applications and we consider the possibility that mobile phone companies might re- ... Although a number of micro cellular systems are already in operation or under ... personal communication, business use of SMS has, until recently, had little ...
Electronic Commerce: The End of the Beginning 13th International Bled Electronic Commerce Conference Bled, Slovenia, June 19-21, 2000
Mobile Electronic Commerce: Reintermediation in the Payment System J. Felix Hampe
Paula M.C. Swatman
Paul A. Swatman
J. Felix Hampe, Paula M.C. Swatman, Paul A. Swatman
Abstract Rapid advances in electronic commerce and services have opened up new opportunities for businesses and organisations over the last decade. The fusion of Internet technology and applications with wireless communication marks an important further stage of progress. Applications based on mobile telecommunication infrastructure generate new models for corporate communications, both internally and externally, providing a new channel for marketing and sales. This paper summarises the current state of enabling technology for mobile telecommunications and offers an overview of applications for mobile electronic commerce. We look at the ways in which mobile phone service providers can enhance existing offerings to provide nomadic access to a wide range of applications and we consider the possibility that mobile phone companies might re-invent themselves.
Paul A. Swatman
1.
Introduction
Although the various aspects of electronic commerce enabled by the Internet are well established, the proportion of population able to use Internet Commerce via the common, web-enabled PC is still rather limited. The penetration of mobile phones, however, is significantly higher in most industrialised countries, reaching well above 50% in Scandinavia generally and, in Finland, customers between 18 and 25 years of age have uptake levels close to saturation at 95%. It is thus quite obvious that linkage of mobile phones and electronic commerce has enormous potential to increase access to electronic commerce applications. All the parties to mobile telecommunications, from the device manufactures and mobile network carriers down to the valueadded service resellers are focusing on extending their areas of activity into electronic commerce. This trend is most clearly identifiable in European, Asian and Australasian markets stemming mainly from the fact, that in these regions the rollout of modern digital cellular telecommunication infrastructures, e.g. GSM based networks, is significantly advanced compared with areas of the world, specifically the US. A discussion of this trend can be found in the link list provided by [GMCF00]. The concept of mobile electronic commerce (otherwise known as wireless commerce, mobile commerce or, as we prefer, M-Commerce) came into existence around the mid 1990’s, and resulted in the publication of very optimistic forecasts for daily transaction figures by the year 2000 [see Logi97]. The widespread acceptance and use of M-Commerce, however, is still at an early stage of development. Both the technology and the applications are maturing – and the first, really sophisticated products/applications are just beginning to be offered commercially. In this paper, we first summarise the technological infrastructure which underpins mobile telecommunications and computing and then, by means of a discussion of current and emerging applications which make use of this infrastructure, establish the existence of a sophisticated and technologically equipped user base for M-Commerce. Finally, we discuss ways in which mobile phone service providers might re-conceptualise their industry, and reengineer their businesses.
2.
Technology Infrastructure for Mobile Computing
The enabling technologies for Mobile Electronic Commerce (M-Commerce) are built around 2nd generation mobile communications networks, and use digital signalling, digital speech coding and a cellular structure. Mobile networks can be satellite-based (e.g. Iridium) or, more commonly, terrestrial. Terrestrial networks themselves fall into two categories – micro or regional cellular systems. Although a number of micro cellular systems are already in operation or under development (IETS100; IEEE00; IsDa00; Blue00), this paper concentrates on the widely-used regional networks particularly GSM, the Global System for Mobile Communication (Mouly and Pautet [1992] provide a very thorough coverage of GSM for the interested reader). Transactions between a mobile device and its GSM base transceiver station are very secure (see, for example, MoPa92:476 for an explicit description of procedures for authentication, channel encoding and the use of signatures). The mobile device itself contains a subscriber identity module (SIM) which is, in fact, a smart card – and which enables the use of a PIN for verification (see VeWe98 for a short overview of smart card technology). The SIM card provides strong security mechanisms against ‘replay’ attacks, in addition to enabling unique device identification codes. The card uses a unique challenge-response algorithm to authenticate the user – and, by extension, any transaction the user engages in. Of course, the complexity of the security issues increases once the transaction is carried beyond the mobile network on which it originated – the security of such communications must then also depend on the security features of the fixed telecommunication networks, as well as any intervening mobile networks. Clearly, linking more and more mobile communication networks 2
