GSM TECHNOLOGY DIFFUSION IN NORTH
Robert Sheppard, Jennifer Gardner and Sohil Thakkar
GSM TECHNOLOGY DIFFUSION IN NORTH
As society moves further into the Information Age, people are becoming more and
more dependent on wireless communication systems. Some have estimated that data
communication is growing at a rate of 25% a year. Others have approximated a 40% to 50%
increase in wireless communication systems. One technology that is taking North America by
storm is GSM. It is a wireless communication system. GSM, which stands for Global System
for Mobile Communications, is a digital cellular radio network operating in over 200 countries
world-wide. It provides almost complete coverage in western Europe, and growing coverage in
the Americas, Asia and elsewhere.
Recently, the North American GSM Alliance LLC reported that in the third quarter of
1999, more than 620,000 customers signed up for GSM wireless service in Canada and the
United States, bringing the total of GSM customers in North America to about 4.8 million.
This reflects an increase of more than double the number of customers from a year ago. The
Alliance expects to reach 6 million customers in North America by the end of 1999.
GSM service providers in North America now offer commercial service in nearly 4,000
cities and towns in 46 U.S. states and four Canadian provinces. In the past 12 months, GSM
Alliance companies in the U.S. and Canada added about 2.5 million new customers, the
equivalent of adding 5 new customers a minute. With 205 million GSM customers in the
world, GSM remains the world=s overwhelming choice for digital wireless service, and is the
fastest growing, according to the Alliance. Each month, almost eight million people sign up to
GSM networks across five continents of the world. Globally, GSM customers now equal
about 50 percent of the entire world wireless market, and two-thirds of the global digital
Of special interest is the capability of the GSM network to be used for data computing.
Most people think of voice calls when they think of cellular phones. But because GSM is
digital, one can connect the GSM-enabled phone to a laptop computer and send or receive e-
mail, faxes, browse the Internet, securely access a person=s own company's LAN/intranet,
and use other digital data features including Short Messaging Service.
Because GSM uses radio frequencies, it is a wireless platform, in contrast to
technologies which require connecting one's laptop modem to a telephone outlet to use the
land-based telephone network. This means users of GSM can be fully mobile, and do wireless
data computing anywhere, without worrying about adapters, telephone jacks, cables, etc.
The unique roaming features of GSM allow cellular subscribers to use their services in
any GSM service area in the world in which their provider has a roaming agreement. That
means the phone a person uses in France could work in Germany, Australia, Finland and even
China, depending on one=s provider's roaming agreements.
GSM-enabled phones have a "smart card" inside called the Subscriber Identity Module
(SIM). The SIM card is personalized to that person and that person alone. It identifies one=s
account to the network and provides authentication, which allows appropriate billing.
The people that are most likely to benefit from this technology diffusion are business
professionals. As people become more dependent upon data communication it will become
increasingly important to be able to plug into the office network and other data systems at a
moment=s notice. Since the system is wireless, this means that one can connect with the office
at anytime, anywhere. For example, one can turn waiting time into e-mail or fax time, at the
airport, train station, the dentist's waiting room. Also, one can turn any place into a productive
work space: a hotel room, a client's office or home, the factory floor, a loading dock, a cafe table,
A Closer Look at Some of the Data Applications
When connecting the GSM-enabled phone to a laptop computer, there are additional
capabilities that are available.
Because GSM is digital network, it provides the most ubiquitous and robust wireless data
connectivity in the world. One can connect with transmission speeds of 9.6kbps and up. Simply
dial one=s Internet Service Provider and one can access the Internet.
Need to get a fax when away from the office? Just bring the GSM phone and a laptop
PC and a person can have a mobile fax machine. With GSM one can receive and send faxes from
any place there is GSM service, which means most of Europe, plus growing parts of North
America and Asia.
Secure corporate LAN Access
GSM provides solutions for securely accessing your corporate LAN. Unlike analog
cellular communications, GSM encrypts the air link and provides additional security for a person=s
confidential e-mail, faxes or files. Some GSM service providers can provide one=s company with a
direct-digital connection right from a person=s GSM network to the person=s corporate LAN.
