The network access technologies include voip uc and iptv

7 CHAPTER

Networks: Mobile Business

CHAPTER OUTLINE

SECTION 7.1 Connectivity: The Business Value of a Networked World

SECTION 7.2 Mobility: The Business Value of a Wireless World

Overview of a Connected World

Benefits of a Connected World

Challenges of a Connected World

Wireless Network Categories

Business Applications of Wireless Networks

What’s in IT for me?

The pace of technological change never ceases to amaze. Kindergarten classes are now learning PowerPoint and many elementary school children have their own cell phones. What used to take hours to download over a dial-up modem connection can now transfer in a matter of seconds through an invisible, wireless network connection from a computer thousands of miles away. We are living in an increasingly wireless present and hurtling ever faster toward a wireless future. The tipping point of ubiquitous, wireless, handheld, mobile computing is approaching quickly.

As a business student, understanding network infrastructures and wireless technologies allows you to take advantage of mobile workforces. Understanding the benefits and challenges of mobility is a critical skill for business executives, regardless of whether you are a novice or a seasoned Fortune 500 employee. By learning about the various concepts discussed in this chapter, you will develop a better understanding of how business can leverage networking technologies to analyze network types, improve wireless and mobile business processes, and evaluate alternative networking options.

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opening case study

Disrupting the Taxi: Uber

Ray Markovich started driving a taxi in Chicago three years ago after shutting his struggling wireless phone store. Driving a cab wasn’t particularly gratifying or lucrative—he had to pay $400 a week just to lease his white 2011 Ford Escape. It was predictable if monotonous work. Well, there’s nothing monotonous about it now. In June, Markovich, a thin, well-dressed man with short brown hair and spots of gray in his mustache and goatee, walked into the local office of Uber, the San Francisco-based taxi technology start-up. Uber put him through an hour of orientation, gave him a free iPhone that carries its car dispatch app and some gear to mount it on the windshield, and sent him on his way.

Since then, Markovich has had to dodge flak from traditional cabbies who complain that they can no longer pick up riders in the city’s tonier neighborhoods, and he’s receiving a constant flood of emails from Uber itself, offering steep discounts on new cars and other perks to secure his loyalty. At the same time, he has increased his earnings by about 20 percent and says he’s simply evolving along with his customers. “No one under the age of 40 with a smart phone is going out and getting a cab anymore,” says Markovich. “I say if you can’t beat ’em, join ’em.”

A battle for the future of transportation is being waged outside our offices and homes. Uber and a growing collection of well-funded start-ups, such as the ride-sharing service Lyft, are trying to make getting a taxi as easy as booking a reservation on OpenTable or checking a price on Amazon—just another thing you do with your smart phone. Flush with Silicon Valley venture capital, these companies have an even grander ambition: they want to make owning a car completely unnecessary. They’re battling each other, city regulators, entrenched taxi interests, and critics who claim they are succeeding only because they run roughshod over laws meant to protect public safety. “Being out in front of the taxi industry, putting a bull’s-eye on our back, has not been easy,” says Travis Kalanick, the 37-year-old chief executive of Uber. “The taxi industry has been ripe for disruption for decades. But only technology has allowed it to really kick in.”

Nearly four years ago, Uber introduced the idea of allowing passengers to book the nearest town car by smart phone and then track the vehicle on a map as it approaches their location. After the ride, the service automatically compensates the driver from the customer’s preloaded credit card—no awkward tipping required. It’s a simple experience and a much more pleasant way to get a ride than stepping onto a busy street and waving at oncoming traffic.

Uber has raised $307 million from a group of backers that include Google Ventures, Google’s investment arm, and Jeff Bezos, the founder of Amazon. It operates in 270 cities around the world and was on track to book more than $1 billion annually in rides in 2013, according to financial information that leaked to the gossip website Valleywag last November. In February alone, Uber expanded to Dubai; Honolulu; Lyon; Manila; Milwaukee; Pittsburgh; Tucson, Arizona; and Durban, South Africa.