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together into a global meta-network will make security and trust relationships a key issue for the success of M-Commerce. It will no longer be acceptable to focus on a single, standard-based network with a single management authority (VaDe96 discuss these challenges in some detail – such a discussion is outside the scope of this paper). While the concept of data communication within GSM systems has been discussed for a number of years, it is only since the development of GSM Phase 2 in 1996, with its short message service (SMS) for sending and receiving brief text messages at 9600 bps (see Hill97 for an overview of the GSM development phases), that data transfer became possible across the mobile phone network. Yet while SMS acquired something of a cult status with young users of the GSM network for personal communication, business use of SMS has, until recently, had little acceptance. With GSM Phase 2+, however, new enhancements (either already available or soon to be rolled out) appear likely to increase the use of mobile data transfer by the business community and general populace. Convergence of the existing variety of mobile networks is the next logical step in this process. With the 3rd generation of mobile networks this goal should be reached before 2010. The emerging standard is sometimes called GSM Phase 3, but is better known (see UMTS00; ITU00; NTTD00b) as either Universal Mobile Telecommunication System (UMTS) or International Mobile Telecommunications-2000 (IMT-2000). This approach is very general and complex and is intended to integrate most of our present telecommunication networks. It promise improved bandwidth, compatibility and new service opportunities – particularly for M-Commerce, although the problem of designing adequate devices with appropriate user interfaces is still largely unresolved. Some promising new developments include: •
The SIM Application Toolkit (SAT) : this allows programming of the mobile equipment (ME) or mobile terminal (MT) through the SIM chip which, being a smart card, already has a processor with memory and application storage. Using the ME itself as an input/output device, the SIM can initiate operations and receive results on a store-and-forward basis, using the SMSC as an intermediate server (if the receiver is presently offline, an immediate delivery is initiated as soon as a connection is reestablished). In principle, given the restricted set of commands, service providers can offer the download of a wide range of application logic to their subscribers – with significant implications for customised mobile commerce;
•
General Packet Radio Service (GPRS) : another GSM Phase 2+ enhancement allows the transfer of packet data at speeds of up to 64kbps (see Lesk98 for an overview of services provided in GPRS, including TCP/IP bearer services, encryption of packet data, support of SMS over GPRS and support for packet charging). More complex mobile commerce applications are enabled by GPRS, which allows for always-on services, traffic control and basic quality of service mechanisms or ISDN interfacing. Indeed, [Lesk98] asks whether GSM plus GPRS is not already sufficient for most of the data communication applications used with mobile or personal digital assistants today. Initial connection setup time in GPRS is less than 1sec, allowing for rapid data access. [HoCo98] describe two complementary nodes which provide further enablers for M-Commerce – SGSN, the Serving GPRS Support Node and GGSN, the Gateway GPRS Support Node:•
the SGSN keeps track of the location of the mobile within its service area; and sends and receives packets from the mobile, passing them on, or receiving them from the GGSN,
•
the GGSN converts the GSM packets into other packet protocols (such as IP) and sends them out into other networks.
[HoCo98] note that: ‘GSM data provide a wealth of opportunity for transferring a variety of information to the user on the move. From simple email to video and multimedia, almost anything is possible. The future will bring even higher bandwidths, larger markets and with them lower costs. However in order to achieve the goal of mass market data use the applications must be developed with mobile in mind. Users will not want to bother with redialling just because of a dropped call, and they will not be happy to pay for two timeslots when one would suffice if only the data was pre-compressed and used an efficient transfer protocol. We need to look at the system as a whole, starting with the users needs and ending with the data transport mechanism.’
