Wireless Access Service Providers (WASPs)

 
Wireless Access Service Providers (WASPs)
Wireless Internet access and mobile services are strong forces behind the growth of the
technology market. This section introduces companies that provide users with the ability to
connect to the wireless Internet using mobile devices. These companies are known as wireless
access service providers (WASPs). We discuss the services these providers offer, pricing
plans and network coverage.
10.3.1 Cell-Phone Service Providers
The role of service providers has changed over the past few years. Due to consumer demand
and technological advances. When cell phones first became popular, consumers used them
solely for voice communications. Today, many cellular providers offer “complete” solutions
that include voice, text-messaging, e-mail and wireless-Web options.
M-Fact 10.2
Revenues from voice-related services still account for 90-95 percent of the market for wireless
access service providers. [*** J. Baigorri & K. Hays, “Easy Does It,” GSM World
Focus April 2001: 104***]. 10.2
The market for service providers is highly competitive, especially in the United States.
This section focuses on cellular providers in the U.S. market and includes a brief discussion
of international wireless service providers. International issues are discussed in Chapter 8,
International Wireless Communications.
Service providers and the calling plans they offer differ from each other primarily in
two areas— minutes of talk time and price. Talk time or air time refers to the amount of
time a user actually spends communicating on a mobile phone. Most providers divide this
talk time into categories depending on the time of day and volume of calls over the network.
Peak hours (i.e., the time of day when more users are on cell networks) are usually from 7
A.M. to 8 P.M. while off-peak hours (i.e., the time of day with less frequent network use)
are any other time including weekends. [***<www.sprintpcs.com>***]. Many
companies offer more talk time during off-peak hours than during peak hours to encourage
customers to use the networks at times when there is less traffic. Therefore, companies
price peak calls at a premium or restrict users’ minutes. Several popular service plans,
including the number of minutes offered and the monthly fee from various providers, are
overviewed in Fig. 10.4.
The United States has eight major mobile network operators. The operators vary in services
provided, compatible hardware, pricing plans, coverage area and supported technologies
(e.g., CDMA, GSM, TDMA and PCS—these are discussed in Chapter 10, Wireless
Communications Technologies). Sprint PCS (www.sprintpcs.com), Verizon Wireless
(www.verizonwireless.com), AT&T Wireless (www.att.com), MCI WorldCom
(www.mci.com), Nextel (www.nextel.com), Cingular (www.cingular.com),
VoiceStream (www.voicestream.com) and US Cellular (www.uscellular.com)
are the main mobile-market participants. Sprint PCS, Verizon, AT&T and Cingular lead in
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coverage area (i.e., the locations and number of people to which service can be provided)
and market share.
10.3.2 PDA Wireless Service
Most of the companies mentioned in Section 10.3.1 specialize in cellular communications
and provide services to cell-phone and smart-phone users. Handheld devices such as PDAs,
have different service providers—Omnisky and GoAmerica are two of the main service
providers with the largest coverage areas for handheld devices.
GoAmerica (goamerica.com) offers Web-browsing and e-mail services for wireless
devices including PDAs and two-way pagers. The Go.Web™ wireless Web browser
offers content, including news, financial information, entertainment and more from many
popular sites. Go.Web allows users to view entire Web pages rather than small sections of
content “clipped” from those pages (the concept behind Palm’s Web Clipping™—Web
Clipping is discussed in Chapter 11, Palm and Palm OS and Chapter 21, Web Clipping).
Users who want customized content can use MyGo.Web™, which allows users to access
information specific to their needs. For example, salespeople in the field can access their
product catalogs over the Internet, check for information about competitors, and send proposals
to their clients via e-mail.
GoAmerica enables business professionals to access a corporate network, monitor
competitors online and e-mail colleagues and clients. The GoAmerica-supported RIM
wireless handheld device allows salespeople to communicate using real-time, two-way text
messaging.
OmniSky (www.omnisky.com) is one of the fastest-growing wireless access service
providers for handheld devices. OmniSky supports the Handspring Visor™, the
Palm™ V, HP Jornada™ and the Compaq iPAQ platforms. Users can access e-mail, buy,
Service Provider
Example Plans
(range of minutes)
Extra Minutes Cost
(cents/minute)
Prices (dollars/
month) Note:
service contract
usually required.
