MANAGEMENT INFOIRMATION SYSTEM CHAPTER 5 AND 6

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Kenneth J. Sousa Effy Oz

MANAGEMENT

INFORMATION

SYSTEMS Seventh Edition

Chapter 6

Business Networks and

Telecommunications

Objectives

• 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

Objectives (cont'd.)

• 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

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 in Business (cont'd.)

• Telecommunications-supported improvements

– Business communication, including e-mail, voice

mail, instant messaging, faxing, file transfer,

mobile telephony, and teleconferencing

– Greater efficiency: information delivery is

immediate and not constrained by geographical

distance

– Better distribution of data: central storage with

both local and remote access

Telecommunications in Business (cont'd.)

• Improvements (cont'd.)

– 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

• 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:

– Email

– Digital cameras

– GPS

• Major advantage is mobility

Videoconferencing

• Videoconferencing: transmitted images and

speech

• Brings together conference rooms that are

thousands of miles apart

• Produces savings in multiple areas, including:

– Travel

– Lodging

– Car fleets

– Employees’ time

Wireless Payments and Warehousing

• Radio frequency identification (RFID):

– Enables rapid transactions and payments

– Used at gas stations for payment at pump

– Used in vehicles for automatic road toll payment

– Used to track and locate items in warehouses

• Near-field communication (NFC): a standard

communication protocol to create a radio

connection between two devices

– Mobile payment

– Electronic wallet © Cengage Learning 2015 10

Peer-to-Peer File Sharing

• Peer-to-peer (P2P) file sharing: 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

• Increasingly fast communication 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

Bandwidth and Media

• 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

• 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

Figure 6.1 Transmission speed measurement units © Cengage Learning 2015

Media

• 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

Media (cont'd.)

• Twisted pair cable: pairs of insulated copper

wires twisted together

– Flexible, reliable, and low cost

– Connects devices with RJ-45 plug-in connector

• Coaxial cable: for cable television transmission

– Used for Internet connections via cable

• Optical fiber: uses light to represent bits

– Not susceptible to EMI (electromagnetic

interference)

– Can carry signals for long distances © Cengage Learning 2015 18

Media (cont'd.)

• Radio frequency (RF) technologies: use radio

waves to carry bits

– Popular examples: Wi-Fi and Bluetooth

• Microwaves: 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

Media (cont'd.)

• Electrical power lines: electrical power grid can

be used for telecommunication

– Broadband over Power Lines (BPL) or Power

Line Communication (PLC)

• Network media acquisition considerations

– Availability

– Current and potential bandwidth

– Vulnerability to 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

Types of Networks

• Computer networks are classified by reach and

complexity

• Basic types of networks: LANs, MANs, and

WANs

• Local area networks (LAN): established by a

single organization and shared among

employees

– Server-based LAN: central server controls

communications

– Peer-to-peer LAN: no central device

Types of Networks (cont'd.)

• Wireless LANs (WLANs) offer advantages

– Easier installation

– More scalable

– More flexible: equipment is easily moved

• Scalability: ease of expanding a system

• WLAN drawback: wireless networks are less

secure than wired LANs

Types of Networks (cont'd.)

• Metropolitan area network (MAN):

– Links multiple LANs within a large city

– Uses fiber optic or wireless broadband

connections between LANs

• Wide area network (WAN): far-reaching system

of networks composed of LANs or MANs

– May be public or private

Types of Networks (cont'd.)

• Value-added networks (VANs):

– Are networks with enhanced services offered by

outside vendors

– Provide reliability, management, and

maintenance of networks for an organization

• Internet service providers (ISPs)

– Preferred method of conducting e-commerce

– Less costly than VANs

PANs

• Personal area network (PAN): 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

Networking Hardware (cont'd.)

• Router routes data packets to the next node on

the path to the final destination

• Repeater amplifies or regenerates signals

• Modem translates communication signals from

analog to digital and vice versa

• Dial-up connection: a slower type of

connection through modem, usually no faster

than 56 Kbps

Virtual Private Networks

• Virtual private network (VPN): 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

Protocols

• Protocol: 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): a set of related protocols

– TCP ensures packets arrive accurately and in

proper order

– IP ensures efficient delivery of packets from node

to node

• Internet backbone: highest speed channels

• Host: a computer connected directly to a

backbone

• IP address: unique ID for each network device

TCP/IP (cont'd.)

