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Implementations of location awareness technologies and their applications

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Location awareness technologies open the doors to developing exciting new applications. With the availability of commercial products built on this technology, it is possible to put this technology in everyday use. The most common implementations currently in use are navigation systems installed in most modern vehicles. These applications make use of global positioning system (GPS). This paper explores two location aware implementations namely Intel's Place Lab and Microsoft's mappoint location server which became available and are built around an alternate method of location determination. These cost effective and easy to integrate implementations can be leveraged for many useful applications to provide value added services ranging from living a more productive lifestyle to efficient response during emergency situations.
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Khaled Elleithy & Arif Maqbool
Department of Computer Science
University of Bridgeport
Bridgeport, CT 06604
Abstract -
Location awareness technologies open the doors to
developing exciting new applications. With the availability of
commercial products built on this technology, it is possible to
put this technology in everyday use. The most common
implementations currently in use are navigation systems
installed in most modern vehicles. These applications make use
of Global Positioning System (GPS). This paper explores two
location aware implementations namely Intel's Place Lab and
Microsoft's MapPoint Location Server which became available
and are built around an alternate method of location
determination. These cost effective and easy to integrate
implementations can be leveraged for many useful applications
to provide value added services ranging from living a more
productive lifestyle to efficient response during emergency
situations.
I. INTRODUCTION
Internet is a vital part of our everyday lives and is the
primary source for finding information. The ability to find
what we need without making a trip to each location helps us
save valuable time and resources. Advances in mobile and
wireless communications have extended the scope of
computer applications and have opened the doors to new
types of value added services such as applications providing
real-time driving directions while we are on the move.
These applications rely on Global Positioning System (GPS)
which uses satellites to determine the current location in
terms of longitude and latitude co-ordinates. This
information can then be used to determine a position on the
map. GPS primarily works outdoors with a positioning
device that can transmit and receive positioning information
through a line of sight (LOS) to the roaming satellites
around the earth.
Recent developments in location awareness
technologies make use of existing communication
infrastructure such as 802.11 (Wi-Fi) access points [1]. This
paper explores two of these alternate location determination
technology based software implementations from Intel and
Microsoft namely Intel's Place Lab and Microsoft's
MapPoint Location Server.
The main advantage provided by both of these
implementations is that they leverage existing
communication infrastructure around us thus providing a
cost effective solution to develop location aware
applications. Some applicable scenarios are also discussed
which can be deployed by enterprises to gain operational
efficiency as well as provide value added services to their
customers.
II. IMPLEMENTATION
A. Intel’s Place Lab
Place Lab software was developed by Intel Corporation
which promises to provide low cost and easy to use device
positioning for location awareness applications. Place Lab
relies on communication infrastructure such as 802.11
access points, GSM towers and fixed Bluetooth devices.
Radio beacons from these devices can be uniquely identified
through their MAC address which in turn can be looked up
in a location database to identify the location of the mobile
communication device [2].
Place Lab clients are developed using Place Lab
libraries available in Java 2 Micro Edition (J2ME). The
Place Lab clients use live radio observations and cached
beacon locations to form an estimate of their location. The
client functionality is broken into three logical pieces:
spotters, mappers and trackers [3]. Spotters are used to
observe the physical surroundings of the client and capture
the IDs of the observed radio beacons. For the various
protocols supported by Place Lab, a spotter is available that
can monitor the signals on that protocol. For example, in a
client, there may be a spotter for Bluetooth and another
spotter for 802.11. The information obtained by the spotters
is passed on the mappers.
The task of the mapper is to provide the location of
known beacons. The location includes a latitude and
longitude in addition to other useful information like the
antenna altitude, the age of the data, a learned propagation
model, or the power of the transmitter. The mapper
component can retrieve the location information from a
database or previously cached location information. The
third part of the client is called the tracker. Tracker uses the
streams of spotter observations and associated mapper data
to produce estimates of the user's position. The trackers
encapsulate the system's understanding of how various types
of radio signals propagate and how propagation relates to
distance, the physical environment and location. The
advantage of using Place Lab is its low cost implementation
of location awareness. Existing mobile devices can be used
Implementations of Location Awareness
Technologies and their Applications
1-4244-0697-8/07/.00 ©2007 IEEE.
in conjunction with the centralized database of locations
which is provided by Place Lab.
Fig. 1: Architecture of Place Lab [3]
This database, however, is still not comprehensive and
significant information must be available in the user's
locality for the intended implementation to be meaningful.