Sprint PCS 180-2000 0.35-0.40 $29.99-$149.99
Verizon Wireless 150-2000 0.20-0.40 $35-$200
Cingular 100-2000 0.35 $29.99-$149.99
AT&T Wireless 450-2000 0.25-0.35 $59.99-$199.99
VoiceStream Wireless
300-1500 0.25-0.30 $39.99- $139.99
Nextel 400-2000 0.25-0.35 $59.99-$199.99
MCI Worldcom 50-2500 0.30-0.40 $19.99-$199.99
US Cellular 300-1500 0.20-0.30 $30-$100
Fig. 10.4 Cellular Service Providers and examples of rate plans available. [***H.
Bray, “Busy Signals,” The Boston Globe 12 March 2001:
C6***][***<www.sprintpcs.com>, <www.cingular.com>,
<www.nextel.com> and <www.verizonwireless.com>***]
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168 Wireless Communications Technologies I Chapter 10
sell and trade stocks online; chat with friends, family or business associates and surf the
Web from the OmniSky service. Consumers can personalize their service with the MyOmniSky
option and store information using the OmniSky OneTap™ storage service.
OmniSky offers one service plan that can be paid monthly or prepaid for a full year.
This service has no restriction on the number of minutes used or the amount of information
downloaded. Users must sign a 12-month service agreement. If a user decides to terminate
the service early, penalties may apply. OmniSky coverage is limited to parts of the East
Coast with sporadic coverage in the Midwest, South and select west-coast areas.
Other wireless service providers offering service for PDAs include Palm.net,
YadaYada™ and iPAQnet™. These packages are available to Palm devices and Compaq
iPAQ users. Palm.net is discussed in Chapter 11, Palm & Palm OS. Chapter 12, Windows
CE, Pocket PC and Stinger, examines the Compaq iPAQ and iPAQnet.
10.3.3 SMS and Other Messaging Services
Most handset manufacturers and wireless access providers are offering products and services
that incorporate the capability to send text messages via cell phones over the Internet.
[***M. McKay, “Pager Industry in Crisis as Customers Turn to Cellular Phones,”
The Record 25 April 2001***] In 1998, text-based messaging from cell phones became
popular in the form of Short Messaging Service (SMS) in Europe and Asia.
M-Fact 10.3
According to the Wireless Review, in one month alone in the year 200, over 15 billion messages
were sent and 200 billion total messages are projected to be sent by the end of 2001.
[***S. Marwaha, “Will Success Spoil SMS?,” Wireless Review 15 March 2001:
107***]. 10.3
SMS runs over GSM networks which are not as widespread in the United States as
they are internationally. However, many of the wireless access service providers listed in
Fig. 10.4, have their own version of messaging services (Fig. 10.5). GSM is discussed in
Chapter 10, Wireless Communications Technologies II.
service provider
Text-based messaging
service Price
Sprint PCS Wireless Web Messaging 30 for $1.99/month or 200 for
$9.99/month
Verizon Wireless Mobile MessengerSM 0.02 cents per message
received, 0.10 cents per message
sent
Cingular Interactive messaging 0.10 cents per message
AT&T Wireless 2-way text messaging 0.10 cents per message
Fig. 10.5 Messaging services offered from the four largest WASPs.
[***<www.sprintpcs.com>, <www.cingular.com>,
<www.verizonwireless.com> and <www.att.com>***].
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Text-based messaging and SMS afford many opportunities for message-based services
including advertising, m-commerce and location-based services. The future of messaging
will include not only text-based messages but interactive, multimedia messages as well.
Enhanced Message Service (EMS) includes small images, sounds, animations and text.
Multimedia Messaging Service (MMS) includes text, sounds, images, video and multimedia
information. [***S. Marwaha, “Will Success Spoil SMS?,” Wireless Review 15 March
2001: 108.***]. M-commerce is discussed in Chapter 2, m-Business, and location-based
services are explored in Chapter 3, Location-Based Services.