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In the process, Uber has managed to become one of the most loved and hated startups of the smart phone age. Its customers rave about the reliability and speed of the service even as they bitterly complain about so-called surge pricing, the elevated rates Uber charges during hours of high demand. Uber has also been blocked from operating in several markets by regulators out to protect the interests of consumers or entrenched incumbents, depending on whom you ask. After customers complained about the ban in Austin, Texas, the Austin City Council adopted a regulatory structure for ridesharing, enabling Uber to operate in the city. In Boston and Chicago, taxi operators have sued their cities for allowing unregulated companies to devalue million-dollar operating permits. Things grew especially heated recently in Paris when incensed taxi drivers shut down highway exits to the main airports and gridlocked city traffic.

Kalanick calls the cab industry a “protectionist scheme.” He says these protests are not about the drivers but cab companies “that would prefer not to compete at all and like things the way they are.”

His opponents are equally critical. They accuse Uber of risking passengers’ lives by putting untested drivers on the road, offering questionable insurance, and lowering prices as part of a long-term conspiracy to kill the competition, among other alleged transgressions. Fueling the anti-Uber cause is the tragic case of a 6-year-old girl in San Francisco who was struck and killed by an Uber driver. “Would you feel comfortable if you had a 21-year-old daughter living alone in the city, using a smart phone app to get in a vehicle for hire, and that vehicle ends up being a 2001 Chevy Astro van with 300,000 miles on it?” says Trevor Johnson, one of the directors of the San Francisco Cab Drivers Association. “I’ve made it my personal mission to make it as difficult as possible for these guys to operate.”

Kalanick calls himself the perfect man for the job of liberating drivers and riders. His previous company, video-streaming start-up Red Swoosh, was well ahead of its time, and Kalanick limped along for years taking no salary before selling it to Akamai Technologies in 2007 for a modest sum. “Imagine hearing ‘no’ a hundred times a day for six years straight,” he says. “When you go through an experience like that, you are sort of a hardened veteran. You only persevere if you are really hard-core and fight for what you believe in. 1

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section 7.1

Connectivity: The Business Value of a Networked World

LEARNING OUTCOMES

7.1Explain the five networking elements creating a connected world.

7.2Identify the benefits and challenges of a connected world.

OVERVIEW OF A CONNECTED WORLD

LO 7.1: Explain the five networking elements creating a connected world.

Computer networks are continuously operating all over the globe, supporting our 24/7/365 always-on and always connected lifestyles. You are probably using several networks right now without even realizing it. You might be using a school’s network to communicate with teachers, a phone network to communicate with friends, and a cable network to watch TV or listen to the radio. Networks enable telecommunications or the exchange of information (voice, text, data, audio, video). The telecommunication industry has morphed from a government-regulated monopoly to a deregulated market in which many suppliers ferociously compete. Competing telecommunication companies offer local and global telephony services, satellite service, mobile radio, cable television, cellular phone services, and Internet access (all of which are detailed in this chapter). Businesses everywhere are increasingly using networks to communicate and collaborate with customers, partners, suppliers, and employees. As a manager, you will face many communication alternatives, and the focus of this chapter is to provide you with an initial understanding of the different networking elements you will someday need to select (see Figure 7.1 ).

FIGURE 7.1

Networking Elements Creating a Connected World

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Network Categories

The general idea of a network is to allow multiple devices to communicate at the highest achievable speeds and, very important, to reduce the cost of connecting. How a particular network achieves these goals depends in part on how it is physically constructed and connected. Networks are categorized based on geographic span: local area networks, wide area networks, and metropolitan area networks. Today’s business networks include a combination of all three.