Short Message Service
Short Message Service (SMS) is an integrated paging service that lets GSM cellular
subscribers send and receive data right on their cellular phone's LED display, up to a maximum of
160 characters. Combine this with a laptop, and a person can receive urgent e-mail, fax
notifications, news and stock quotes, all without even dialing the phone. One can receive
when she or he is making a call.
GSM networks presently operate in three different frequency ranges. These are:
GSM 900 (also called GSM) - operates in the 900 MHz frequency range and is the most
common in Europe and the world.
GSM 1800 (also called PCN or Personal Communication Network and DCS 1800) -
operates in the 1800 MHz frequency range and is found in a rapidly-increasing number of
countries including France, Germany, Switzerland, the UK, and Russia. A European
Commission mandate requires European Union members to license at least one DCS 1800
operator before 1998.
GSM 1900 (also called PCS or Personal Communication Services, PCS 1900, and DCS
1900) - the only frequency used in the United States and Canada for GSM. Note that the
terms PCS is commonly used to refer to any digital cellular network operating in the 1900
MHz frequency range, not just GSM.
As stated earlier, GSM-enabled phones have voice communication capabilities. Before the
arrival of this technology, North America used a combination of analog and digital channels for
wireless communication. Noted also, were the wireless data communication capabilities. Laptops
with modems helped to achieve some mobile data communications, and is still popular.
Participants in the Marketplace
Who are the consumers?
The GSM technology has a wide reaching consumer base. Perhaps the easiest way to determine
who the consumers of this technology are is to ask the question "Who uses mobile data
computing?" The most obvious answer to this question is the telecommuters. These workers visit
the office maybe once a week, while conducting the majority of their business from their homes or
hotel rooms. Telecommuters are "the single most important driver behind the use of mobile data
services" ("Who is Using").
There are many other types of users and organizations that benefit from the convenience of mobile
data. For example, marketing and sales support staff may require the transfer of graphic files or
presentation layouts when conducting a promotional or sales presentation on their customers'
premises. Stockbrokers or purchasers of stock may require current stock quotes when they are
mid-flight or in their cars. Even doctors benefit from mobile data computing. As more and more
patient records are entered into a giant database, doctors will be able to tap into this information
source from any place, e.g., the examination room, the operating room, or even the side of the
road. Virtually all businesses and organizations can benefit from the use of mobile data
Who are the suppliers?
One of the challenges of providing mobile data computing is to identify, validate, and
promote major regions or "footprints" where the wireless GSM technology can be used.
Identifying these areas is important because the sole the purpose behind the GSM technology is to
provide the business traveler with seamless, transparent voice and data services anywhere within
that footprint. As this paper examines only the GSM technology in North America, we will only
discuss the footprint in North America.
The North American footprint is broken down into approximately 15 active GSM
networks. These networks have developed tight bonds with each other because of the
non-overlapping, non-competitive nature of their coverage. Also, corroborating services allow
each operator to offer its customers roaming in most major cities within North America (Smith,
"GSM Data"). For the purposes of this discussion, we have selected six suppliers, whose location
represents the broad coverage area (footprint) in North America.
The first major operator is Pacific Bell Wireless, whose headquarters are located in San
Francisco. This operator covers California's major coastal cities. Pacific Bell offers its customers
GSM service via GSM-enabled phones that one buys or rents. Customers have the capacity to
access the internet/intranet, send faxes, and send/receive electronic mail.
To the north of Pacific Bell's territory lies VoiceStream, which provides coverage for
major cities like Portland, OR and Seattle, WA, as well as 10 other western and southwestern
states. VoiceStream offers its customers data with all of its rate plans. In so doing, VoiceStream
has allowed its voice customers to start using data at any time, without switching to a different
plan or requiring additional activation. This supplier also provides adequate support to customers
using data. It has issued a 1-800 number that connects its customers directly to experts in wireless
On the opposite side of the United States in New Jersey lies Omnipoint Communications.
This supplier has GSM coverage in thirteen states, including the Boston, New York, Philadelphia,
and Detroit Metropolitan Trading Areas. What sets Omnipoint apart from the other North
American operators is their location to Europe. Many vacationers and business travelers from
Europe bring their GSM-enabled phones in order to stay connected. As a result, Omnipoint has
established roaming agreements with 46 countries and expects more to follow.