10.3.4 Wireless Web and Other Wireless Services
In Section 10.2.4, Convergence Devices, we discussed the development of products that
encompass the communication services available on the market today including voice capabilities,
text-based messaging, e-mail and wireless Internet access. WASPs have had to
adapt services for these new devices. Many service providers offer packages that combine
all three for one price, or each service can be purchased separately. For example, Sprint-
PCS’s Total Digital Solutions™ includes wireless Web access, Sprint’s Wireless Web
Messaging, e-mail and phone service. Verizon and Cingular have similar packages available.
The four largest wireless Web services worldwide are listed in Fig. 10.6.
M-Fact 10.4
Wireless subscribers for all wireless services are estimated to grow to 1 billion users by the
end of 2001. However, the majority of subscribers will use the service for voice calls.
[***L. Frank, “Untangling the World of Wireless Messaging,” Wireless Design & Development
March 2001: 64***]. 10.4
M-Fact 10.5
According to a recent study by the Yankee Group, the number of people using the wireless
Web will increase to over 40 million by 2002 and over 200 million by 2005. [***M. Cleary,
“Content Sites Vie for Wireless,” Interactive Week 31 July 2000: 42.***] 10.5
10.4 Networks
The corporate world is embracing wireless communications as a means of increasing employee
productivity. Many corporations, businesses, colleges and universities are building
wireless networks to allow users to access their information anytime from almost any-
Wireless Web Service Service Provider, Country
KDDI Web Messaging Service KDDI, Japan
BT Genie British Telcom, UK
Sprint PCS Wireless Web Sprint PCS, United States
i-mode NTT DoCoMo, Japan
Fig. 10.6 Largest wireless-Web services (and their providers) in the world.
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170 Wireless Communications Technologies I Chapter 10
where. In the following sections, we examine many key types of wireless networking technologies.
10.4.1 Fixed Wireless
The term fixed wireless may seem like a contradiction in terms, but fixed wireless is nevertheless
an important emerging area of wireless communications. Fixed wireless refers to
mobile devices or computers that are connected without wires in a fixed or permanent location.
[***<www.webopedia.com>***].
M-Fact 10.6
Fixed Wireless could be used by as much as 15 percent of 46.7 million broadband households
in North America by 2005. [***C. Mason, “Nokia’s Leppa Sees Technology Choices in
Broadband Wireless,” Broadband Wireless Business March 2001: 16.***]. 10.6
There are three terms used to describe communications in networks including fixed
wireless networks—point-to-point, point-to-multipoint and multipoint-to-multipoint. The
points refer to the stations, devices or networks sending or receiving signals. Point-to-point
transmission occurs when a network transmits from a central base station (station or network
which is designed to handle and route signal traffic) and sends a signal to one other
point, usually a single machine or device such as a computer in an office. Point-to multipoint
refers to communication between one central base and many users (e.g., an entire
office or area of homes). Multipoint-to-multipoint access (also known as mesh) occurs
when multiple base stations send numerous signals to multiple users or locations. [***C.
Mason, “Nokia’s Leppa Sees Technology Choices in Broadband Wireless,” Broadband
Wireless Business March 2001: 16***].
These communications are used in two types of fixed wireless technologies, Local
Multipoint Distribution Service (LMDS) and Multichannel Multipoint Distribution Service
(MMDS). LMDS uses a point-to-multipoint structure to transmit two-way (send and
receive) super-high frequency (216MHz-600MHz) signals over a broadband network.
[***C. Smith, Wireless Telecom FAQs, McGraw Hill (Columbus, OH)***] LMDS
signals are low-powered and can cover a three-mile radius. It is used primarily in small-to
medium-sized businesses. LMDS operates only when nothing is blocking the transmission
(e.g., buildings, towers, etc.); this is also known as a clear line of sight. This type of fixed
wireless supports data speeds of 155 Kbps; its largest providers are Advanced Radio
Telcom, Teligent (www.teligent.com), Winstar (www.winstar.com) and XO
Communications (www.xo.com).
MMDS uses ultra-high frequency signals to communicate over broadband networks.