A local area network (LAN) connects a group of computers in close proximity, such as in an office building, school, or home. LANs allow sharing of files, printers, games, and other resources. A LAN also often connects to other LANs and to wide area networks. A wide area network (WAN) spans a large geographic area such as a state, province, or country. Perhaps the best example is the Internet. WANs are essential for carrying out the day-to-day activities of many companies and government organizations, allowing them to transmit and receive information among their employees, customers, suppliers, business partners, and other organizations across cities, regions, and countries and around the world. In networking, attenuation represents the loss of a network signal strength measured in decibels (dB) and occurs because the transmissions gradually dissipate in strength over longer distances or because of radio interference or physical obstructions such as walls. A repeater receives and repeats a signal to reduce its attenuation and extend its range.

WANs often connect multiple smaller networks, such as local area networks or metropolitan area networks. A metropolitan area network (MAN) is a large computer network usually spanning a city. Most colleges, universities, and large companies that span a campus use an infrastructure supported by a MAN. Figure 7.2 shows the relationships and a few differences among a LAN, WAN, and MAN. A cloud image often represents the Internet or some large network environment.

Although LANs, WANs, and MANs all provide users with an accessible and reliable network infrastructure, they differ in many dimensions; two of the most important are cost and performance. It is easy to establish a network between two computers in the same room or building but much more difficult if they are in different states or even countries. This means someone looking to build or support a WAN either pays more or gets less performance, or both. Ethernet is the most common connection type for wired networking and is available in speeds from 10 mbps all the way up to 10,000 Mbps (10 Gbit). The most common wire used for Ethernet networking is Cat5 (Category 5), and the connectors used are RJ45, slightly larger than the RJ11 connectors used by phones, but the same shape.

Network Providers

The largest and most important network, the Internet, has evolved into a global information superhighway. Think of it as a network made up of millions of smaller networks, each with the ability to operate independently of, or in harmony with, the others. Keeping the Internet operational is no simple task. No one owns or runs it, but it does have an organized network topology. The Internet is a hierarchical structure linking different levels of service providers, whose millions of devices, LANs, WANs, and MANs supply all the interconnections. At the top of the hierarchy are national service providers (NSPs) , private companies that own and maintain the worldwide backbone that supports the Internet. These include Sprint, Verizon, MCI (previously UUNet/WorldCom), AT&T, NTT, Level3, Century Link, and Cable & Wireless Worldwide. Network access points (NAPs) are traffic exchange points in the routing hierarchy of the Internet that connects NSPs. They typically have regional or national coverage and connect to only a few NSPs. Thus, to reach a large portion of the global Internet, a NAP needs to route traffic through one of the NSPs to which it is connected. 2

One step down in the hierarchy is the regional service provider. Regional service providers (RSPs) offer Internet service by connecting to NSPs, but they also can connect directly to each other. Another level down is an Internet service provider (ISP), which specializes in providing management, support, and maintenance to a network. ISPs vary services provided and available bandwidth rates. ISPs link to RSPs and, if they are geographically close, to other ISPs. Some also connect directly to NSPs, thereby sidestepping the hierarchy. Individuals and companies use local ISPs to connect to the Internet, and large companies tend to connect directly using an RSP. Major ISPs in the United States include AOL, AT&T, Comcast, Earthlink, and NetZero. The further up the hierarchy, the faster the connections and the greater the bandwidth. The backbone shown in Figure 7.3 is greatly simplified, but it illustrates the concept that basic global interconnections are provided by the NSPs, RSPs, and ISPs. 3

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FIGURE 7.2

Network Categories: LAN, WAN, and MAN

Network Access Technologies

Performance is the ultimate goal of any computer, computer system, or network. Performance is directly related to the network’s speed of data transfer and capacity to handle transmission. A network that does not offer adequate performance simply will not get the job done for those who rely on it. Luckily, networks can be upgraded and expanded if performance is inadequate.