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•
Wireless Application Protocol (WAP) : polarisation of communications technology towards the Internet industry has influenced mobile communications consortia aiming to provide access to Intra- and Internet applications on mobile terminals. An initiative by Ericsson, Motorola, Nokia und Unwired Planet defined a set of open protocol standards for wireless applications which were independent of the underlying network technology. The basic architecture was based on earlier work by Unwired Planet Inc., which defined the Handheld Device Markup Language (HDML) and the Handheld Device Transport Protocol (HDTP) as proprietary solutions [Unwi98]. The work on WAP started in 1997 and today a large proportion of the mobile communications industry has joined the standardisation body, where version 1.2 of the standard is in preparation [WAPF00]. WAP-based application are independent of the type of mobile equipment, details of the user interface, the provider and the underlying network technology. In contrast to SAT, which is restricted to GSM networks, WAP offers a unique development platform for all wireless networks. WAP offers a potentially powerful platform for the development of M-Commerce applications, including the Wireless Markup Language (WML) based on a special XML document type; the Wireless Markup Language Script (WMLScript) for simpler programming [WML99]; and the Wireless Telephony Application Interface (WTA), which offers procedures for call setup, message sending, editing of the phone book etc. to be used by the program developer to run on the mobile [WAPF99].
•
New mobile appliance types: any discussion of the technological issues of mobile commerce must include the accelerating development of new kinds of mobile end-user devices. In addition to mobiles with colour displays and keyboard extensions, considerable effort has been put into the construction of personal digital assistants with built-in mobile communication interfaces (see Joke99 for an overview of PDA technology). All the major mobile equipment manufacturers, such Nokia, Ericsson, Motorola, etc. have recently launched devices with these features. A leading-edge example of integration comes from Qualcomm, who offer a Palm Pilot combined with a feature rich mobile (Qual00), although this device is not yet WAP-enabled. Prototypes of many mobile appliances are available or under development from manufacturers, who are aiming to improve screen size, resolution, colour brightness, handling via limited voice command recognition, or pen input. Other aspects, such as smaller power supplies for mobiles or separated foldable displays are underway (see, for example, Eric99). The major obstacle to the ‘perfect’ hand-held device is the existence of mutually exclusive requirements – such as restriction to palm size vs. ‘one touch’ navigation, or feature richness vs. clear conceptualisation. Resolution of these apparent incompatibilities is still a long way from fulfillment. It will take a serious research effort to provide solutions superior to those available today. While innovative, the concept of handling many different specific devices – even where these are connected by micro networks (e.g. Bluetooth) – is still just a stage in the development of the ultimate mobile communications network management strategy.
3.
Foundations of the M-Commerce Marketplace
If this technology is to lead to the development of mobile electronic commerce, there must be both the capacity to develop, as well as the demand for suitable applications. In 1997, the European Telecommunications Standards Institute published a standardisation framework for multimedia mobility in the information society [ETSI97] which demonstrates the potential for mobile electronic commerce, pointing out the need for personal as well as terminal mobility. Demand for data transfer over mobile networks is already high – and growing at an ever-increasing pace. Although the short message service (SMS) has only recently gained wide acceptance, the growing interest in instant messaging (IMPP00), reflected in the availability of free SMS distribution services via web-page interface (see MTN00), has already caused this simple and restricted form of data communication to add a significant transfer load to most GSM-networks. Even with the creation of new technologies for easier input, such as T9 instant message text input [Tegi99], however, the limitations of alphanumeric typing on a numeric keypad and 160 characters per message limits create severe restrictions for professional use of SMS. The possibilities offered by 4
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WAP, such as the ability to construct menu hierarchies with selections at each level, offer much more sophisticated applications than simple text messaging ever could. While there are a host of likely application structures, it is possible to distinguish between the following major types: Content applications: •
messaging services (notification, reading, synchronisation of message stores)
•
directory enquiries (names, numbers, parts, prices, results from web-based agents);
•
predefined database retrieval procedures (next available contract ID, balance status; service level)
•
commercial content delivery (news services; information brokerage delivery, e.g. Reuters Wireless Services [Reut99])
•
catalogue or dictionary lookup
Transaction-based applications: •
