Week 3 Discussion Management of Information Systems

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Week 3 Objectives

Explain the difference between application software and system software

Enumerate the different generations of programming languages and explain how they differ

Cite the latest major developments in application and system software

Identify and explain the roles of Web programming languages

Objectives this week are to:

Explain the difference between application software and system software

Enumerate the different generations of programming languages and explain how they differ

Cite the latest major developments in application and system software

Identify and explain the roles of Web programming languages

Explain the types and uses of Web site design tools

Clarify the differences between proprietary software and open source software

List characteristics that are important in evaluating packaged software applications for business use

Understand the problem of software piracy and how it affects businesses and consumers

Describe business and home applications of digital telecommunications

Identify the major media and devices used in telecommunications

Explain the concept of network protocols

Compare and contrast various networking and Internet services

List networking technologies and trends that are likely to have an impact on businesses and information management in the near future

Discuss the pros and cons of telecommuting

Figure 5.1 The evolution of programming languages

Applications are computer programs that contribute to productivity

Software is a series of instructions to a computer that execute processes

Two major categories of software:

Application software: enables task completion

System software:

Enables applications to run on a computer

Manages components and devices

Programs are needed for every computer operation

Programming or coding is the process of writing computer programs

Machine language, consists of long sequences of 0s and 1s and is the only language that hardware understands

Assembly language is uses words for commands and is easier to program than machine language

High-level programming languages: use English-like statements

Software development kits (SDKs) are tools used to develop software without having a detailed knowledge of programming languages

Third-generation languages (3GLs): known as “procedural” languages

Require a Programmer to detail a logical procedure

3GLs include languages such as COBOL, FORTRAN, BASIC, RPG, Pascal, and C

One 3GL statement is the equivalent of five to ten assembly language statements

Fourth-generation languages (4GLs) use more English-like statements

4GLs sped up the development process

They were built around database management systems

4GLs include many preprogrammed procedures

One 4GL statement is the equivalent of several 3GL statements

Structured Query Language (SQL) is an example

Debugging is a process of locating and fixing program errors

Advantages of Higher-Level Programming are

ease of learning the language

Ease of Programming

Significantly shorter code

Ease of debugging

And Ease of Maintenance

Disadvantages of Higher-Level Programming are

Less control over hardware,

Less efficient memory use,

And Programs run more slowly

Visual Programming

Visual programming languages: create graphical screen objects by selecting icons from a palette

Common visual programming languages

Microsoft Visual Basic

Embarcadero Delphi

Micro Focus COBOL

ASNA Visual RPG

Visual C++

Developer can still work at the code level

Visual programming languages create graphical screen objects by selecting icons from a palette

Common visual programming languages

Microsoft Visual Basic

Embarcadero Delphi

Micro Focus COBOL

ASNA Visual RPG

Visual C++

Developers can still work at the code level

Object-oriented programming (OOP) languages provide a modular approach to programming

Advantages:

Ease of maintenance

Efficiency in application development

Object: contains data elements (data members) and the methods to manipulate that data

Data members can only be accessed through the object’s methods

OOP Advantages

Requires less code than other languages

Requires less time than programming in other languages

Enhances program modularity and reusability

Makes code maintenance easier

Enhances ability to create user-friendly interface

Appropriate for graphic- and sound-enhanced applications

Objects are reusable and are combined to create complex programs

Popular OOP languages include Java, C++/C#, and Visual Basic

There is an increasing amount of software developed for the Web using languages such as Java, JavaScript, and PHP

An Applet is code produced by a Web programming language that runs the same way on different operating systems

Figure 5.5 A compiler converts higher-level language code (source code) into machine language (object code), which the computer can execute © Cengage Learning 2015

Programming language translators render source code into object code.

Source code is a program as originally written by the developer

Object code is program consisting of machine language that can be run by the computer

A compiler translates the entire source code into object code but does not execute the code.

A compiler scans code for syntax errors and generates error messages if syntax errors are found.