We measure network performance in terms of bandwidth , the maximum amount of data that can pass from one point to another in a unit of time. Bandwidth is similar to water traveling through a hose. If the hose is large, water can flow through it quickly. Data differs from a hose in that it must travel great distances, especially on a WAN, and not all areas of the network have the same bandwidth. A network essentially has many hoses of unequal capacity connected together, which will restrict the flow of data when one is smaller than the others. Therefore, the speed of transmission of a network is determined by the speed of its smallest bandwidth.

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FIGURE 7.3

Internet Topology

A bit (short for binary digit) is the smallest element of data and has a value of either 0 or 1. Bandwidth is measured in terms of bit rate (or data rate ) , the number of bits transferred or received per unit of time. Figure 7.4 represents bandwidth speeds in terms of bit rates. Bandwidth is typically given in bits per second (abbreviated as bps) and bytes per second (abbreviated as Bps). It is important to note that these two terms are not interchangeable.

A modem is a device that enables a computer to transmit and receive data. A connection with a traditional telephone line and a modem, which most residential users had in the 1990s, is called dial-up access. Today, many users in underdeveloped countries and in rural areas in developed countries still use dial-up. It has two drawbacks. First, it is slow, providing a maximum rate of 56 Kbps. (At 56 Kbps, it takes eight minutes to download a three-minute song and more than a day to download a two-hour movie.) Second, dial-up modem access ties up the telephone line so the user cannot receive and make phone calls while online. The good news is this is not as big an issue as it once was because many people have cell phones and no longer require the telephone line for making phone calls. 4

Once the most common connection method worldwide, dial-up is quickly being replaced by broadband. Broadband is a high-speed Internet connection that is always connected. Highspeed in this case refers to any bandwidth greater than 2 Mbps. Not long ago, broadband speeds were available only at a premium price to support large companies’ high-traffic networks. Today, inexpensive access is available for home use and small companies.

The two most prevalent types of broadband access are digital subscriber lines and highspeed Internet cable connections. Digital subscriber line (DSL) provides high-speed digital data transmission over standard telephone lines using broadband modem technology, allowing both Internet and telephone services to work over the same phone lines. Consumers typically obtain DSL Internet access from the same company that provides their wired local telephone access, such as AT&T or Century Link. Thus, a customer’s telephone provider is also its ISP, and the telephone line carries both data and telephone signals using a DSL modem. DSL Internet services are used primarily in homes and small businesses.

FIGURE 7.4

Bandwidth Speeds

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DSL has two major advantages over dial-up. First, it can transmit and receive data much faster—in the 1 to 2 Mbps range for downloading and 128 Kbps to 1 Mbps for uploading. (Most high-speed connections are designed to download faster than they upload because most users download more—including viewing web pages—than they upload.) The second major advantage is that because they have an always-on connection to their ISP, users can simultaneously talk on the phone and access the Internet. DSL’s disadvantages are that it works over a limited physical distance and remains unavailable in many areas where the local telephone infrastructure does not support DSL technology. 5

Whereas dial-up and DSL use local telephone infrastructure, high-speed Internet cable connections provide Internet access using a cable television company’s infrastructure and a special cable modem. A cable modem (or broadband modem) is a type of digital modem used with high-speed cable Internet service. Cable modems connect a home computer (or network of home computers) to residential cable TV service; DSL modems connect to residential public telephone service. The ISP typically supplies the cable and DSL modems. Cisco Systems is one of the largest companies producing computer networking products and services, including the Linksys brand of networking components. Typically, broadband or high-speed Internet service has an average transfer rate 10 times faster than conventional dial-up service. Telecommuting (virtual workforce) allows users to work from remote locations, such as home or a hotel, using high-speed Internet to access business applications and data.