As the name implies, MMDS uses multiple channels to carry signals to numerous points
(multipoint-to-multipoint). These signals are higher-powered than those of LMDS. It has a
service area of 35-50 miles and can be used to provide service to residential areas. MMDS
has higher transmission speeds and does not require a clear line of sight for communications.
In addition, MMDS is one of the few to use Orthogonal Frequency Division Multiplexing
(OFDM). OFDM is discussed in detail in Chapter 10, Wireless Communications
Technologies.
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10.4.2 Networks (WLANs, WWANs and WPANs)
Before wireless communications, wires were needed to connect mice, keyboards and monitors
to computers. Networking wires also connect terminals and printers to servers. Most
companies have established Local Area Networks (LAN) or Wide Area Networks (WAN) using
wired technology. These are two types of networks designed to connect users to a central
server (or servers) to share information across workstations and with other businesses.
LANs and WANs are built with wires and cables that connect every machine in an office
to the information servers and to the company Intranet or Internet. This has been an effective
way of sharing information, but as technology has developed, the business world is
shifting to technology with a focus on mobility.
Many companies, residential areas and service providers are seeking alternate ways of
establishing networks that can provide Internet and Intranet access without wires. These
networks include Wireless Local Area Networks (WLANs), Wireless Wide Area Networks
(WWANs) and Wireless Personal Area Networks (WPANs) that transmit and receive data
through the air. In this section, we discuss each type of network, how it operates and its
advantages and disadvantages.
Wireless Local Area Networks (WLANs), (e.g., Wireless Ethernets), have become an
inexpensive and easy method of providing high-speed Internet access to heavily populated
areas as compared to running wires and cables to each individual house or building.
WLANs are popular in manufacturing, health care, retail and wholesale industries as well
as colleges and universities. [***M. Edwards, “Mobile Internet Users Revitalize
WLANs,” Communication News April 2001: 85***]. WLANs provide coverage to
users within the area the size of an average college campus or office complex.
WLANs can be built to use either peer-to-peer communications or through access
points. Wireless peer-to-peer communication (Fig. 10.7) occurs when one device such as a
computer communicates directly with another device in a network without the use of wires.
Access points (Fig. 10.7) are gateways (entrance points) that are established at certain
points in the network. These specified points allow users to access the network and communicate
with servers that serve other users in the network as well. [***A. Leon-Garcia
and I. Widowed, Communication Networks, Mc Graw Hill (Columbus, OH)***].
Businesses use access points for employee access to the company networks and databases.
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172 Wireless Communications Technologies I Chapter 10
Colleges use access points to allow students to access the Internet from almost anywhere
on campus (see Wireless Andrew Feature).
Fig. 10.7 Wireless peer-to-Peer communication and access point WLAN network
design. [***Permission requested from Tsunami Wireless LANs
<www.tsunami.net> 05-14-2001.***].
A disadvantage of WLANs is a lack of a unifying standard, a problem shared by many
areas in wireless technology development. The first WLAN standard, called 802.11, was
developed in 1997. In 1999, the Institute of Electrical and Electronic Engineers (IEEE), a
support body for unification and development of technology standards, passed the 802.11b
standard which operates on the 2.4GHz band and is designed to support data speeds of 11
Megabits per second (Mbps)—a common measurement of data transmission speeds. Due
to interference problems on the 2.4GHz spectrum, four additional standards are under
development for WLANs—802.11a, 802.11e, 802.11g and HiperLAN/2. In addition, the
current 802.11b standard lacks sufficient security protocols and network users are
demanding higher data speeds.
Designed to extend 802.11b, 802.11g supports a faster data rate of 22Mbps. The
802.11a standard uses the 5GHz band to increase speeds to 54Mbps. The 5GHz band has
more channels and is at a higher frequency which allows for faster data rates. However, it
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©Copyright 2001 Deitel and Associates Inc. All Rights Reserved
supports a shorter transmission range (the distance between two communication points).
[***J. Cox, “High-speed Wireless LANs Are Coming,” Network World 9 April 2001:
22.***]. Intended to be the first universal WLAN standard compatible with all the 802.11
standards, 802.11e adds multimedia capabilities to data transmission and performance
guidelines. [***G. Parks, “802.11e Makes Wireless Universal,” Network World 12
March 2001: 51.***].
