Location-based services (LBS) are a general class of computer program-level services that use location data to control features. As such LBS is an information service and has a number of uses in social networking today as an entertainment service, which is accessible with mobile devices through the mobile network and which uses information on the geographical position of the mobile device. This has become more and more important with the expansion of the smartphone and tablet markets as well.
LBS include services to identify a location of a person or object, such as discovering the nearest banking cash machine (a.k.a. ATM) or the whereabouts of a friend or employee. LBS include parcel tracking and vehicle tracking services. LBS can include mobile commerce when taking the form of coupons or advertising directed at customers based on their current location. They include personalized weather services and even location-based games. They are an example of telecommunication convergence.
This concept of location based systems is not compliant with the standardized concept of real-time locating systems (RTLS) and related local services, as noted in ISO/IEC 19762-5 and ISO/IEC 24730-1. While networked computing devices generally do very well to inform consumers of days old data, the computing devices themselves can also be tracked, even in real-time. LBS privacy issues arise in that context, and are documented below.
Today the question about LBS (Location Based Services) is not, “what they are inside of,” but rather, “what they are not an active part of,” and the answer is, “very little”. They are a part of virtually all control and policy systems which work in computers today. They have evolved from simple synchronization based service models to authenticated and complex tools for implementing virtually any location based service model or facility.
LBS is the ability to open and close specific data objects based on the use of location and/or time as (controls and triggers) or as part of complex cryptographic key or hashing systems and the data they provide access to. Location based services today are a part of everything from control systems to smart weapons. They are actively used trillions of times a day and may be one of the most heavily used application-layer decision framework in computing today.
Research forerunners of today’s location-based services include the infrared Active Badge system  (1989–1993), the Ericsson-Europolitan GSM LBS trial by Jörgen Johansson (1995), and the master thesis written by Nokia employee Timo Rantalainen in 1995.
In 1990 International Teletrac Systems (later PacTel Teletrac), founded in Los Angeles CA, introduced the world’s first dynamic real-time stolen vehicle recovery services. As an adjacency to this they began developing location based services that could transmit information about location-based goods and services to custom-programmed alphanumericMotorola pagers. In 1996 Todd Glassey designed the first Digital Timestamp Server for Email and other content validation and created the first instances of “GeoSpatial Keying” a complex cryptographic process for using time and location data to access or ‘unlock’ certain key services. Glassey proceeded with his Digital Evidence System which was based on location and digital object control at the service and network layer interfaces. Later that same year (1996) the US Federal Communication Commission (FCC) issued rules requiring all US mobile operators to locate emergency callers. This rule was a compromise resulting from US mobile operators seeking the support of the emergency community in order to obtain the same protection from lawsuits relating to emergency calls as fixed-line operators already had.
In 1997 Christopher Kingdon, of Ericsson, handed in the Location Services (LCS) stage 1 description to the joint GSM group of the European Telecommunications Standards Institute (ETSI) and the American National Standards Institute (ANSI). As a result the LCS sub-working group was created under ANSI T1P1.5. This group went on to select positioning methods and standardize Location Services (LCS), later known as Location Based Services (LBS). Nodes defined include the Gateway Mobile Location Centre (GMLC), the Serving Mobile Location Centre (SMLC) and concepts such as Mobile Originating Location Request (MO-LR), Network Induced Location Request (NI-LR) and Mobile Terminating Location Request (MT-LR). These use models were not really functional at the application context layer and needed more user-interface controls to make them ubiquitous. Those control came from Glassey’s evolving models which expanded these and provided a secondary, more robust and very simple system for controlling digital objects and decision processes based on location and time.
As a result of these efforts in 1999 the first Digital Location Based Service Patent was filed in the US and ultimately issued after nine (9) office actions in March 2002. The patent has controls which when applied to today’s networking models provide key value in all systems.
In 2000, after approval from the worlds 12 largest telecom operators, Ericsson, Motorola and Nokia jointly formed and launched the Location Interoperability Forum Ltd (LIF). This forum first specified the Mobile Location Protocol (MLP), an interface between the telecom network and an LBS application running on a server in the Internet Domain. Then, much driven by the Vodafone group, LIF went on to specify the Location Enabling Server (LES), a “middleware“, which simplifies the integration of multiple LBS with an operators infrastructure. In 2004 LIF was merged with the Open Mobile Association (OMA). An LBS work group was formed within the OMA.