An interpreter scans one statement at a time. If a statement is error-free, it is interprets it into machine language and executes the statement. An interpreter proceeds through the lines of code until an error occures, or the end of the program is encountered

Application Software

Application software allows nonprogrammers to develop their own tools

Application-specific software: programs designed to perform specific jobs

General-purpose application software: programs that serve multiple purposes

Usually comes as packaged software

Packaged software: software that is ready to install from external storage media such as CDs

Application software allows nonprogrammers to develop their own tools

Application-specific software: programs designed to perform specific jobs

General-purpose application software: programs that serve multiple purposes

Usually comes as packaged software

Packaged software: software that is ready to install from external storage media such as CDs

Productivity applications or tools assist in normal office work

These applications include word processors, spreadsheets, presentation tools, file/database software, graphics programs, desktop publishing tools, etc.

Word processors create text documents

Spreadsheets store numbers and perform complex mathematical, statistical, and financial analysis functions

Presentation tools develop impressive presentations quickly

File/database management tools create and manipulate local or shared databases

Graphics programs create intricate graphical images and manipulate digital photographs

Desktop publishing tools develop items for publication, such as pamphlets, newsletters, cards, calendars, etc.

Project management tools help plan projects and track progress

Suite: collection of various applications that perform multiple interrelated functions

Examples include Microsoft Office, IBM Lotus SmartSuite, and the free Apache OpenOffice.org

Hypermedia and Multimedia

Hypermedia: a feature that enables users to access information by clicking text or graphics

Web authoring tools enable hypermedia features

Often part of other applications such as word processors and presentation tools

Hypermedia is a feature of digital media that enables users to access information by clicking text or graphics

Web authoring tools enable hypermedia features.

In addition to the Web, hypermedia can be found in other applications. Hypermedia is often encountered in documents created using applications such as word processors and presentation tools

Multimedia is software involving many different types of data, such as text, images, audio and video.

Multimedia is often used in:

Education where lessons are presented in multimedia

Research where data is compiled and integrated

Training exercises where simulations of real-world situations occur

And, in business situations where compound documents are filed and used electronically; and in interactive websites

A mashup is an integrated application containing some or all features from several applications

A mashup provides enhanced features for the end user.

Web Site Design Tools are used to develop and change the content of Web pages

Popular packages include

Microsoft SharePoint Designer and Expression Web, and Adobe Muse and AdobeDreamweaver

Wordpress, and other software enables websites implemented using a blog environment

Groupware is an application that enables sharing of ideas and information resources among group members

It supports real-time collaboration via web technologies

Groupware allows for remote and asynchronous collaboration

It eliminates travel times and facilitates expression and exchange of ideas

Examples: are Wiggio and Google Drive

3D Geographic Software is used to develop three-dimensional models of geographic locations

Models are created from land and aerial photographs

3D geographic software helps with navigation when tied to global positioning system software

3D software can create virtual versions of existing items or create new virtual items

Figure 5.6 The operating system mediates the computer system’s resources and application software as well as controls peripheral and network devices © Cengage Learning 2015

System software: deals with essential operations between the user and computer such as:

Loading, copying, and deleting files

Managing memory resources

Operating peripheral equipment

System software encompasses compilers and interpreters

Applications must be compatible with system software

An Operating system (OS) is the most important program on the computer

It, recognizes input from keyboard and mouse

It sends output to computer display

It keeps track of files and directories

It runs applications

It manages memory

An operating system is usually developed using low-level programming languages such as assembly languages

Operating systems are known as “platforms.” Examples are Windows, OSX ,iOS, Unix, Linux, Ubuntu, and Android

Application program interfaces (APIs) are software included in the OS that can be used by application program developers

In a computer’s logical operation,

A user interacts with a user interface using menus, icons, and application commands

applications convert user input into commands

The OS commands the CPU to carry out the operation

The OS allows applications to use the CPU, memory, input and output devices, and the file system

Utilities perform other OS functions, such as hardware diagnostics, file comparison, and file sorting

Figure 5.7 Computer systems operate on a number of layers, beginning with the user interface and moving into the computer’s hardware © Cengage Learning 2015

OS must manage the system by allocating hardware resources to applications

OS provides several services, including:

User interface

Memory allocation, including the use of virtual memory (hard disk used as an extension of RAM)