Place Lab also provides an application called Stumbler
which can be downloaded on the client and runs in
conjunction with a GPS device. This application gathers
information of the surrounding infrastructure of Wi-Fi
access points, GSM towers and Bluetooth devices. Using
this application, the location information can be quickly
populated which can then be made available to the
centralized database. In this way, a locality which lacks
entries in the database can be quickly and easily populated
with the available location information of the surrounding
communication infrastructure used by Place Lab.
The accuracy of Place Lab's location estimation ranges
from about 20 meters in urban areas to about 40 meters in
suburban neighborhoods [4]. The accuracy of Place Lab
relies on the number of radio beacons it receives in a given
time frame.
Place Lab provides a software development kit (SDK)
written in Java language that can be easily integrated with
applications to make use of location awareness.
B. Microsoft Map Point Location Server
MapPoint Location Server allows users to connect real-
time location information from mobile operators with
mapping and routing information from the MapPoint Web
Service so that real-time location can become an integral
part of business applications [5].
The architecture of MapPoint Location Server is
captured in Fig. 2. MapPoint gets real time location
information of a user through the cellular towers the user is
close to. Alternatively, the client co-ordinates could also be
determined through a GPS device. The main interface to
MapPoint Location Server is its web service which allows
for easy integration with existing and new applications that
require the use of the location information. Once user's co-
ordinates are sent to the Map Point Web Service, the
location can be displayed on the map.
Fig. 2: MS Location Server Architecture
MapPoint also allows for uploading custom location
information (such as the locations of all Safeway stores in a
city) which is then made available through the MapPoint
Web Service.
Companies who wish to include their own location
information can do so and in turn provide the location
information through their applications. As an example, we
show a program's output which makes use of Location
Server to determine the nearest places on the Map where
Fourth Coffee (a fictitious company) has its stores [5].
In this scenario, a user who wishes to find out the
nearest location of this company's store would make the
request on hi/her mobile device. The user's location
information would be sent back to the business application
which will make use of the MapPoint Web Service and send
back the results to the user in the form of a map highlighting
the current location of the user and the directions to the
destination. Fig. 3 demonstrates the output of this program
on a Pocket PC simulator.
Uploading location information is also very easy and
multiple formats are supported. A simple comma delimited
file with address information and latitude and longitude
information is sufficient to upload the locations of interest
for a particular implementation such as the one discussed in
the previous section.
MapPoint relies on cellular service provider specific
plug-ins which can be installed on the mobile devices to
transmit location information of the user.
III. APPLICATIONS OF LOCATION AWARENESS
The applications presented in this section can be built
upon the two implementations discussed in the previous
section to provide the following advantages.
1. Provide a cost effective implementation without the
need for additional hardware such as that required
by GPS based systems.
Fig. 3: Showing nearest point of interest
2. Provide location awareness indoors or places where
GPS can not be used (where line of sight is not
available to satellites).
3. The flexibility to define your own locations to create
a fully customized location map.
As an example, a person who makes an emergency call
inside a building using a specialized application that can also
transmit location co-ordinates could potentially save lives
especially if the person falls unconscious. Similarly, in
other scenarios such as tourism in remote terrains such as
mountains and caves, a GPS based system may not be able
to provide complete coverage. The following sections take a
closer look at these possibilities.
A. Fleet Management
Companies operating fleet of vehicles such as logistics
companies require knowledge of the location of their mobile
assets at any given point in time. Real-time fleet
management has a tremendous value and benefits include
improved customer service, increased productivity through
better scheduling, as well as enhanced driver safety and asset
protection. Fleet management is also used to provide better-
estimated arrival times, improve on-time delivery by
rerouting vehicles, monitor and optimize vehicle customer
stops, check for on-route compliance, conduct post-route
analysis to improve scheduling, safeguard drivers and
protect vehicle assets, track driver safety by monitoring
vehicle speed and travel patterns and monitor vehicle use
during and after work hours. Additionally, it may be
required to determine an asset position in real-time. With
location awareness capabilities, each asset's current location
is always known.
Both Place Lab and MapPoint Location Server can
provide a low cost implementation for developing a fleet
management solution. In either of the two implementations,
existing assets such as cellular phones or wireless enabled
devices can be put to use to provide location information to
the fleet hub.
