Download - Location Based services
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Benghazi-Libya
University of BenghaziFaculty of Information Technology
Computer Networks & Communications Department
LOCATION BASED SERVICES
AUTUMN 2012 / 2013
Name: Faraj Ramadan Kassem ID: 415
Supervisor : Dr. Adel Aneiba
Benefits to Community
Car Tracking Personal Navigation News M-Commerce EmergencyChild Tracking
M-commerce: Mobile Commerce
1/23
Benefits to Community (Cont`d)Location Based Services
Maps & Navigation
Tracking Services
Information Services
Application
Maps Routing Assisted
Navigation
Friends & Family Finder
Traffic Vehicle
Tracking
City guides User
Generated Content (UGC)
Social Networks
Context Advertisements
2/23
Aim and Objectives
Outlines
Introduction
Comparison of Positioning Systems
LBS Components
Positioning Systems
Conclusion and Future Work
Privacy of LBS
3/23
Aim and ObjectivesAim :• To evaluate a Location Based Services (LBS) positioning techniques.
Objectives:
To investigate the characteristic of the LBS.
Gaining an understanding of components of LBS and underlying technologies.
To study the existing LBS systems.
Investigating the challenge of protecting the privacy of LBS users
To comparing between the LBS systems.
4/23
Services
Location + Requests
Services
Introduction
LBS Provider
LBS User
Location + Requests
LBS Application
5/23
LBS as an intersection of technologies
Introduction (cont`d) 7/23
LBS Architecture :
LBS Components
Location Collection Service (LCS)
GIS ProviderLocation Tracking
GISData
LBS Middleware
8/23
LBS Middleware Standards
LBS Components (Cont`d)
The Open Location Services (OpenLS) standard proposes
an overall system architecture for various components :
location collection services .
LBS application providers .
Geography Markup Language (GML): This is an XML-
based language for representing various geography data such as
points of interest.
Keyhole Markup Language (KML): This complements GML by
providing information about annotations and markings on maps
(visualization).
Three important standards (OpenLS, GML and KML)
9/23
• Why privacy is a concern with LBS ?
• Identification Requirements of LBS .
Anonymous LBSs.
Identity-driven LBSs.
Pseudonym-driven LBSs.
• Privacy Solutions
Anonymization.
Cryptographic Techniques.
Transformation of Location request data.
Privacy in LBS10/23
Evaluation of LBS Positioning Systems
• Cell of Origin (COO): This technique is used if the positioning system has a cellular structure.
• Time of Arrival (TOA): Time Difference of Arrival (TDOA).
• Angle of Arrival (AOA): If we use antennas with direction characteristics.
Basic Location Techniques
11/23
Triangulation:: needs two fixed positions (p1 and p2). , we measure the angle to the location u.
Trilateration:: also needs two fixed positions, but uses two distances to the unknown location.
Traversing: uses several distance–angle pairs. We start with a known point p1 and measure the bdistance and direction
Basic Location Techniques (Cont`d)
12/23
Satellite Basede.g. GPS
Network BasedGSM
Indoor PositioningInfrared , RFID & WLAN
Positioning Systems
GPS (Global Positioning System ) WLAN (Wireless Local Area Network RFID (Radio Frequency Identification ) GSM (Global System for Mobile)
13/23Evaluation of LBS Positioning Systems(cont`d)
1. Satellite Based Positioning
• Cover huge geographical areas.• Standalone infrastructure and terminal-based
Advantages High accuracy World-wide coverage
Disadvantages Positioning requires line-of-sight between satellite and receiver High power consumption at the receiver High operation costs
Examples GPS (Global Positioning System) Galileo
Evaluation of LBS Positioning Systems(cont`d)14/23
Principle of satellite positioning.
1. Satellite Based Positioning (cont’d)
The user knows the distance of the satellite to him, as well as the position of the satellite r =c*∆t
So he can calculate a radius is somewhere on. But he does not know where on the radius he is.