Plug-and-play (PnP): recognize and run a device as soon as it is physically attached

A driver is software that enables OS to control a device

Additional OS services include:

Database management

Networking

Security

Different computers and types of microprocessors use different OSs

Popular PC operating systems

Windows

Linux

Mac OS

OSs for mobile environments used with smartphones and tablets

OSs noted for stability include UNIX, Mac OS X, and Linux

Other types of system software include:

Compilers and interpreters

Communications software

Utilities

Database management systems

Communications software supports transmission and reception of data across computer networks

Utilities include antivirus programs, firewalls, and other programs that detect and remove unwanted files and applications

Open Source Software

Proprietary software: sold/licensed for profit

Source code is private and not available

Developer retains all rights to the software; user purchases a license to use the software

Open source software: free source code

Developed through voluntary collaboration of programmers

Reviewed by many programmers → fewer bugs

Examples includes Mozilla Firefox, Drupal, MySQL, PERL, and OpenOffice.org suite

Proprietary software is sold or licensed for profit

The source code is private and not available

The developer retains all rights to the software; users must purchase a license to use the software

Open source software is free source code

It is developed through voluntary collaboration of programmers

Open source software is reviewed by many programmers, which means that it contains fewer bugs

Examples includes Mozilla Firefox, Drupal, MySQL, PERL, and OpenOffice.org suite

Linux is the best known open source OS

Free versions are available and there are versions that charge for support and additional features

A disadvantage is that there are a limited number of applications that run on it

Linux is popular because of its stability and versatility

It runs on mainframes, PCs, handhelds, and electronic devices

Software is usually licensed

A software license provides limited permission to use the software

A time-limited license requires annual fees

Software licensing models are:

A permissive model where anyone can use and sell modified versions of the software

General Public License (GPL) where anyone can use and make modified versions, but cannot sell modified versions for profit

And Proprietary, where code is owned by someone who has the right to sell or license it to others

Software as a service provides application software over a network, such as the Internet or a private network. The software is developed and maintained by a third-party provider

The applications are offered to organizations for a recurring fee

The third-party provider is referred to as an application service provider (ASP)

An ASP develops and maintains the software on their hardware and provides maintenance, support, and hardware operations

Figure 5.9 Sample software evaluation form © Cengage Learning 2015

Factors to consider when purchasing large software packages are complex and include

Cost

Time to implement

Cost of interrupting operations

And modification costs to customize the software

Other factors to consider when purchasing software are

Fitness for purpose,

Ease of learning to use

Ease of use

Compatibility with other software

The reputation of the vendor

Support

And Networking

Telecommunications in Business

Telecommunications: the transmittal of data and information from one point to another

Allows communications over large distances

Telephone, e-mail, and the web rely on fast, reliable telecommunications

Networking technologies have brought about several improvements to business processes

Telecommunications is the transmittal of data and information from one point to another

Telecommunications allows communications over large distances

The telephone, e-mail, and the web rely on fast, reliable telecommunications

Networking technologies have brought about several improvements to business processes

Telecommunications-supported improvements are:

Business communication, including e-mail, voice mail, instant messaging, faxing, file transfer, mobile telephony, and teleconferencing

Greater efficiency in information delivery that is immediate and not constrained by geographical distance

Better distribution of data from central storage with both local and remote access

Instant transactions, using web and wireless technologies

Flexible and mobile workforce: telecommuting and wireless connectivity for remote workers

Alternative channels: voice, radio, television now available via the Web also

Network security is a challenge

Telecommunications in daily use are:

Cellular phones

Videoconferencing

Wireless payments and warehousing

Peer-to-peer (P2P) file sharing

Web-empowered commerce

Cellular Phones

Name is derived from areas of service, called cells

Each cell has a computerized transceiver

Transmits and receives signals

Can transmit and receive calls almost anywhere

Cell phones provide other capabilities, including:

Digital cameras

GPS

Major advantage is mobility

The name cellular phone was derived from areas of service, called cells

Each cell has a computerized transceiver that transmits and receives signals

Cellular phones can transmit and receive calls almost anywhere and provide other capabilities, including:

Digital cameras

GPS

The major advantage is mobility

Networking professionals refer to generations of mobile communication technologies as:

First generation (1G) which was analog

Then, second generation (2G) which provided digital voice encoding

Third generation (3G) increased speeds that supported video, videoconferencing, and full Internet access

Fourth Generation (4G) is digital only, with packet switching and tighter security

Videoconferencing is holding meetings through conferencing software and hardware that transmits images, audio and video to multiple locations simultaneously

It brings together conference rooms that are thousands of miles apart

Videoconferencing produces savings in multiple areas, including:

Travel

Lodging

Car fleets

Employees’ time

Wireless payments and warehousing uses radio frequency identification (RFID) to

enables rapid transactions and payments

RFID is used at gas stations for payment at pump, in vehicles for automatic toll road payment, and used to track and locate items in warehouses

Near-field communication (NFC) is a standard communication protocol to create a radio connection between two devices

Near-field communication is used for mobile payment that is payment performed using a mobile device and in digital wallets, that are electronic devices that contain consumer information setup for fast transactions when purchasing goods online or at particular locations via a smartphone.

Peer-to-peer (P2P) file sharing is used to locate and download files from any online computer through Internet using applications such as:

LimeWire

BitTorrent

Vuze

Used extensively to download music and video files, often in violation of copyright laws

Concerns include security and malware

Web-empowered commerce is characterized by increasingly fast communication that allows organizations and individuals to:

Conduct business

Research

Market

Educate and train

Shop, purchase, and pay

Entire industries have been created by the web, such as online exchanges and auctions

Figure 6.1 Transmission speed measurement units © Cengage Learning 2015

Professionals should understand technology concepts:

To participate in decision making

In order to select networking equipment and services

Bandwidth and networking media are important considerations

Bandwidth: speed at which data is communicated

Also called transmission rate or bit rate

Bits per second (bps): unit of measure for bandwidth

Broadband: communications medium that can carry multiple transmissions simultaneously

Examples: cable television, DSL (digital subscriber line), fiber-optic cables, and most wireless connections

Several types of communications media

Tangible media includes:

Twisted pair cable

Coaxial cable

Optical fiber

Intangible media includes:

Microwave radio technologies

Figure 6.2 Networking media © Cengage Learning 2015

Twisted pair cable is pairs of insulated copper wires twisted together

It is flexible, reliable, and low cost

It connects devices with an RJ-45 plug-in connector

Coaxial cable is for cable television transmission

Additionally, it is used for Internet connections via cable

Optical fiber uses light to represent bits

It I not susceptible to EMI (electromagnetic interference)

Optical fiber an carry signals for long distances

Radio frequency (RF) technologies use radio waves to carry bits

Popular examples are Wi-Fi and Bluetooth

Microwaves are high-frequency radio waves that can carry signals over long distances with high accuracy

For outside transmission, weather conditions may degrade the quality

Microwave signals can be transmitted by satellite links

Electrical power lines are part of the electrical power grid and can be used for telecommunications by Broadband over Power Lines (BPL) or Power Line Communication (PLC)

Considerations for network media acquisition are:

Availability,

Current and potential bandwidth,

and vulnerability to electro-magnetic interference (EMI) or radio frequency interference (RFI)

Networks

Network: combination of devices (or nodes) connected through a communication media

Any compatible device that can transmit and receive on a network can be part of a network

A Network is a combination of devices (or nodes) connected through a communication medium

Any compatible device that can transmit and receive on a network can be part of a network

Computer networks are classified by reach and complexity

Basic types of networks are LANs, MANs, and WANs

Local area networks (LANs) are established by a single organization and shared among employees

Server-based LAN is when a central server controls communications

Peer-to-peer LAN has no central device

Wireless LANs (WLANs) offer advantages such as,

Easier installation,

More scalable,

And, more flexibility in that equipment can be easily moved

Scalability is the ease of expanding a system

A Wireless LAN drawback is that wireless networks are less secure than wired LANs

A Metropolitan area network (MAN):

Links multiple LANs within a large city

A Metropolitan area network uses fiber optic or wireless broadband connections between LANs

