A SERVICE ORIENTED APPROACH TO MOBILE GEOLOCATION P.C. Kikiras1 & D. Drakoulis2 (1)Department of Electrical & Computer Engineering , Division of Communication, Electronic and Information Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15773 Athens, Greece E-mail:
[email protected] (2) R&D Manager, R&D Department, EXODUS, Filolaou 40, Athens 11633, phone + 30 210 7564505, fax + 30 210 7563096 E-mail:
[email protected]
Abstract Following a long period of doubts over their long-awaited success, location services have recently dynamically emerged to transform the way users experience content related services. The following contribution attempts to evaluate the shift from an operators’ driven market to a fully evolved open area of opportunities for content providers and application developers alike. In the paper, this shift shall be explained on the transformation of the business model and further supported by the implementation of standard-based service provisioning architectures, which augment the functionality and content experienced by the end user. Introduction The decade-lasting evolution of location services for mobile networks, is a story of high expectations, serious doubts and then great disappointment, depending on the person or the time this story is written. Nevertheless no one doubts it is a fascinating story, with what seems to be now a bright future ahead. In the next sections we will present the pre-standard era of location service deployments, examining technical as well as non-technical inefficiencies. Following we identify the important influence of Service Oriented Architecture on current and future service deployments. We proceed by outlining the emergence of a fully expanded services delivery chain and conclude by presenting a representative case of a mobile service portal (i-mode™) which emerged from a Japanese success story to a worldwide model for the mobile services industry. Initial location and geospatial service offerings In the absence of well defined architectures and primarily the lack of standardized interfaces, the initial Location Based Service offerings (largely the ones introduced in Europe before and during 2001) were based on the use of non-standard mechanisms for the extraction of the mobile user’s location in the network. All major manufacturers struggled to establish their version of a specialized node in the network infrastructure either entitled as GMLC or MPC (by European or US operators) which would fuse the position estimate with an application imported from outside the network. Faint initiatives from manufacturers as in the case of Ericsson’s MPP lagged
behind the market needs [1] and before 2001 only proprietary interfaces based on XML or CORBA are appearing [2].
Figure 1 - Early LBS Architectures
Situation was similar with respect to the geospatial functionality, as web-enabled GIS transactions were only then evolving and no single dominant product existed which might be used by the majority of the application developers. Requirements for GIS mapping services were handled by proprietary XML implementations. It was the responsibility of the application provider to acquire suitable GIS data from a third vendor or to own the GIS infrastructure and consequently correlate the imported location information with its own GIS data to return the results to the operator to be served back to client (referring to figure 1). Consequently developers would use different GIS, each with its own developed API. The absence of standards during the period, forced the mobile operators, being the only actors in what was considered a mobile service chain, to be reluctant in adopting location based services offered by application developers. Severe integration problems with their existing systems, lack of service uniformity, poor interoperability were the technical factors plaguing their initial location service offerings. Given the legislative uncertainties, the potential for exposing location to service providers was from the very beginning ruled out by operators mainly in the excuse of handling privacy issues, in essence depriving users of other services, as well as excluding service providers from the service value chain. Service chain restrictions Haunted by such technical inefficiencies, mobile service delivery models additionally suffer severely from the issues revolving around the non-uniform business model of the operators. The location service process itself was ill-defined: the lack of a concrete user-centric transactions workflow as well as a scheme that would enable revenue sharing between mobile operators and the other actors, severely harmed even the most advanced technical solutions. In what is thought to be as the single most important positive effect of the recent market crisis, the operators gradually embrace the view that the specific nature of such service offerings requires the cooperation of other actors, whose role was previously known only as theory in the mobile value chain (one example is the emergence in some markets of the location middleware vendors which may also offer
ASP-type of service – see the example of Webraska [3]), as well as the uniform offering of such services as part of a “portal” easily accessed, well safeguarded, still open to 3rd parties. The need for clear - and to some extent standard-based charging policies which would emphasize on revenue sharing with 3rd parties became apparent. In the recent past, simple, clear charging models proved favorable [4]. This is for example the case of the service mobile portals where •
subscription-based flat monthly rates are charged for services
•
clear transaction-based charging is used for content