The first consumer LBS-capable mobile web device was the Palm VII, released in 1999. Two of the in-the-box applications made use of the ZIP code-level positioning information and share the title for first consumer LBS application: the Weather.com app from The Weather Channel, and the TrafficTouch app from Sony-Etak / Metro Traffic.
The first LBS services were launched during 2001 by TeliaSonera in Sweden (FriendFinder, yellow pages, houseposition, emergency call location etc.) and by EMT in Estonia (emergency call location, friend finder, TV game). TeliaSonera and EMT based their services on the Ericsson Mobile Positioning System (MPS).
Other early LBS include friendzone, launched by swisscom in Switzerland in May 2001, using the technology of valis ltd. The service included friend finder, LBS dating and LBS games. The same service was launched later by Vodafone Germany, Orange Portugal and Pelephone in Israel. Microsoft’s Wi-Fi-based indoor location system RADAR (2000), MIT’s Cricket project using ultrasound location (2000) and Intel’s Place Lab with wide-area location (2003).
In May 2002, go2 and AT&T Mobility launched the first (US) mobile LBS local search application that used Automatic Location Identification (ALI) technologies mandated by the FCC. go2 users were able to use AT&T’s ALI to determine their location and search near that location to obtain a list of requested locations (stores, restaurants, etc.) ranked by proximity to the ALI provide by the AT&T wireless network. The ALI determined location was also used as a starting point for turn-by-turn directions.
The main advantage is that mobile users do not have to manually specify ZIP codes or other location identifiers to use LBS, when they roam into a different location. GPS trackingis a major enabling ingredient, utilizing access to mobile web.
Control plane locating
Sometimes referred to as positioning, with control plane locating the service provider gets the location based on the radio signal delay of the closest cell-phone towers (for phones without GPS features) which can be quite slow as it uses the ‘voice control’ channel. In the UK, networks do not use trilateration; LBS services use a single base station, with a “radius” of inaccuracy, to determine a phone’s location. This technique was the basis of the E-911 mandate and is still used to locate cellphones as a safety measure. Newer phones and PDAs typically have an integrated A-GPS chip.
In order to provide a successful LBS technology the following factors must be met:
- Coordinates accuracy requirements that are determined by the relevant service;
- Lowest possible cost;
- Minimal impact on network and equipment.
Several categories of methods can be used to find the location of the subscriber. The simple and standard solution is GPS-based LBS. Sony Ericsson‘s “NearMe” is one such example. It is used to maintain knowledge of the exact location, however can be expensive for the end-user, as they would have to invest in a GPS-equipped handset. GPS is based on the concept of trilateration, a basic geometric principle that allows finding one location if one knows its distance from other, already known locations.
GSM localization is the second option. Finding the location of a mobile device in relation to its cell site is another way to find out the location of an object or a person. It relies on various means of multilateration of the signal from cell sites serving a mobile phone. The geographical position of the device is found out through various techniques like time difference of arrival (TDOA) or Enhanced Observed Time Difference (E-OTD).
A low cost alternative to using location technology to track the player, is to not track at all. This has been referred to as “self-reported positioning”. It was used in the mixed reality game called Uncle Roy All Around You in 2003 and considered for use in the Augmented reality games in 2006. Instead of tracking technologies, players were given a map which they could pan around and subsequently mark their location upon. With the rise of location-based networking, this is more commonly known as a user “check-in“.
Another example is Near LBS (NLBS), in which local-range technologies such as Bluetooth, WLAN, infrared and/or RFID/Near Field Communication technologies are used to match devices to nearby services. This application allows a person to access information based on their surroundings; especially suitable for using inside closed premises, restricted/ regional areas.
Another alternative is an operator- and GPS-independent location service based on access into the deep level telecoms network (SS7). This solution enables accurate and quick determination of geographical coordinates of mobile phone numbers by providing operator-independent location data and works also for handsets that are not GPS-enabled.
Many other Local Positioning Systems are available, especially for indoor use. GPS and GSM do not work very well indoors, so other techniques are used, including Co-Pilot Beacon for CDMA Networks, Bluetooth, UWB, RFID and Wi-Fi. But which technique provides the best solution for a specific LBS problem? A general model for this problem has been constructed at the Radboud University of Nijmegen.