• DNS (Domain Name System): associates a

character-based name with an IP address

• Static IP address: a permanent address

assigned to a device

• Dynamic IP address: temporary IP number

assigned to a device for the duration of the

connection

– Provides flexibility when the number of IP

addresses is limited

Ethernet

• Ethernet: LAN protocol using coaxial or Cat 5 or

6 twisted pair cable

• Gigabit Ethernet: faster Ethernet connection of

one Gbps or greater

Wireless Protocols

• 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

• Access point (AP): connection between

wireless device and a wired network

– Hotspot allows Internet access within range of

equipment

Figure 6.3 An example of a home using a wireless network © Cengage Learning 2015

Wireless Protocols (cont'd.)

• Encryption: function of protocols that scrambles

and encodes messages

– Encryption keys are shared only between sender

and receiver

• Bluetooth allows devices to communicate within

10 meters

– Transmits voice and data

– Considered a PAN technology

Wireless Protocols (cont'd.)

• 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): a standard method

of wireless communications, specifically for high-

speed data transmission for mobile phones

– Also known as 4G LTE

Figure 6.4 How a WiMAX network works © Cengage Learning 2015

Figure 6.5 Wireless networking protocols © Cengage Learning 2015

Generations in Mobile Communications

• Networking professionals refer to generations of

mobile communication technologies

– First generation (1G): analog

– Second generation (2G): provided digital voice

encoding

– Third generation (3G): increased speeds that

support video, videoconferencing, and full

Internet access

– Fourth Generation (4G): digital only, with packet

switching and tighter security

Internet Networking Services

• Variety of options when subscribing to network

services

• Downstream: speed of receiving from network

• Upstream: speed of transmitting to network

• Services with lower rates for upstream than

downstream are suitable for most individuals

and businesses

Figure 6.6 Typical features and costs of Internet services © Cengage Learning 2015

Cable

• Internet links provided by television cable firms

• Cable connected to Internet server

• 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)

• Digital subscriber line (DSL): data remains

digital through entire transmission

• Uses telephone lines connected to DSL bridge

(DSL modem)

• Transmission bit rates

– Closely related to distance from telephone

company’s central office

T1 and T3 Lines

• T1 and T3 lines: 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

• Satellite services use microwave radio

transmission

• Service provider installs dish antenna that is

tuned to a communications satellite

• Speeds up to 45 Mbps

• Used for private homes and for mobile uses

such as shipping and trucking

• Global positioning system (GPS): a free satellite

service that provides location information

Fixed Wireless

• Fixed wireless: point-to-point transmission

between two stationary devices, typically

between buildings

• Wireless Internet service provider (WISP)

– Specializes in fixed wireless service

• Highly modular

• 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)

– Optical fiber reaches the subscriber’s living or

work space

• Subscribers connect computers or LAN routers

to an optical fiber socket

Optical Carrier

• Optical carrier (OC) provides services through

optical fiber lines

– Expensive

– Very high connection speeds

• Provides speeds in multiples of 51.84 Mbps (the

base rate bandwidth)

• Typically used by:

– ISPs

– Providers of search engines

Broadband over Power Lines (BPL)

• 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 Technologies

• Trends likely to have a significant impact on

businesses and management of information

– Broadband telephony

– Radio frequency identification

– Convergence of digital technologies

Broadband Telephony

• Voice over Internet Protocol (VoIP): uses

Internet connection to conduct telephone

conversations

• Examples of companies offering IP telephony

– Vonage and Comcast

• Free services offered by Skype or iCall

• Cost effective for businesses and homes

• Experts predict convergence of cell phone and

VoIP phone

Radio Frequency Identification

• 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 electronic product code

(EPC)

• Readers decode data stored in tag’s memory

and pass the data to a host computer

• Efficient for large companies, but expensive for

smaller companies

Converging Technologies

• Convergence occurs in networking technology

• Cell phones can act as Web phones using VoIP

• New television sets will connect to Internet,

cable, and satellites concurrently

• Single device to connect to any type of network

• “Smart appliances” interact with their owners

• Opportunities for businesses to provide new

information services and better manage the

salesforce

Converging Technologies (cont’d.)

• 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

– Compare prices and make purchases

Summary

• 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

• Public network can be turned into a virtual

private network (VPN)

Summary (cont'd.)

• 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

Summary (cont'd.)

• Wireless technologies support the increasingly

popular RFID technologies

• Much like hardware, telecommunications

technologies are merging

• Increasing numbers of employees now

telecommute