To the south of New Jersey lies BellSouth Mobility DCS, which operates in North and
South Carolina, East Tennessee, and East Georgia. BellSouth gained its experience in GSM
technology from building and operating other GSM network in countries like Australia, Denmark,
Germany, India, and New Zealand. This supplier offers roaming with 27 GSM networks outside
of North America. BellSouth also supplies Bosch World phones, which support both North
American (1900MHz) and the rest of the world's (900MHz) frequencies.
The small town of West Point, Georgia houses the next supplier of the North American
footprint: Powertel. Powertel has coverage in Alabama, Florida, Mississippi, Tennessee, and
Georgia, and licenses in seven other states. Similar to other suppliers, Powertel offers GSM
service such as internet/intranet access, sending and receiving electronic mail, and faxing
capabilities via its GSM-enabled phones.
The final supplier is Aerial Communications, which is headquartered in Chicago, Illinois
and provides GSM service in the Minneapolis, Kansas City, Tampa-St. Petersburg-Orlando,
Houston, Pittsburgh, and Columbus Major Trading Areas. In addition to providing the standard
GSM service, Aerial is conducting research into developing new GSM data technologies. One of
these technologies is the General Packet Radio Service (GPRS), which will provide 100Kbps data
rates plus "instant" connectivity to the Internet.
As seen from the list above, GSM has already successfully established itself in most
metropolitan areas, even though the technology has only been in North America a few short years.
Researchers are conducting experiment to improve connectivity time, data transmission speed,
and general ease of use. The next few years should see an expansion in growth as more and more
users become aware of this remarkable technology.
What are the substitute/complement markets?
Although many manufacturers would like to claim that there are no substitutes to his
product, this is often not the case. When determining the substitutes for GSM technology, one
must look at the very nature of the technology itself. What makes GSM technology so unique is
that it not only provides its users with Internet connectivity, but that it allows this connection to
occur with no physical link. Therefore, a substitute to this market would be one's telephone line
coming into their house. Both provide data and voice capabilities, but only one provides mobility.
A second possible substitute for GSM technology would be paging. Paging allows
customers to have mobility and some plans even provide news, stock, and weather updates. One
can receive messages and in more recent paging technologies, one can even interact with
GSM technology is simply a service that various carriers can supply to their customers,
but it requires the purchase or rental of an GSM-enabled phone. Therefore, the complement
markets for this technology center around the GSM phone manufacturers, such as, Nokia,
Ericsson, Bosch, and Qualcomm, and the GSM phone rental companies, such as, Cellhire.
Who are the regulators?
Based on the nature of GSM technology, one can utilize its advantages not only locally in North
America, but anywhere GSM service is available. As this technology has worldwide capabilities,
the list of regulators becomes extensive. For the purpose of this paper, we will be focusing
primarily on the Federal Communications Commission (FCC), as they are the telecommunications
regulators for the United States. We will be discussing their role in greater detail later in the
Understanding Pricing and Incentives
How are prices set?
Customers who decide to use the GSM technology will need to either purchase an GSM-enabled
phone or they will need to rent one. The cost of buying an GSM-enabled phone ranges anywhere
from $249.00 to over $340.00 ("Pure Digital"). These phones offer many state-of-the-art features
such as an automatic network search between the GSM 900 and 1900 frequencies, data and fax
capabilities, a built-in PC card, a choice of over 20 languages, a phone book, voice messaging
service, and a clock with date and alarm functionality. These phones all come equipped with a
Subscriber Identity Module (SIM) card, which allows the network to identify and authenticate
your account, which in turn allows for appropriate billing.
The rental of an GSM-enabled phone varies depending on the location from which you are
RENTALPERIOD PHONEONLY DELIVERY FEE
Daily $6.95-$29.00 (3 day minimum) Free-$9.99
W eekly $39.95-$49.00 Included
Monthly $75.00-$149.00 Included
Loss Protection $0.99/day N/A
*(PacBell “Rental Program and (VoiceStream “International Rental”)
renting. The primary company that provides this rental service in the U.S. is Cellhire. Cellhire
bases their rates on a rental time period of daily, weekly, or monthly.