By looking at the intersection of the coverage radius of at least 3 satellites, he can discover
his exact position
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2. Network Based Positioning (e.g. Cellular Positioning)
Focuses on positioning services within the coverage area of a cellular network.
• Advantages• Good yield (in most cases even indoors).• Some positioning methods require either no or only minor modifications at mobile
devices (firmware upgrade).
Disadvantages High signaling overhead. Moderate accuracy.
Examples Cell-Id. Enhanced Observed Time Difference (E-OTD). Assisted GPS (A-GPS).
Evaluation of LBS Positioning Systems(cont`d) 16/23
Evaluation of LBS Positioning Systems(cont`d)3. Indoor Positioning (e.g. WLAN Positioning)
Deployment in buildings, university campuses, and company premises Stand-alone and integrated infrastructures (e.g., RFID vs. WLAN)
AdvantagesLow power consumptionHigh accuracy
DisadvantagesProprietary systems, i.e., no standardization
Examples
WLAN positioningUltrasound positioningRFID positioning
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Evaluation of LBS Positioning Systems(cont`d)
Position can be detected by measuring Signal Strength of all wireless LAN access
points.
Wi-Fi: Wireless Fidelity
3. Indoor Positioning (e.g. WLAN Positioning)
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3. Indoor Positioning (cont’d)(Infrared , Ultra Sound , Video and RFID)
Infrared(Active Badge)
Ultrasound Video RFID
19/23
Precision Medium Mechanism Tracking/Positioning
Category Name
25 m Radio TOA Positioning Satellite GPS
Depends on Cell Density 40-400
Radio COO, AOA, TOA
Both Network GSM E-
OTD
Dependent on Wi-Fi AP density 3 m
Radio Signal Strength
Positioning Indoor Wi-Fi
Cell Radio COO Tracking Indoor RFID
Comparison of positioning Systems 20/23
Conclusion and Future Work
Many LBS applications use GPS to determine the current location.
however: It only works outdoors because the receiver must have a direct view
to at least four GPS satellites.
no positioning system is accessible everywhere.
If a service wants to have high coverage, it has to rely on several positioning
techniques.
Conclusion:
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More investigations are required to assess the behavior of the LBS under
different positioning techniques.
To explore the limitations of the LBS paradigm .
To develop real LBS systems which are more intelligent and accurate.
More investigations are required to assess user experiences in regard to
privacy and security.
Conclusion and Future Work (cont`d)Future Work:
22/23
References[1] L. Perusco and K. Michael, "Control, Trust, and Security: Evaluating Location-Based Services", IEEE Technology
and Society Fvlagazine, Spring 2007
[3] M. Takeda, "Will GPS Mobile Phones Become the Driving Force in the GPS Applications Market?", nG Mobile in
Japan and Asia, 1(7), July 22, 2002.
[4] J. Green, D. Betti, and J. Davison. Mobile Location Services: Market Strategies, OVUM, London, 2000.
[5] G. Alonso, F. Casati, H. Kuno, and V. Machiraju. Web Services: Concepts, Architectures and Applications. Springer
Verlag Publishers, Berlin/Heidelberg, 2003.
[6] I. Burcea, H.-A. Jacobsen, E. DeLara, V. Muthusam, and M. Petrovic. "Disconnected Operations in
Publish/Subscribe." IEEE Mobile Data Management, IEE Publication, pages 39–50, 2004.
[7] H.-A. Jacobsen. "Middleware Services for Selective and Location-based Information Dissemination in Mobile
Wireless Networks." Advanced Topic Workshop on Middleware for Mobile Computing, November 12–16, 2001.
[8] K. V. B. Andersen, M. Cheng, R. Klitgaard-Nielsen. "Online Aalborg Guide: Development of a Location-Based
Service." Student Report, 102 pages, Aalborg University, 2003.
[9] K. Dueker and J. A. Butler. "GIS-T Enterprise Data Model with Suggested Implementation Choices," Journal of the
Urban and Regional Information Systems Association, 10(1):12–36, 1998.
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Any questions?Thank you