HiperLan/2 is a standard developing in Europe and uses the 5GHz channel. It is
designed to reach speeds similar to 802.11a (54Mbps) and uses OFDM technology. For
more information visit www.hiperlan2.org. OFDM is explained in Chapter 10, Wireless
Communications Technologies Part II.
WLANs and other networks use two spread-spectrum (i.e., spreading signals over
numerous frequencies) technologies—Direct Sequence Spread Spectrum (DSSS) and Frequency
Hopping Spread Spectrum (FHSS). DSSS divides the frequency spectrum into 14
22-MHz channels. This allows 14 WLANs to be established in the same area, and it spreads
the signals over the 22 MHz bandwidth. [***A. Zeichick, “Wireless LANs Explained,”
Red Herring 13 February 2001: 74.***]. When using a wireless networks, information
is coded into bits which are then converted to a sequence of eight radio signals called a chip.
Sixty-four chips are then combined and sent in a burst over the network. [***A. Zeichick,
“Wireless LANs Explained,” Red Herring 13 February 2001: 74.***]. DSSS has a
higher range than FHSS and allows for compatibility with the 802.11b standard. However,
DSSS channels can overlap and interfere with each other because they operate on or near
the same frequency in the band. [***”Wirless LANs Moving Toward the Enterprise
Mainstream,” <www.instat.com> April 2001: 3.***].
FHSS is a lower-cost radio technology and allows users to roam between access points
on different frequency channels. FHSS uses signals which hop up and down randomly over
the transmission bandwidth so interference between signals can be minimized. There are
78 hopping patterns in the United States which decreases the chance that interference will
occur as compared to using fewer hopping patterns. [***”Wirless LANs Moving
Toward the Enterprise Mainstream,” <www.instat.com> April 2001: 3.***].
FHSS is popular with business in the financial, health care and government industries.
Wireless Andrew: Carnegie Mellon University [***W.Simonds, “Wireless
Andrew: A Case Study in Wireless LANs,” Broadband Wireless Business
March 2001: 28-30.***]
Today students at hundreds of colleges and universities worldwide desire the ability to
use computers in their course work from anywhere on campus. Computing labs are often
crowded and the number of computers available to students is often in adequate. It
is not economically possible for a university to provide computer stations for all students
enrolled in the institution. In some cases, that would amount to 50,000+ computers
and the cost would be prohibitive. Therefore, many colleges and universities are
looking for ways to improve the student experience and increase access to computing
resources and course information. One such university is Carnegie Mellon University
in Pittsburgh, PA.
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174 Wireless Communications Technologies I Chapter 10
WLANs have many advantages over wired networks. They provide users with the
ability to access information from almost anywhere. WLANs are easy to install or move
because there are no wires or cables. WLANs are flexible enough to go where wires cannot
In 1994, an all-wireless local area network was proposed to connect all Carnegie
Mellon University students, professors and staff to the university computing network,
so any user could access resources at anytime from anywhere on campus, not just the
computing labs. At the time, the network was a mix of wired-based Ethernets that
allowed information to travel at speeds ranging from 10Mbps to 100Mbps.
The network, known as Wireless Andrew (named after the university’s founders
Andrew Mellon and Andrew Carnegie), began its initial coverage in 1997. It was limited
to seven buildings on campus—less than 25 percent of the campus facilities.
Today, the WLAN covers all campus buildings and 10,000 users (Fig. 10.8). Wireless
Andrew is built on the IEEE 802.11b wireless Ethernet standard and allows users to
upload and download information at speeds of up to 11Mbps. Network traffic and multiple,
simultaneous users on the system slows the network speed closer to 2Mbps. However,
this is still faster than DSL and many other network technologies.
[***W.Simonds, “Wireless Andrew: A Case Study in Wireless LANs,” Broadband
Wireless Business March 2001: 28-30.***]
Wireless Andrew was built using Lucent Technologies WaveLAN™ which uses
Direct Sequence Spread Spectrum (DSSS) technology. Users who install the necessary
software on their laptops or other computing devices can then connect wirelessly to the
network. In addition, users must register with the university computing center. Linux
and Windows CE devices (such as the Pocket PC) can also access the network, but special
software and registration is required.