while the operator essentially seeks to attract traffic usage based on the abundance of network throughput as 3rd generation networks are being launched and established. The influence of the SOA model on technology In what seems now as the perfect timing, while the mobile service industry was in the process of defining the standards that would rule the coordination of functionality as well as the exchange of location information among different actors, a novel approach to using distributed computing resources was rapidly advancing as an alternative to the traditional component - based paradigm. The proposed novel architecture is being founded on the principles of Service Oriented Architecture - SOA. SOA describes a distributed computing environment where software resources are made available as services over the network and not as programming constructs [5]. The interaction between the applications which provides a service and the application which consumes the service is based on conversational, message-based interactions, conformant to a particular protocol and data description. In that context SOA offers descriptions of what messages are suitable input and output, to and from the service, and under what conditions they are exchanged, without dealing with the specific implementation matters. In its most general usage, a SOA allows parties to discover useful and compatible services [5]. The implementation of SOA proposed by both academia and industry were the programmatic interfaces referred to as “Web Services”, whose fundamental concept was simply to allow Remote Procedure Calls (RPCs) against an object over the internet or any type of network. Web Services use platform – neutral standards such as SOAP /HTTP and XML. Exchange of location between application providers and network operators is implemented according to well predefined open and cross-industry adopted standards such as LIF/MLP and OpenLS, though specific vendors implementations (two common examples being ESRI’s ArcWeb Services, Microsoft’s MapPoint.NET Web Services) have not ceased to exist. In the emerging architecture the new location related actors are well established: Location Service and (geospatial) Content Providers (SP and CP respectively). One specific implementation of the web services, defined under OGC’s OpenLS initiative [6], facilitates the use of location and other forms of spatial data in the wireless environment, as well as the integration of spatial data and processing resources into telecommunications and Internet services infrastructure [7], [8].
MPC/GMLC
LIF / MLP
Network controller
Location Service Provider
LIF - OpenLS GeoServ er
Radio tower
LIF - OpenLS
Mobile Operator
Data GEO
Spati al
Geospatial Content Provider
Serv e r Serv e r
Serv e r
Application Provider
Figure 2 - Concurrent standard-based LBS Architecture
With the adoption of the LIF/MLP and OpenLS standards, technical considerations on exchange of LBS content and distributed application logic are to a large extent resolved. However the type and method of information exchanged between actors, raises indeed privacy, data integrity and generic security considerations. The communication of the users’ identities and vital location data, requires a protected link with the MOs database ensuring all aspects such as authentication of the requesting party, security in the communication part. Whereas authentication of localized users by the network is implemented on the basis of user identity as well as equipment used, minimization of fraud by service providers is achieved either by using SQL queries on database information or structured approaches such as LDAP searches. The evolving location service “ecosystem” In the following architecture, the previously straightforward interaction between mobile operators and application providers introduced in figure 1, has been enhanced by the introduction of multiple actors actively involved in the service delivery process, including the mobile service portal owner (who, contrary to common belief, may be distinct from the mobile operator), the location service provider, the location content provider as well as third parties involved directly or indirectly in diverse location service bundles.
Functionality Voice, Data Provisioning
- Subscription Fees - Direct Service Fees for Voice Traffic and GPRS data
WML / iHTML Data
End User
Functionality for End User: One-Stop-Shop for End-User Services
Mobile Operator
for Content Providers: - Billing - Content Aggregation
Portal
WML / iHTML Data
iMode VF Live!
Fees per Data Location Service Provider: LIF MLP used for position (x,y,accuracy) Positioning Fees Revenue Sharing
Mobile Operator: Address, Routing Indications used for Voice Services
3rd Content Providers Unofficial Sites
Positioning Fees
Address, Routing Indications
Location Service Providers Webraska (US) Microsoft MapPoint
Maps and Location Information
Positioning Fees
Address, Routing Indications
HTML content, ASP searches
Authorized Content Providers (Leisure Magazines)
Periodic data supply contracts ?
Location Content Providers
Functionality Geocoding, Reverse Geocoding, Proximity Searches, Routing
Figure 3 - The evolving mobile location services "ecosystem"
Location Service Providers (LSP) act as brokers between network operators and application providers. Their main task is to gather location information in the form of x,y coordinates from the mobile operators’ MPC/GMLC then transform the information as address data, routing instructions, proximity searches for consumption by users, application providers or even by the operator to be used by intelligent IVR (Interactive Voice Response) services as audible information. Operations concerning privacy, presence and personalization are also handled by LSPs. Location content providers (LCP) role is to provide maps and Points-of-Interest information to LSPs. The respective information exchange is governed by an open interoperable standard which considers and respects privacy and security. Periodic (subscription based) data supply contracts are signed with the LSPs. However the critical emerging role is the mobile service portal (MSP), which comes to serve the requirement for offering one-stop-shopping mobile services (including location services) based on a novel uniform, transparent and simplified business model. In the next we will explain the MSPs’ decisive role in creating a “killerenvironment” which adds value to the mobile network. Emergence of mobile service portals – the case of i-mode An MSP success story is definitely “i-mode” marketed by NTT DoCoMo of Japan, which has exceeded its national identity and following Japan is advancing across Europe. The “subscription-based automatic renewal” model proposed thereby, is well defined, clearly dimensioned and religiously obeyed by any interested party.