A Wide area network (WAN) is a far-reaching system of networks composed of LANs or MANs

May be public or private

Value-added networks (VANs):

Are networks with enhanced services offered by outside vendors

VANS provide reliability, management, and maintenance of networks for an organization

Internet service providers (ISPs)

Preferred method of conducting e-commerce

Less costly than VANs

Personal area network (PAN) is a wireless network designed for handheld and portable devices

Used by one or two people

Transmission speed is slower

Maximum distance is about ten meters

Networking Hardware

Networks use a variety of devices to connect computers and peripheral devices

Network interface card (NIC) connects a device to a hub, switch, bridge, or router, which connects to a LAN or WAN

Switch: a common device often used as a central location to connect computers or devices to a local network

Bridge: connects two networks

Networks use a variety of devices to connect computers and peripheral devices

A Network interface card (NIC) connects a device to a hub, switch, bridge, or router, which connects to a LAN or WAN

A switch is a common device often used as a central node to connect computers or devices to a local network

Bridge: connects two networks

A Router routes data packets to the next node on the path to the final destination

A repeater amplifies or regenerates signals

A modem translates communication signals from analog to digital and vice versa

A dial-up connection is a slower type of connection through modem, usually no faster than 56 Kbps

A Virtual private network (VPN) is a public network connection that creates the illusion of a private network connection

Does not require leasing of lines

Utilizes the Internet to simulate a private network that only authorized users can access

Enables the use of intranets and extranets

A protocol is a set of rules governing communication between computers

Separate protocols are designed for:

WANs

LANs

Wireless communications

Most important set of protocols for telecommunications and networks is called TCP/IP

TCP/IP (Transmission Control Protocol/ Internet Protocol) is a set of related protocols

TCP ensures packets arrive accurately and in proper order

IP ensures efficient delivery of packets from node to node

An Internet backbone is composed of highest speed channels

An IP address is a unique ID for each network device

The DNS (Domain Name System) associates a text-based host name with an IP address

A static IP address is a permanent address assigned to a device

A dynamic IP address is a temporary IP address assigned to a device for the duration of a connection

Dynamic IP addresses provide flexibility when the number of IP addresses is limited

Ethernet: LAN protocol using coaxial or Cat 5 or 6 twisted pair cable

Gigabit Ethernet: faster Ethernet connection of one Gbps or greater

IEEE 802.11: a family of wireless protocols known as Wi-Fi (Wireless Fidelity)

Supports wireless communication within 100 meters of router

802.11 subtypes support various distances and speeds up to 248 Mbps

An Access point (AP) is a connection between wireless device and a wired network

A Hotspot allows Internet access within the range of equipment

Encryption is a function of protocols that scrambles and encodes messages for privacy

Encryption keys are shared only between sender and receiver

Bluetooth allows devices to communicate within 10 meters

Transmits voice and data

Bluetooth is considered a PAN technology

Worldwide Interoperability for Microwave Access (WiMAX) increases the range and speed of wireless communication

Works with metropolitan area networks (MANs)

Would enable Internet connection while in a moving vehicle

Long-Term Evolution (LTE) is a standard method of wireless communications, specifically for high-speed data transmission for mobile phones

Also known as 4G LTE

There are a variety of options when subscribing to an Internet network service. Things to consider are:

Downstream speed is how fast data is received from a network

Upstream speed is how fast data can be transmitted to a network

Services with lower rates for upstream than downstream are suitable for most individuals and businesses

Television cable companies can provide Internet access through cable lines.

At residence, cable is split into TV set and computer via a bridge called a cable modem

Cable shared by all subscribers connected to the node

Communication speeds may slow during peak times and as more subscribers join the service

Digital subscriber line (DSL) enables internet access where data remains digital through the entire transmission

DSL uses telephone lines connected to a DSL bridge (DSL modem)

Transmission bit rates are closely related to the distance from telephone company’s central office

T1 and T3 lines are point-to-point dedicated digital circuits provided by telephone companies

T1 line is made up of 24 channels of 64 Kbps each

T3 line is made up of 672 channels of 64 Kbps each

T1 and T3 service is expensive

Used by universities and large companies for backbone and Internet connections

Satellite services use microwave radio transmission

The service provider installs a dish antenna that is tuned to a communications satellite