Below is a chart detailing this company's rental rates. *
Cellhire's rental costs also include the following amenities: the latest dual/tri-band phones
available, a leather case, two batteries (one standard and one high capacity), a rapid charger, a
cigarette lighter adapter, a travel adapter (compatible with user's destination), and user guides.
Once a consumer has purchased or rented a GSM-enabled phone, then service charges for
use range from about $5.00/month plus $0.15/minute airtime charge. Long distance and roaming
charges may apply depending on the nature of the use of the phone. These are U.S. prices as this
paper is only focusing on North America. International pricing may vary.
What impact do changes in prices have on the marketplace?
Given the fact that GSM technology is relatively new to North America, prices have not
changed much in the few years that the technology has been available. Although the cost of
purchasing a phone is relatively expensive and the rental process can be cumbersome, this has not
hindered the explosive growth in the North American market. In North America, GSM serves 3.6
million customers. Approximately 11 new cities go on-line each day ("What is GSM?"). Based on
the growth for 1997, GSM technology customers are growing at a rate of two every minute
(O'Grady, "All For One"). Given these statistics, one can deduce that an increase in price would
probably have little effect on the growth of the marketplace. Demand for the GSM technology
appears to be relatively inelastic, meaning that a significant change in price will not produce a
significant change in quantity. As time progresses, however, prices will eventually begin to fall,
making this technology accessible and affordable for everyone.
Given the price structure, how do the incentives for consumers change their behavior?
Since consumers have a choice between renting and purchasing an GSM-enabled phone, the
pricing incentives of these two options plays a large role in the behavior of the consumer.
Suppose that the price of purchasing an GSM-enabled phone dropped significantly. Consumers
might be more likely to purchase a phone rather than rent based on their perceived usage rates.
On the other hand, suppose that a consumer does not have an GSM-enabled phone, yet needs one
for a brief business trip to Hong Kong. The lower cost of renting a phone will prompt the
consumer to rent rather than buy. Also, by renting the consumer receives a package deal (see
above) that may cost extra to the person who is buying the phone.
How do the incentives for suppliers change their behavior?
Suppliers have much to gain whether the consumers purchase or rent GSM-enabled
phones. Supplier incentives have prompted the 15 active GSM providers of North America to join
forces under two organizations; viz., GSM North America, which is the North American interest
group for the GSM Association; and the GSM Alliance, whose charter is "to create a national
network and develop seamless wireless communications for customers, whether at home, away,
or abroad" (Smith, "GSM Data"). Why have these GSM providers formed alliances with one
another? They have joined to ensure non-competitive, non-overlapping coverage areas. This
agreement means that once a customer leaves his or her original service area, he or she is going to
incur roaming charges based on the boundaries defined by the two organizations. These roaming
charges are very profitable for the suppliers, and are virtually guaranteed due to the very nature of
the GSM technology.
How do the incentives for competitors change their behavior?
Although the market for GSM technology is experiencing explosive growth, the cost of
purchasing an GSM-enabled phone or the hassle of renting one works to the advantage of the
competitive markets. Competitors, such as local phone companies, can offer Internet service, data
and faxing capabilities, etc. for a reasonable monthly connection fee. These competitors are
investigating ways to improve their connection speeds and general quality of service in order to
maintain their stationary customers who cannot afford nor have a need for GSM technology.
O'Grady, Vaughan, ed. "All For One, One For All." PCS Data Knowledge Site (Feb.
Role of Regulators
Regulators have the distinct role of influencing the diffusion rate of a given technology.
The Federal Communications Commission (FCC) has had a direct impact on the development of
the wireless industry in the U.S. From the very beginning of wireless communication, regulators
have shaped the technological advances in the market.
Digital wireless and cellular roots go back to the 1940s when commercial mobile
telephony began. Compared to today's furious pace of development, it may seem odd that wireless
did not come along sooner. There are many reasons for that. Technology, disinterest, and to some
extent regulation limited early United States radio-telephone development. As the vacuum tube
and the transistor made possible the early telephone network, the wireless revolution began only
after low cost microprocessors and digital switching became available. And while the Bell System
built the finest landline telephone system in the world, they never seemed truly committed to
mobile telephony. Their wireless engineers were brilliant and keen but the System itself held them
back. Federal regulations also hindered many projects.