Unlike DSL, high-speed Internet cable is a shared service, which means everyone in a certain radius, such as a neighborhood, shares the available bandwidth. Therefore, if several users are simultaneously downloading a video file, the actual transfer rate for each will be significantly lower than if only one person were doing so. On average, the available bandwidth using cable can range from 512 Kbps to 50 Mbps for downloading and 786 Kbps for uploading.6

Another alternative to DSL or high-speed Internet cable is dedicated communications lines leased from AT&T or another provider. The most common are T1 lines, a type of data connection able to transmit a digital signal at 1.544 Mpbs. Although this speed might not seem impressive, and T1 lines are more expensive than DSL or cable, they offer far greater reliability because each is composed of 24 channels, creating 24 connections through one line. If a company has three plants that experience a high volume of data traffic, it might make sense to lease lines for reliability of service.7

A company must match its needs with Internet access methods. If it always needs high bandwidth access to communicate with customers, partners, or suppliers, a T1 line may be the most cost-effective method. Figure 7.5 provides an overview of the main methods for Internet access. The bandwidths in the figure represent average speeds; actual speeds vary, depending on the service provider and other factors such as the type of cabling and speed of the computer.8

Broadband over power line (BPL) technology makes possible high-speed Internet access over ordinary residential electrical lines and offers an alternative to DSL or high-speed cable modems. BPL works by transmitting data over electrical lines using signaling frequencies higher than the electrical (or voice in the case of DSL) signals. BPL allows computer data to be sent back and forth across the network with no disruption to power output in the home. Many homeowners are surprised to learn that their electrical system can serve as a home network running speeds between 1 and 3 Mbps with full Internet access. Unfortunately, limitations such as interference and availability have affected BPL’s popularity.

FIGURE 7.5

Types of Internet Access

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Network Protocols

A packet is a single unit of binary data routed through a network. Packets directly affect network performance and reliability by subdividing an electronic message into smaller, more manageable packets. Standard packet formats include a packet header, packet body containing the original message, and packet footer. The packet header lists the destination (for example, in IP packets the destination is the IP address) along with the length of the message data. The packet footer represents the end of the packet or transmission end. The packet header and packet footer contain error-checking information to ensure that the entire message is sent and received. The receiving device reassembles the individual packets into the original by stripping off the headers and footers and then piecing together the packets in the correct sequence. Traceroute is a utility application that monitors the network path of packet data sent to a remote computer. Traceroute programs send a series of test messages over the network (using the name or IP address) until the last message finally reaches its destination. When finished, traceroute displays the path from the initial computer to the destination computer. A proxy is software that prevents direct communication between a sending and receiving computer and is used to monitor packets for security reasons.

A protocol is a standard that specifies the format of data as well as the rules to be followed during transmission. Computers using the same protocol can communicate easily, providing accessibility, scalability, and connectability between networks. File transfer protocol (FTP) is a simple network protocol that allows the transfer of files between two computers on the Internet. To transfer files with FTP, the FTP client program initiates a connection to a remote computer running FTP server software. After completing the connection, the client can choose to send and/or receive files electronically. Network access technologies use a standard Internet protocol called transmission control protocol/Internet protocol (TCP/IP) , which provides the technical foundation for the public Internet as well as for large numbers of private networks. One of the primary reasons for developing TCP/IP was to allow diverse or differing networks to connect and communicate with each other, essentially allowing LANs, WANs, and MANs to grow with each new connection. An IP address is a unique number that identifies where computers are located on the network. IP addresses appear in the form of xxx.xxx.xxx.xxx, though each grouping can be as short as a single digit.

TCP (the TCP part of TCP/IP) verifies the correct delivery of data because data can become corrupt when traveling over a network. TCP ensures that the size of the data packet is the same throughout its transmission and can even retransmit data until delivered correctly. IP (the IP part of TCP/IP) verifies that the data are sent to the correct IP address, numbers represented by four strings of numbers ranging from 0 to 255 separated by periods. For example, the IP address of www.apple.com is 97.17.237.15.

Here is another way to understand TCP/IP. Consider a letter that needs to go from the University of Denver to Apple’s headquarters in Cupertino, California. TCP makes sure the envelope is delivered and does not get lost along the way. IP acts as the sending and receiving labels, telling the letter carrier where to deliver the envelope and who it was from. The Postal Service mainly uses street addresses and zip codes to get letters to their destinations, which is really what IP does with its addressing method. Figure 7.6 illustrates this example. However, unlike the Postal Service, which allows multiple people to share the same physical address, each device using an IP address to connect to the Internet must have a unique address or else it could not detect which individual device a request should be sent to.