Speeds up to 45 Mbps

Satellite services used for private homes and for mobile uses such as shipping and trucking

Global positioning system (GPS) is a free satellite service that provides location information

Fixed wireless is point-to-point transmission between two stationary devices, typically between buildings

Wireless Internet service provider (WISP)

Specializes in fixed wireless service

Fixed wireless is highly modular and suitable for both rural and urban areas

Fiber to the premises connects a building to the Internet via optical fibers

Fiber to the Home (FTTH) occurs when optical fiber reaches the subscriber’s living or work space

Subscribers connect computers or LAN routers to an optical fiber socket

An Optical carrier (OC) provides services through optical fiber lines

It is expensive, and offers very high connection speeds

Provides speeds in multiples of 51.84 Mbps (the base rate bandwidth)

Typically used by:

ISPs

Providers of search engines

Content-rich or high-traffic Web sites

Broadband over Power Lines (BPL) uses electric power lines to carry digital signals

Utility companies partner with telecommunications companies to provide the service

The impact of networking technology trends such as Broadband telephony,Radio frequency identification, and the convergence of digital technologies

are likely to have a significant impact on businesses and management of information

Voice over Internet Protocol (VoIP) uses an Internet connection to conduct telephone conversations

Examples of companies offering IP telephony

Are Vonage and Comcast

Free services are offered by Skype or iCall

Voip is cost effective for businesses and homes

Experts predict a convergence of the cell phone and VoIP phone

RFID tags are tiny and need little power

Objects are embedded with tags that contain a transponder (a radio transceiver activated by a signal transmitted to it)

Tags are encoded with an electronic product code (EPC)

Readers decode data stored in tag’s memory and pass the data to a host computer

RFID technology is efficient for large companies, but expensive for smaller companies

Convergence of networking technology can be seen in many examples

Cell phones can act as Web phones using VoIP

New television sets connect to Internet, cable, and satellites concurrently

A single device can connect to several types of networks

“Smart appliances” interact with their owners

There are opportunities for businesses to provide new information services and better manage their salesforces

Portable music/video players communicate with PCs via Wi-Fi to download files and transmit to wireless earphones

Cell phones read RFID tags on products and compare prices and make purchases

Summary

Software: a collective term for computer programs

Two categories of software: system or application

Programming languages and software development tools are used to develop software

Increasing amount of software is linked to the Internet

Code written in non-machine language must be translated by compilers or interpreters

Software is a collective term for computer programs

There are two categories of software, system or application

Programming languages and software development tools are used to develop software

The Internet has been linked to increasing the amount of software.

Code written in high-level languages must be translated by compilers or interpreters

Some application programs are custom-designed; many are packaged

Office productivity tools such as word processors and spreadsheets help improve worker efficiency

Hypermedia and multimedia technology are useful for training, education, research, and business

Groupware combines hypermedia and multimedia with web technologies for collaboration

Three-dimensional geographic software helps model maps and locations

Many applications support web services and access to information on the web

The most important system software is operating systems

Open source software is distributed freely via the web

Nearly all software is licensed; SaaS is an alternative to traditional software licensing

Ready-made software purchase decisions should evaluate many factors, e.g., suitability, ease of learning, ease of use, vendor reputation, expected quality of vendor support, etc.

Software piracy is still a significant problem

Telecommunications is communication over distance

Telecommunications technology has changed the business environment

Different media have different bandwidths

Networks are classified according to reach and complexity

A public network can be turned into a virtual private network (VPN)

Network protocols are sets of rules to which all devices on a network must adhere

The Internet adheres to the TCP/IP protocol

Wireless technologies make it easy and affordable to create wireless LANs and hotspots

Organizations and individuals have variety of choices when subscribing to networking services

As Internet links become faster, Internet telephony, also known as Voice over Internet Protocol (VoIP), is gaining in popularity

Wireless technologies support the increasingly popular RFID technologies

Much like hardware, telecommunications technologies are merging

Increasing numbers of employees now telecommute