Location Based Marketing Best Practices
- LBS applicationsAddress consumer confusion. Most consumers will have a natural tendency to shy away from Location Based Services.
- Provide clear opt-in instructions. Explain as quickly and clearly as possible to your prospects and customers how to opt in to your location-based marketing program.
- Explain to consumers what they can expect after they’ve opted in to your program. That way, you’ll avoid unpleasant surprises for your target audience.
- Test the campaign on unbiased candidates.
- Make it worth their while. You’re asking customers to opt in to your location-based marketing program, so reward them for their trouble.
Some examples of location-based services are:
- Recommending social events in a city
- Requesting the nearest business or service, such as an ATM, restaurant or a retail store
- Turn by turn navigation to any address
- Assistive Healthcare Systems
- Locating people on a map displayed on the mobile phone
- Receiving alerts, such as notification of a sale on gas or warning of a traffic jam
- Location-based mobile advertising
- Asset recovery combined with active RF to find, for example, stolen assets in containers where GPS would not work
- contextualizing learning and research
- Games where your location is part of the game play, for example your movements during your day make your avatar move in the game or your position unlocks content.
- Real-time Q&A revolving around restaurants, services, and other venues
More examples are listed in.
For the carrier, location-based services provide added value by enabling services such as:
- Resource tracking with dynamic distribution. Taxis, service people, rental equipment, doctors, fleet scheduling.
- Resource tracking. Objects without privacy controls, using passive sensors or RF tags, such as packages and train boxcars.
- Finding someone or something. Person by skill (doctor), business directory, navigation, weather, traffic, room schedules, stolen phone, emergency calls.
- Proximity-based notification (push or pull). Targeted advertising, buddy list, common profile matching (dating).
- Proximity-based actuation (push or pull). Payment based upon proximity (EZ pass, toll watch), automatic airport check-in.
In the U.S. the FCC requires that all carriers meet certain criteria for supporting location-based services (FCC 94–102). The mandate requires 95% of handsets to resolve within 300 meters for network-based tracking (e.g. triangulation) and 150 meters for handset-based tracking (e.g. GPS). This can be especially useful when dialing an emergency telephone number – such as enhanced 9-1-1 in North America, or 112 in Europe – so that the operator can dispatch emergency services such as Emergency Medical Services,police or firefighters to the correct location. CDMA and iDEN operators have chosen to use GPS location technology for locating emergency callers. This led to rapidly increasing penetration of GPS in iDEN and CDMA handsets in North America and other parts of the world where CDMA is widely deployed. Even though no such rules are yet in place in Japan or in Europe the number of GPS-enabled GSM/WCDMA handset models is growing fast. According to the independent wireless analyst firm Berg Insight the attach rate for GPS is growing rapidly in GSM/WCDMA handsets, from less than 8% in 2008 to 15% in 2009.
As for economic impact, location based services are estimated to have a $1.6 Trillion impact on the US economy alone.
European operators are mainly using Cell-ID for locating subscribers. This is also a method used in Europe by companies that are using cell based LBS as part of systems to recover stolen assets. In the US companies such as Rave Wireless in New York are using GPS and triangulation to enable college students to notify campus police when they are in trouble. Rave Wireless and other companies with location based offerings are powered by a variety of companies, including Skyhook Wireless, AlterGeo and Xtify.
Comparison of location tracking apps for mobile devices
Currently there are roughly three different models for location-based apps on mobile devices. All share that they allow one’s location to be tracked by others. Each functions in the same way at a high level, but with differing functions and features. Below is a comparison of an example application from each of the three models.