Besides logistics companies, another application of fleet
management is cab companies. When a person requiring a
cab calls upon the cab company, through its real time
location information of all the vehicles, the cab company can
dispatch the nearest available cab to where the person is
waiting for the cab. In this situation, since both the location
of the customer and the cab are known, the information can
be carried over to the navigation system fitted inside the cab
so that the cab driver can follow the directions to pickup the
waiting party. Such an implementation will increase the
operational efficiency of the cab company.
Another useful example can be in emergencies where
someone requiring immediate assistance would make a
phone call using a cellular phone to emergency operators. In
such a situation, the location of the person requiring
assistance can be determined through his/her cellular phone
signal. Combining this information with the fleet
management solution comprising of mobile emergency
response teams, an efficient response can be initiated which
could save vital time that can be extremely valuable in life
threatening situations. In such a situation, both the location
of the requester and emergency team are known and hence
driving directions can also be provided to the mobile
response team.
While being a low cost solution, the fleet management
is somewhat restricted as it relies on the availability of
cellular towers and Wi-Fi access points and absence of these
can result in loss of coverage. The fleet management
through this strategy is therefore ideal for city wide or state
wide coverage. For global coverage, it may be desirable to
use the satellite positioning option in tandem with the
cellular and wireless positioning [6].
B. Tourism
In today's world, making a trip to popular tourist
attractions such as Grand Canyon or Yellow Stone National
Park requires extensive planning. Once on the tourist
location, visitors have to often hire guides and rely on paper
based maps to explore the area. In small locations, this is
generally not a major problem but when the tourist location
spans a vast area, this can be somewhat challenging. It can
also be difficult to find guided tours during peak season.
Bringing location awareness to tourism can allow tourist
attractions to be available on electronic maps. Virtual tourist
application can guide the visitors through the attraction in
much more detail including navigating through the attraction
and highlighting important points of interest.
For extreme sports such as high altitude mountain
climbing, rescue workers can have significant problems in
locating people in need of assistance due to the harsh
environmental conditions. Location awareness capability
can assist in rescue workers to be aware of the location of all
adventurers in the area as well as quickly reach the
distressed party in need of assistance.
The main challenge with deploying location aware
application based on the technologies discussed earlier in
this paper is that the tourist spots tend to be in remote
locations where Wi-Fi and cellular towers may not be
installed due to environmental challenges and constraints. In
such remote places where this facility is not available, it may
be necessary to setup a local wireless network with various
access points that can serve the area and provide the
alternate for the existing infrastructure in place in other
urban areas. This may increase the operational cost but the
benefits can be significant which can range from providing
more personalized service to the visitors as well as
accurately locating people requiring assistance in
emergencies.
The major challenge in the tourism scenario is lack of
positioning information [7]. Significant efforts are required
to address this gap before such an application can be made
available across all major tourist attractions.
C. Electronic Queuing
A person requiring a specific type of service such as
renewing his/her driver's license at the DMV office may
have to wait in long queues before their turn comes up.
Mobile queuing can allow users to electronically queue in
without having to be physically present at the location. The
queuing application can inform the user of the wait time and
the expected time at which they should be physically present
at the location to receive service. As the queue moves, the
application can update the user in real time of their number
in the queue. The time which would normally be spent idly
waiting in long queues can be productively used elsewhere.
Mobile Queuing can have a significant advantage at
theme parks [8]. Theme parks often have long wait lines
and require people to physically wait in these queues before
they can enjoy the ride. This wastes a lot of time as the
visitors could use this time to enjoy other rides which have a
lesser waiting time. Combining location aware technologies
with electronic queuing, a person visiting the theme park can
enjoy a much richer experience as they can electronically
queue in for each ride which can constantly update them of
their ride time as well as provide them an electronic map of
the entire theme park which they can navigate to get from
ride to ride. This will allow the visitors to plan their day
better by being aware of all the rides along with their
corresponding wait times.
D. Nearest Location of Interest
The main objective in providing personalized services is
to be able to determine where a person is and deliver content
and services in a context that brings true value and
improvement to their quality of life. Information such as the
nearest gas station, ATM, restaurant, hotel etc can have great
value for users. Such an application can be provided by cell
phone service providers as a value added service for users
who wish to subscribe to such services. As mobile service
providers strive to achieve market differentiation, increase
revenue and gain new customers, location based services can
help operators stand out in the market and strongly
differentiate from their competition.