Carnegie Mellon has set an example that many colleges and universities are
moving toward in the future. [***W.Simonds, “Wireless Andrew: A Case Study in
Wireless LANs,” Broadband Wireless Business March 2001: 28-30.***].
Fig. 10.8 Wireless LANs allow users to communicate among buildings on
campus.[***<www.dma.org/~moulderpa/andrew.htm>***]
[***Permission requested from www.dma.org 05-22-2001***]
Wireless Andrew: Carnegie Mellon University [***W.Simonds, “Wireless
Andrew: A Case Study in Wireless LANs,” Broadband Wireless Business
March 2001: 28-30.***]
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be placed. In addition, they are also scalable, which means that a WLAN can be shaped and
configured to fit the specific needs and applications of users. [***”What is a Wirless
LAN,” <www.proxim.com/wireless/whiteppr/whatwlan.shtml>***]
Imagine walking into Starbucks Coffee (www.starbucks.com) and ordering a
small cafe mocha along with 30 minutes of Internet access. This new vision of Starbucks
combines fixed wireless access and wireless networks. Starbucks teamed with Microsoft
(www.microsoft.com) and Compaq (www.compaq.com) to offer this added service
to Starbucks’ customers. Compaq provides the network infrastructure including servers,
laptops and Pocket PCs. The WLAN will allow users to surf the net, access corporate Intranets
and e-mail inside-store locations. The first trials are expected by late 2001.
Wireless Wide Area Networks are similar to WLANs except WWANs cover larger
areas such as entire cities or states. WWANs use cellular networks and satellites. ARDIS,
Transcomm and Metricom Ricochet provide WWAN services.
ARDIS is a WWAN service owned by Motorola. It was developed in the 1980s by
Motorola and IBM. ARDIS covers the largest 400 metropolitan areas in the United States
(80 percent of the U.S. population and 90 percent of U.S. businesses). [***P. Rysavy,
“Wide-Area Wireless Computing,” <www.networkcomputing.com> 30 September
1997.***].
RAM Mobile Data and Tardis Mobile Limited, both of the United Kingdom, merged
to form Transcomm (www.transcomm.uk.com). Transcomm uses AMPS and wireless
CDPD (packet data) technology (discussed in Chapter 10, Wireless Communications Technologies
Part II) to provide coverage to 93 percent of the United States business population
and is in use in 17 countries worldwide.[***P. Rysavy, “Wide-Area Wireless Computing,”
<www.networkcomputing.com> 30 September 1997.***].
Metricom’s Ricochet (www.metricom.com) has become a popular WWAN solution.
Metricom offers data speeds of 128 Kbps and is available in 15 major metropolitan
areas across the United States including Dallas, Los Angeles, Minneapolis St. Paul, New
York City, Philadelphia and Phoenix. Recently, Ricochet networks were able to provide
some customers with service at speeds as high as 225Mbps to 460Mbps. [***B. Brewin,
“Ricochet Wireless Faster Than Advertised,” Computerworld <www.computerworld.
com> 7 May 2001.***]. Ricochet is also in 15 airports nationwide and will be
available in 46 U.S. cities by late 2001. Ricochet is used by some colleges and universities
to provide service to students and faculty. [***<www.metricom.com>***].
Wireless Personal Area Networks (WPANs) cover a smaller area than WWANs and
WLANs. WPANs provide short-range connectivity for users in small areas (approximately
a 30-foot wide). WPANs have lower data rates and limited range but are less expensive to
implement and use less power than other types of networks (WLANs and WWANs). Bluetooth
piconets—small Intranets or Internets which use Bluetooth communication technology,
are examples of WPANs and there are other examples (see A Look to the Future
Feature). [***M. Edwards, “Mobile Internet Users Revitalize WLANs,” Communi-
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176 Wireless Communications Technologies I Chapter 10
cation News April 2001: 84.***]. Bluetooth is discussed in detail in Chapter 23, Bluetooth.