components, which enable people to meet personal and organizational objectives Together, the Internet and the World Wide Web provide a highly effective infrastructure for delivering and accessing information and services Stair/Reynolds, Principles of Information Systems, 14th Edition. © 2021 Cengage. All Rights Reserved. May not be scanned, copied or Week 4 91 duplicated, or posted to a publicly accessible website, in whole or in part.