unified messaging services (replying, message forwarding, media conversion)
•
banking (transfer, last transaction, fees)
•
ticketing (cinema, theatre, sporting events, table bookings, train enquiries and seat reservations )
•
ordering (food delivery, books or CDs from list of top ten, special offers)
•
payment (online via credit card record exchange and CallerID, billing by third party collect, e.g. telecom carrier or mobile service provider)
Edutainment applications: •
games
•
joke telling
•
multiple choice knowledge questionnaires
•
horoscopes
System maintenance applications: •
user profile definition (message system configuration, call rerouting plans);
•
administration (PIN change and access rights, cost control, event tracking, logging)
•
storage management (junk filtering, ignore address lists, garbage collection, backup)
While the category examples above are not intended to be exhaustive, they do demonstrate the sort of dialogue complexity which could realistically be handled by the WAP programming paradigm. Other applications which have been suggested by more optimistic commentators (such as travel navigation systems with extensive sets of directions, distances and indications) are less feasible due to the complexity of user interaction on a numeric keypad and with the limited screens currently available – particularly in moving vehicles, ambiguity, and the long overall transaction times involved. This last argument, in particular, deserves careful consideration – handling of incomplete transactions will involve considerable effort and is wasted transfer time for all parties. M-Commerce applications with these design deficiencies will not be well accepted and are likely to be unprofitable. Some applications have been announced and some prototyping development has already been undertaken. For most GSM networks, however, the rollout of applications is not expected until the end of the year 2000 because WAP-enabled services lacking GPRS (ie. based on pure SMS) are slow and lack the ‘always on’ mode of operation. The upgrading of GPRS is scheduled to start from the end of 2000, but it will take a tremendous investment and a significant installation period to make it area-wide, let alone globally, operational. In addition to those applications already discussed, our research focuses on the generation of value-added services for specialised industrial applications. Facilities Management for larger 5
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distributed factories or office layouts is a promising field for the application of mobile technologysupporting network management, or for message handling in domotic (intelligent home) systems [Bosc00]. For example, there are significant possibilities available from linking incoming notifications to varying data sources – for example, maintenance documentation, personnel planning schedules, spare parts registers, customer contract details, etc. require efficient servicing by small, but completely mobile support groups, which can react with minimum delay and administrative overhead. Although specific value-added services of this sort are not designed for use in consumer-oriented mass markets, there is a significant proportion of small and medium enterprises having their own corporate messaging or management infrastructure in most economies. It is therefore economically feasible to design customisable solutions for M-Commerce which can be implemented in a variety of ways. These solutions will not be carrier-grade, but might be much more flexible and readily adapted to new technology. The marketplace for M-Commerce will, we suggest, be a flexible and constantly evolving one, where new applications might be developed quickly and cheaply for a single customer (or customer group) and spread across an industry sector or geographic region. The process of allowing customers to pay for services via their telephone bill is just one example of this sort of application.
A Revelatory Case – Japan’s I-Mode by NTT DoCoMo Although Japan cannot be considered a representative market for M-Commerce, the outstanding success of the I-Mode project by Japan’s leading mobile communications provider, NTT DoCoMo, suggests that mobile commerce might well gain global acceptability. In February 1999, DoCoMo launched a proprietary service for continuous connection with the Internet via mobile phones. Within a year the service had almost 4 million subscribers, with weekly growth rates approaching 150,000 new subscribers [NTTD00c]. The services on offer are a limited subset of those described above – with others, such as Karaoke, being original to I-Mode. NNT DoCoMo has announced that it will introduce third-generation mobile communications based on its W-CDMA system from the spring of 2001, making it one of the first IMT-2000 suppliers in the global marketplace. Just recently, the company announced a new M-Commerce initiative involving music sales – demonstrating its widespread range of applications and emerging distribution channels with new intermediaries [NTTD00d]. The company has formulated a very broad vision for 2010, showing strong commitment for the development of mobile infrastructure and services [NTTD98] – and, while other countries have quite different demographics (and psychographics) from the Japanese marketplace, the I-Mode system shows just what can be done, even with the limited applications currently available.
4.