The Cellular Telecommunications Industry Association (CTIA) in 1994 began pushing
federal legislation to outlaw cloning and scanning radios that could tune in the cellular band, to
prevent by law what their industry failed to do themselves. Years behind the fraud curve
compared to GSM, the CTIA worked with the Secret Service to create a poisonous anti-cloning
and anti-hacker hysteria. Fueling these self-made flames by ridiculously inflated loss numbers, the
CTIA became a shadow arm of federal law enforcement, striking out at cloners rather than
immediately implementing authentication to prevent cloning, or creating low price companion
plans to satisfy the demand for second phones, or mild encryption to prevent easy eavesdropping.
GSM, by comparison, easily carried out authentication and encryption. According to studies,
GSM phones have never been cloned in the field, using over the air techniques.
GSM North America was formed when the GSM Memorandum of Understanding (MoU)
Association decided, because of its size, that it would be advantageous to create interest groups
for each continent or area. One of these was the North American interest group, which exist to
support the ongoing operations of GSM, especially as it relates to things that are unique to North
American regulatory environments or frequency issues, and to work on improvements going
The GSM Association was formed in 1987 as a result of the European Union's desire for
adopting common standards for cross-border mobile communication. Today, the Association has
over 340 members worldwide, consisting of telecommunication administrators, regulators, and
network operators. Members are actively engaged in promoting GSM, its application, and the
long-term establishment of global roaming among GSM-compatible networks, including the 900,
1800, and 1900 MHz frequency ranges.
Every operator that uses GSM is required to join the GSM Association. So all GSM
operators in North America by definition are part of the GSM North American interest group.
Thehe Alliance, on the other hand, is a business entity that is comprised of volunteers. Therefore
all the Alliance members belong to the MoU Association, but the opposite is not true. The driving
force for the Alliance is to come together for a common business interest. It is a corporation that
is capable of owning or building assets, and promoting different services.
The reason the landscape for digital wireless is so different in the U.S. than in Europe
where GSM technology was born, is that the U.S. wireless technology grew up into AMPS
(analog), which first went commercial in late 1983 in Chicago. When it went commercial, the
technology was by most standards at least ten years out of date, the reason being that it was
frozen way back in time through the Federal Communications Commission (FCC) regulatory
process. The FCC approved it and the U.S. used it. Nobody expected it to go through heavy
growth, but it did.
In Europe they had multiple other standards. In the mid-eighties, they looked at it and
asked, should they try to centralize on some standard? What was driving them in Europe was
roaming. They wanted to be able to go from country to country. So they created GSM to be the
standard in Europe, and it became effectively the mandated standard and as such grew up to be a
In the U.S. meanwhile, AMPS capacity was a problem. As a result, the Cellular industry
created the TDMA approach to take one analog channel and put three digital channels on it. At
the same time, the industry was approaching the FCC for additional spectrum because Cellular
was growing far faster than anyone thought it would. The FCC was hesitant on providing more
spectrum because the Cellular industry had indicated that the initial spectrum would take care of
them forever and only nearly three years later the industry had come back looking for more. The
FCC wanted to know what the industry was planning on doing to help the process. So, TDMA
was in part an engineering necessity, and to show good faith in approaching the government for
needed spectrum relief.
Also, CDMA was created with a similar idea of how to get more capacity. The U.S.
consumers benefited from having multiple technologies available, because the industry competed
not only in price and services, but also on technology.
Now, the wireless industry is headed towards third generation. Given the size of the
market, instead of trying to mandate or encourage one technology, perhaps there is a need to have
the robustness of different standards and let them compete. No one can know how the
environment is going to evolve.
The Telecommunications Act of 1996 has allowed penetration of foreign owned
companies into the U.S. markets. This policy change is perhaps the main reason why GSM
technology has taken root in North America in the last two years.
Analysis of Technology Diffusion
The diffusion of the technology is given by:
0.5 * (1+tanh (α * (t - t0 ))).
α is the measure of penetration of technology in the market.
t0 is the measure of time that would elapse for technology penetration to reach half of the
estimated total penetration.
