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  1. 1. GSM TECHNOLOGY DIFFUSION IN NORTH AMERICA by Robert Sheppard, Jennifer Gardner and Sohil Thakkar
  2. 2. GSM TECHNOLOGY DIFFUSION IN NORTH AMERICA Introduction 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
  3. 3. 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 market. 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, virtually anywhere. A Closer Look at Some of the Data Applications When connecting the GSM-enabled phone to a laptop computer, there are additional 3
  4. 4. capabilities that are available. Internet 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. Mobile Fax 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 messages even 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. 4
  5. 5. 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 5
  6. 6. 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 computing. 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. 6
  7. 7. 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 data. 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
  8. 8. 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
  9. 9. simplistic replies. 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 paper. 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 9
  10. 10. 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 10
  11. 11. 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, 11
  12. 12. 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 12
  13. 13. 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 forward. 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 13
  14. 14. 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 single one. 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 14
  15. 15. 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 where 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. 15
  16. 16. 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. Conclusion 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 16
  17. 17. 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. 17
  18. 18. 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. 18
  19. 19. Works Cited "All For One, One For All." PCS Data Knowledge Site (Feb. 1998): 2 pp. Online. Internet. 27 Nov. 1999. "Pure Digital PCS Phones." Pacific Bell Wireless Nov. 1999. Online. Internet. 27 Nov. 1999. "Rental Program." Pacific Bell Wireless Nov. 1999. Online. Internet. 27 Nov. 1999. Smith, Ron. "Documentary: GSM Data in North America." PCS Data Knowledge Site May 1999. Online. Internet. 27 Nov. 1999. "VoiceStream International Handset Rental." VoiceStream Nov. 1999. Online. Internet. 27 Nov. 1999. "What is GSM?" VoiceStream Nov. 1999. Online. Internet. 27 Nov. 1999. "Who is Using Mobile Data Computing?" GSM Data Knowledge Jul. 1997. Online. Internet. 27 Nov. 1999. 19