The Brave New World of M-Commerce
In earlier sections of this paper, we established the existence of both the necessary technology and the potential marketplace for mobile electronic commerce. We see a population of mobile phone and computing users who are (typically) young, technophilic and cash-rich/time-poor. Early examples of M-Commerce already under discussion include soft drink purchases from vending machines; and acceptance of directed advertising via mobile phone in return for discounted services (this attempts to take advantage of the ability to track the location of a mobile phone). It is clear, therefore, that commercial attention is already being drawn to seeking new services or new structures within existing markets which might allow mobile phone companies to redefine the mobile telephone business by offering services additional to voice communication or simple text messaging. In redefining the business of mobile telephony, the new facilities offered by IMT-2000 must be considered in conjuntion with the existing, and well-known characteristics of mobile telephony: •
6
Mobile phones are linked to individuals. Unlike a fixed landline, a mobile phone is used by its owner, rather than by a group of people, which implies that the originator of a call from a
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particular phone will have the same characteristics every time. Consequently, one could personalise the service provided to a subscriber simply on the basis of the telephone number – the user’s identification to an automated called party can be absolutely transparent, once the first contact between those parties has been established; •
Mobile phone service providers already have established credit checking, charging and billing systems, which are accepted by and familiar to their customers;
•
Mobile phone users accept that items charged to their account are, indeed, incurred by the user of the particular phone being used – that is, users routinely accept that charges on their phone bill were, indeed, made by the phone linked to the bill;
•
Mobile phone companies already, in effect, lend money to their subscribers. In essence, services are provided on credit and paid in arrears (although, of course, there are exceptions to this rule);
•
Security in electronic transactions has two major components – validation and nonrepudiation, both of which are relevant to service providers. Digital mobile phone networks are encrypted, ensuring that messages cannot be added, deleted or modified in transit, while the fact that the phone is uniquely identifiable prevents one of the major vendor-side problems with Internet-based E-Commerce – repudiation of transactions by consumers.
These characteristics offer the potential for mobile phone service providers to take a far greater role in the retail payments system than they have done to date. The most obvious potential application is as an alternative to credit cards for Internet-based services. A consumer, rather than providing his/her credit card number (with all the well-publicised risks that entails) could instead give their mobile phone number. The transaction could be validated by means of an automated call to that mobile phone, and the entry of an acceptance code – ensuring security for the purchaser and insurance against repudiation for the merchant. While it is quite possible for a mobile phone to be stolen, the only way in which it can be fraudulently used to initiate a transaction is for the thief to also obtain the PIN which operates the SIM card. By contrast, a credit card number is all that is required to initiate a transaction over the Internet. Of course, the use of a mobile phone to initiate ‚credit card-style‘ transactions is not restricted to the Internet. A mobile phone can also be used analogously to the way we currently use a credit card for face-to-face retail transactions. A transaction could be confirmed by automatic generation of a call to the purchaser’s mobile phone, asking for an acceptance code. Taking advantage of the applications which will be possible under IMT-2000, mobile phones will have the potential to supplement Internet-based electronic commerce for the nomadic computer user. Although it is clear that the limited keypads and screens available on today’s mobile devices limit the complexity of vendor systems which may be conveniently accessed (particularly from a moving vehicle), in principle the nomadic citizen might conduct (and pay for) any transaction using his/her mobile phone. One facility which brings this brave new world a little closer is the identification of mobile phones with specific users – and thus the ability to personalise the structure of the multi-part purchase transaction. We suggest that mobile phone service providers now have the chance to move into the retail payment system – taking up some (or all) of the space currently occupied by credit card companies. The credit card industry has been a milch cow for many years – and offers a significant opportunity for a new player to diversify, particularly one with an existing customer base. In particular, this opportunity favours the larger mobile phone companies, which are big enough to offer and manage the credit process.
5.
Conclusion
Mobile access – both in computing and telephony terms – is one of the major growth sectors of the next few years. The 1990s have seen both mobile telecommunications and electronic commerce mature and grow dramatically. The early years of the 21st century will see the fusion of these two sectors and the development of new and exciting applications for business and individuals. In this 7
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paper, we have provided an introduction to the recent technological advances in mobile telecommunications and nomadic computing – and suggested ways in which the fusion of these technologies could be realised commercially in the short-to-medium term. Mobile phone service providers are only just beginning to realise that they are not merely in the phone business. As the use of personal digital assistants becomes almost ubiquitous and as homes and offices become increasingly ‘intelligent’ and thus dependent upon connection with owners and users, the opportunities for nomadic computing and M-Commerce will grow and become pervasive. We have suggested one way in which mobile phone companies might take on the might of the credit card providers. Clearly, as more and more people use more and more ways of connecting with service and product providers in a variety of modes, there will a desperate need for a variety of interfaces which provide transparent access. Each device used should be appropriate for the time, place and purpose for which it is being used – although each device should offer a personalised window into the full range of services and products available.
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