One of the most valuable characteristics of TCP/IP is how scalable its protocols have proven to be as the Internet has grown from a small network with just a few machines to a huge internetwork with millions of devices. Although some changes have been required periodically to support this growth, the core of TCP/IP is the same as it was more than 25 years ago. 9 Dynamic Host Configuration Protocol (DHCP) allows dynamic IP address allocation so users do not have to have a preconfigured IP address to use the network. DHCP allows a computer to access and locate information about a computer on the server, enabling users to locate and renew their IP address. ISPs usually use DHCP to allow customers to join the Internet with minimum effort. DHCP assigns unique IP addresses to devices, then releases and renews these addresses as devices leave and return to the network.

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APPLY YOUR KNOWLEDGE

BUSINESS DRIVEN DISCUSSION

Net Neutrality

Net neutrality—the great debate has been raging for some time now, with the battle lines clearly drawn. Net neutrality is about ensuring that everyone has equal access to the Internet. It is the founding principle that all consumers should be able to use the Internet and be free to access its resources without any form of discrimination.

On one side of the debate are the ISPs, such as Comcast, that are building the Internet infrastructure and want to charge customers relative to their use, namely, the amount of bandwidth they consume. The ISPs argue that more and more users accessing bandwidth-intense resources provided by the likes of YouTube and Netflix place huge demands on their networks. They want Internet access to move from a flat-rate pricing structure to a metered service.

On the other hand, content providers, such as Google, support the counterargument that if ISPs move toward metered schemes, this may limit the usage of many resources on the Internet such as iTunes and Netflix. A metered service may also stifle the innovative opportunities the open Internet provides.

The U.S. Court of Appeals for the District of Columbia Circuit struck down the Federal Communications Commission’s net neutrality rules, which would have required Internet service providers to treat all Web traffic equally. The ruling will allow ISPs to charge companies such as Netflix and Amazon fees for faster content delivery.

Do you agree that the government should control the Internet? Should website owners be legally forced to receive or transmit information from competitors or other websites they find objectionable? Provide examples of when net neutrality might be good for a business and when net neutrality might be bad for a business. Overall, is net neutrality good or bad for business? 10

If there is one flaw in TCP/IP, it is the complexity of IP addresses. This is why we use a domain name system (DNS) to convert IP addresses into domains, or identifying labels that use a variety of recognizable naming conventions. Therefore, instead of trying to remember 97.17.237.15, users can simply specify a domain name to access a computer or website, such as www.apple.com . Figure 7.7 lists the most common Internet domains. 11

The list of domain names is expected to expand in the coming years to include entities such as .pro (for accountants, lawyers, and physicians), .aero (for the air-transport industry), and .museum (for museums). The creation of an .xxx domain was recently approved for pornographic content. Countries also have domain names such as .au (Australia), .fr (France), and .sp (Spain).

FIGURE 7.6

Example of TCP/IP

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FIGURE 7.7

Internet Domains

Websites with heavy traffic often have several computers working together to share the load of requests. This offers load balancing and fault tolerance, so when requests are made to a popular site such as www.facebook.com , they will not overload a single computer and the site does not go down if one computer fails. A single computer can also have several host names—for instance, if a company is hosting several websites on a single server, much as an ISP works with hosting.

Domain names are essentially rented, with renewable rights, from a domain name registrar, such as godaddy.com . Some registrars only register domain names, whereas others provide hosting services for a fee. ICANN (Internet Corporation for Assigned Names and Numbers) is a nonprofit governance and standards organization that certifies all domain name registrars throughout the world. With the certification, each registrar is authorized to register domain names, such as .com, .edu, or .org. 12