Such an application has other potential as well for
ordinary businesses. Companies like major grocery store
chains and gas stations can provide their outlet locations
through services managed by them. In this situation, a user
would use his/her cellular phone that can transmit its
location to the specific company's location service, such as a
grocery store. The location service would in turn provide
the information of all the nearest outlets to the requesting
customer. Additionally, the user can be provided with
driving directions on how to reach their chosen location
from the results. Companies that take an early initiative in
becoming location aware can also hope to have a larger
customer loyalty through these value added services.
As more and more companies take the initiative to
provide location information of their service outlets, be it
grocery store locations or ATM's of a particular bank, the
information can be collected and compiled into a large
virtual directory of service provider locations [9]. This
presents another opportunity for companies, such as those
providing current applications for navigation systems in
automobiles, to provide navigation systems equipped with
the capability to search for a specific location of interest and
be able to provide directions to the nearest such location.
IV. FUTURE WORK
Context awareness applications provide significant
challenges from implementation perspective. Intel and
Microsoft are coming out as the leaders in providing a
platform for developing location aware applications. As the
development and adoption of location based services grows,
there will be a need to consolidate the service offerings from
different service providers. Although this paper does not go
into the details of providing such a service base, the need for
a consolidated service delivery mechanism [10] can not be
overlooked. In addition to this, the issue of privacy and
security also needs to be investigated in further detail.
Privacy and security tend to be the major issues in the
roadmap towards general adoption of location aware
applications. The major topics identified for further research
include:
Architecting a common framework for seamless
integration and delivery of location based services
Protecting user privacy in terms of user’s location
information being exposed without consent
Security of information being transmitted between the
service provider and the user’s mobile device
As location awareness gains adoption, a common
framework to deliver services such as electronic queuing or
determining the nearest point of interest would need to be
made available in a standardized manner such that different
service providers can extend their services on a common
platform. Additionally, user’s privacy and security needs to
be maintained both in the context of anonymity as well as
being able to determine a user’s location without consent.
V. CONCLUSION
This paper discusses a few software implementations
which are recently available to develop location aware
applications. Furthermore, the paper discusses possible
implementation scenarios. The issues of privacy and
security normally associated with location aware
applications are not discussed in these implementation
scenarios and are left for future work. The potential and
value-added of location aware applications can now be
materialized through development on top of the platforms
provided by Intel and Microsoft for location awareness
technologies.
R
EFERENCES
[1] Seigo Ito, Nobuo Kawaguchi, “Bayesian Based Location Estimation
System Using Wireless LAN”, IEEE Proceedings of the 3rd Int’l
Conf. on Pervasive Computing and Communications Workshops,
2005.
[2] Place Lab, Intel Corporation. http://www.placelab.org
[3] Anthony LaMarca, Yatin Chawathe, Sunny Consolvo et al., “Device
Positioning Using Radio Beacons in the Wild”, Proceedings of
Pervasive Computing, 2005.
[4] Yu-Chung Cheng, Yatin Chawathe, Anthony LaMarca, John Krumm,
“Accuracy Characterization for Metropolitan-scale Wi-Fi
Localization”, Proceedings of MobiSys, Jan 2005.
[5] MapPoint Location Server. Microsoft Corporation.
http://www.microsoft.com/mappoint/products/locationserver/default.m
spx
[6] Alexander Leonhardi, Kurt Rothermel, “Architecture of Large Scale
Location Service”, Proceedings of the 22nd International Conference
on Distributed Computing Systems, 2002.
[7] Paul Hawking, Andrew Stein, John Zeleznikow, et al, “Emerging
Issues in Location Based Tourism Systems”, Proceedings of the
International Conference on Mobile Business, 2005.
[8] Jason Cheung, Peter Fotopoulos, Jeffrey Kalvass, Jimmy Wei,
“Mobile Access Queuing”, University of California Davis,
Unpublished.
[9] James Nord, Kare Synnes, Peter Parnes, Architecture for Location
Aware Applications”, Proceedings of the 35th Hawaii International
Conference on System Sciences, 2002.
[10] Maria Riaz, Saad Liaquat Kiani, Sungyoung Lee, Sang-Man Han,
Young-Koo Lee, “Service Delivery in Context Aware Environments:
Lookup and Access Control Issues”, Proceedings of the 11th IEEE
International Conference on Embedded and Real-Time Computing
Systems and Applications, 2005.
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Microsoft Corporation
  • Mappoint Location
  • Server