The following equations are used to calculate α and t0:
α = β11*T + β12*D + β13*C + β14*I + β15*Co + β16*E + β17*G
t0 = β21*T + β22*D + β23*C + β24*I + β25*Co + β26*E + β27*G
G = GDP/population(in $100,000/person)
T = Telephone line penetration/population
C = Cellular penetration/population
I = Internet penetration/population
Co = Competiveness in market = 1 if yes, 0 if no.
E = Customer worldwide/pops(measure of network externalities)
D = Population density in sq. miles per 1000 people.
Values of βs:
βi1 (where i = 1 or 2): It is the independent variable indicating the fraction of population with
wireline telephones that are most likely to have GSM as well. This value should be POSTIVE
since it represents the potential demand of mobile communication with GSM.
βi2: It represents the effect of distribution of people around the geographical area. More
distribute the people are more is the need for communication and positively correlated with the
penetration of GSM.
βi3: It correlates the present penetration of other mobile technology with penetration of GSM. It
could be POSITIVE or NEGATIVE based on switching interia (higher interia has a negative
effect and vice-versa) and need for more/less mobility (higher the need for mobility in wider
geographical regions more positive is the βi3 and vice-versa.)
βi4: Internet and e-commerce are the complementary products for GSM. The more the
penetration of Internet, the more the need for people to get connected from anywhere at anytime.
Therefore Bi4 would be POSITIVE.
βi5: More competition is related to lower prices and larger coverage (penetration), hence, the
competitive market. Therefore, competition will POSITIVELY effect the penetration of GSM.
βi6: Large network externalities and global roaming incentive facilitate the penetration of GSM.
Thus this Beta should be POSITIVE.
βi7: Per Capita Income represents the ability of a person to spend on the service or services that
satisfy his/her needs. Thus, this β should be POSITIVE.
In the above equations:
A large α represents great penetration.
A small t0 represents faster penetration.
In conclusion, GSM or Global System for Mobile Communications is a cellular digital
radio system. It operates on a radio frequency, therefore, it is a wireless technology. Because of
its wide spread use of some odd 200 countries, paired with roaming agreements, GSM really is a
global technology. These roaming agreements allow customers to use the same phone when
calling someone in another country. This is made possible due to the "smart card" inside the
GSM-enabled phone, called the Subscriber Identity Module (SIM). The SIM card is
personalized to that person and that person alone. It identifies a person=s account to the
network and provides authentication, which allows appropriate billing.
Another noticeable advantage of the GSM-enabled phone is that it has several data
communication mobile features. A person can be completely mobile with the ability to send or
receive e-mail, faxes, browse the Internet, securely access his or her own company's
LAN/intranet, and use other digital data features including Short Messaging Service just by
plugging the GSM-enabled phone into a laptop computer. Even though many laptops contain
modems, they are not as versatile as a laptop with a GSM-enabled phone.
This phone will become particularly useful to business professionals as the need for
data communication increases throughout North America. Moving into the 21st Century,
more companies are becoming increasingly dependent on data communications. Also, the
world is moving in the direction of a global economy. Mergers, buyouts, among other things,
help to create new areas of centralization for the headquarters of companies and ex-patriots.
This creates a market for business travelers, which in turn creates the need for mobile
communication in voice and data.
In the third quarter of year two, GSM has reached more than 4.8 million customers in
North America, and that number is expected to reach 6 million by the end of 1999. According
to GSM operators, this growth rate has well exceeded any competing technology of its kind.
Therefore, it is assumed that t0 is relatively small, and α is relatively large for GSM-enabled
phones compared to similar wireless technology penetration in North America. The outlook
on the growth potential of GSM is that it will continue to increase.
One reason for the rapid growth of GSM in North America is due to regulators lifting
restrictions and agreeing to adopt the 3G (third generation) technology for wireless phones.
The family of 3G standards was agreed upon to form the foundation for the next generation of
wireless communications systems. These advanced wireless systems will provide high-speed
data and Internet access, full-motion video and other sophisticated multi-media services, as
well as global roaming.
In order to enter this market a company has to be approved by the GSM Alliance. Once
approved by the Alliance there is no competition between the various service providers because
each company acts for the common good of the Alliance. Barriers to enter the market is not very
high. It hinges on approval.
As the customer base grows, the price of buying the phone should decrease. Because this
is the latest-and-greatest technology of its kind, an incentive to expand the customer base would
be to reduce prices.
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