Obviously not only the operator gains significantly from applying the i-mode model for the increased use of network resources it ensures, but also the service provider gets to share revenue from monthly fees collected by the MSP [9].
Figure 4 - The "Subscription-based automatic renewal" business model of i-mode
With regard to revenue scheme, only minimal subscription rates may be charged (less than €3/month/site, with pricing that comes at €0.25 increments) and the user clearly knows when he is charged and what he is charged for. Restrictions apply to the overall volume downloaded to the subscriber as each page may not exceed 10kB. User may not be tricked into visiting external sites where no restrictions would apply, as inserting links is forbidden! Generally a 9% commission for the operator to the revenue of official (authorized) sites applies. Part of i-mode success is to be credited to the wealth of free information ensured based on both the “semi-walled garden” used by i-mode, as well as the use of free content areas – a feature highly recommended by DoCoMo. Indeed besides the 3000 sites already registered with i-mode (a small fraction of which in Europe), user may globally access a total of more than 50000 3rd party sites compatible with the i-mode browser. An alternative idea applicable to location-related content or services is the provision of full content for small amount of transactions, using credit counters (while the first route on a map is provided for free, next ones are charged). It is highly important that momentarily no advertisement is allowed as this would lead to subscribers been charged for downloading undesirable data. Personalization of services is supported at the moment, in the absence of a standard profiling mechanism, by means of access to an associated HTTP site, where following the initial registration with the authorized Service Provider the user may regularly review his subscription status as well as configure the service according to his needs via access to the SP’s web site. Concluding, while i-mode clearly does not build on its technical advance, it definitely introduces a clear framework which both ends of the value chain (the end-user as well as the SP / CP) will demonstrably trust. Loyalty, built on trust, is a motive for the SP / CP, especially given that following the service launch, minimal advertising costs are required. The business model works as the ARPU for networks that already operate the i-mode portal is €8-10.
Conclusion – The way ahead In this contribution we reviewed the use of the SOA model for the engineering of high value services, which makes use of distributed resources and showed how this innovative methodology will eventually transform the way we view location services today. A small number issues raised are nevertheless still left unanswered; the level of abstraction in accessing network facilities, the issues relative to service charging, accounting for the introduced services and indeed users’ data handling. Resolving these issues is not solely a technical objective; it is actually the means towards promoting the users’ understanding of how their vital data are manipulated and achieving awareness of the benefits introduced by such service offerings. While ETSI 3GPP and 3GPP2 pioneered the progress made on the overall incorporation of location services in the network architecture, the service and content providers alike will look at OMA as the de-facto standardization body to research and adopt content interfaces, driven however by the stronger voices of manufacturers and operators. Nevertheless OMA (Location SubWG) is the exclusive policy maker for such issues as privacy, security, charging and roaming. The subscriber’s privacy, security and safety are dealt with at EICTA, EC, as well as CTIA, FCC and UMTS Forum at a global level.
References [1] Mobile Positioning Protocol, Ericsson, www.ericsson.com [2] XWLI from SignalSoft, www.signalsoft.com [3] Webraska site, www.webraska.com [4] M. Basso, “Don't Get Lost in the Mobile Location Service Ecosystem”, Research Note, Gartner Group, July 2002. [5] OMA Web Services Enabler (OWSER): Overview (Draft Version 1.0 -16 Feb 2004) [6] Open GIS Consortium 2002, OpenLS Initiative: Building a Foundation for Location Services [7] J. Spiney, 2003, A brief history of LBS and how OpenLS fits into the new value chain, ESRI Whitepaper. [8] Location Based Services Interoperability Issues, presentation by Bosco Eduardo Fernandes, chairman, Chair ICTG (IT-Media) and Manufacturers Sector Group UMTS Forum, 3G Services EC Workshop, Brussels 2004 [9] “i-mode: From bandwidth problem into Internet phenomenon”, article by Veronika Megler, IBM Solutions Integration Technology Center, IBM Developer Works, February 2002. [10] EXODUS development for planned i-mode deployments.