|Function||Google Latitude||Find My Friends||Nearby||Pathshare – Realtime Location Sharing|
|Operating systems supported||iOS, Android, BlackBerry OS, Windows Mobile, Symbian S60||iOS only||Windows Phone, Windows Mobile, Windows 8, iOS, Facebook||iOS, Android|
|Web application available||Yes||No||Yes||Yes|
|User identification||Google Account||Apple ID||no account needed|
|Update frequency of location||Dynamically periodic||On demand by remote user||On demand by remote user||dynamically periodic|
|Stale location behaviour||Last reported location||Unknown location||Last reported location||last reported location|
|Location history||Optional, visible only to tracked user||No||No||No|
|Temporary location sharing||No||Yes, multiple users with expiry date & time||No, always shared||Yes, user sets time limit|
|Bilateral sharing of location with friends||Yes by default||No by default||Yes, mandatory||Yes (invisible mode available)|
|Precision levels configurable on a per-friend basis||Best location, city-level or hidden||Best location only||Best location only||Best location only|
|Manually configure location||Yes||Yes||Yes||No|
|Check into nearby place||Yes||No||No||No|
|Custom location labels||No||Yes||No||No|
|Source of friends’ names and photos||Friends’ Google profiles||User’s own contacts from local iOS device||Nearby Profile||User’s own contacts from device|
|Maximum distance calculated to friends’ locations||5000 miles||99 km or 99 miles||Infinite||Infinite|
Mobile messaging plays an essential role in LBS. Messaging, especially SMS, has been used in combination with various LBS applications, such as location-based mobile advertising. SMS is still the main technology carrying mobile advertising / marketing campaigns to mobile phones. A classic example of LBS applications using SMS is the delivery of mobile coupons or discounts to mobile subscribers who are near to advertising restaurants, cafes, movie theatres. The Singaporean mobile operator MobileOne carried out such an initiative in 2007 that involved many local marketers, what was reported to be a huge success in terms of subscriber acceptance.
Companies offering location-based messaging (sometimes referred to as “geo-messaging”) include The Coupons App (US), Central (International), Zhiing (international), BluePont (US), Loopt (US), Dodgeball (US) and Beamster (Austria).
The Location Privacy Protection Act of 2012 (S.1233) was introduced by Senator Al Franken (D-MN) in order to regulate the transmission and sharing of user location data in USA. It is based on the individual’s one time consent to participate in these services (Opt In). The bill specifies the collecting entities, the collectable data and its usage. The bill does not specify, however, the period of time that the data collecting entity can hold on to the user data (a limit of 24 hours seems appropriate since most of the services use the data for immediate searches, communications, etc.), and the bill does not include location data stored locally on the device (the user should be able to delete the contents of the location data document periodically just as he would delete a log document). The bill which was approved last month by the Senate Judiciary Committee, would also require mobile services to disclose the names of the advertising networks or other third parties with which they share consumers’ locations.
With the passing of the Can Spam Act in 2005, it became illegal in the United States to send any message to the end user without the end user specifically opting-in. This put an additional challenge on LBS applications as far as “carrier-centric” services were concerned. As a result, there has been a focus on user-centric location-based services and applications which give the user control of the experience, typically by opting in first via a website or mobile interface (such as SMS, mobile Web, and Java/BREW applications).
The European Union also provides a legal framework for data protection that may be applied for location-based services, and more particularly several European directives such as: (1) Personal data: Directive 95/46/EC); (2) Personal data in electronic communications: Directive 2002/58/EC; (3) Data Retention: Directive 2006/24/EC. However the applicability of legal provisions to varying forms of LBS and of processing location data is unclear.
One implication of this technology is that data about a subscriber’s location and historical movements is owned and controlled by the network operators, including mobile carriers and mobile content providers. Mobile content providers and app developers are a concern. Indeed, a recent MIT study by de Montjoye et al. showed that 4 spatio-temporal points, approximate places and times, are enough to uniquely identify 95% of 1.5M people in a mobility database. The study further shows that these constraints hold even when the resolution of the dataset is low. Therefore, even coarse or blurred datasets provide little anonymity. A critical article by Dobson and Fisher discusses the possibilities for misuse of location information.
Beside the legal framework there exist several technical approaches to protect privacy using privacy-enhancing technologies (PETs). Such PETs range from simplistic on/off switches to sophisticated PETs using anonymization techniques, e.g., related to k-anonymity. Only few LBS offer such PETs, e.g., Google Latitude offered an on/off switch and allows to stick one’s position to a free definable location. Additionally, it is an open question how users perceive and trust in different PETs. The only study that addresses user perception of state of the art PETs is. Another set of techniques included in the PETs are the Location obfuscation techniques, which slightly alter the location of the users in order to hide their real location while still bein able to represent their position and receive services from their LBS provider.