Location Based Services Mobile Computing CNT 55175564

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Location Based ServicesMobile Computing - CNT
5517-5564

• Dr. Sumi Helal
• Professor
• Computer Information Science Engineering
  Department
• University of Florida, Gainesville, FL 32611
• helal_at_cise.ufl.edu

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Reading Materials

• Paolo Bellavista, Axel Küpper and Sumi Helal
  Location Based Services Back to the Future,
  the Standards, Tools and Emerging Technologies
  Department, IEEE Pervasive Computing Magazine,
  Sumi Helal, Editor, Volume 7, Number 2,
  April-June 2008
• Roxin, A., Dumez, C., Wack, M., and Gaber, J.
  2008. Middleware models for location-based
  services a survey. In Proceedings of the 2nd
  international Workshop on Agent-Oriented Software
  Engineering Challenges For Ubiquitous and
  Pervasive Computing (Sorrento, Italy, July 06 -
  06, 2008). AUPC '08. ACM, New York, NY, 35-40.
• C. Lee, A. Helal and D. Nordstedt, "µJini Proxy
  Architecture for Impromptu Mobile Service
  Access," Proceedings of the Workshop on Next
  Generation Service Platforms for Future Mobile
  Systems (SPMS 2006). In conjunction with the
  IEEE/IPSJ International Symposium on Applications
  and the Internet (SAINT), Phoenix, Arizona,
  January 2006. (pdf)

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Overview

• What is LBS? What is impromptu LBS?
• Examples
• Why did LBS not take off for the past 10 years?
• LBS Evolution
• Todays LBS classification
• LBS Middleware
• Service Discovery
• Service Delivery
• Some ongoing research

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Location Based Services

• A service whose rendering depends on the location
  of the service requester, service provider or
  both
• Mobile, networked Applications
• Input geo references from Assisted GPS system
• Client/server interaction
• Output Location relevant Information
• Example weather, tourist information, ..

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Elements of LBS

• Querying
• Advertisement
• Discovery
• Delivery
• Localization Management
• No installs
• Lease / Release
• Location Privacy

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Impromptu LBS
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Impromptu LBS
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Impromptu LBS
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Why Difficult to Believe LBS did not take off?
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Great Phones/ Great B/W2.5-3G Mobile Phones
shown

• GPRS, EDVO, UMTS,
• 500-800 K speed
• Who needs Hot Spots!

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The WiMAX Possibility

• Wireless Mobile Broadband at 10-30 miles range
• The Fat Pipe problem. Mobile TV no thank you!

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Commoditization Pressure

• The Skype Phenomena
• VoIP as a cheaper mobile phone service
• Signs of commoditization of the Telecom Industry?
  ? pressure on Telecom to explore new sources of
  revenues ( New Services).

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Early LBS (1)

• Content-Centric
• Current LBSs are content-oriented and lack the
  logic necessary for user interactivity (no user
  models captured in the service)
• Content could be boring! And has limited impact
  as compared to interactions
• Content-centricity was not by choice, it was more
  of a constraint. Downloading content was what is
  available, and was challenging enough (e.g. WAP
  performance)

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Early LBS (2)

• Precision of the Localization subsystem
• Cellular triangulation useful for some
  applications but inadequate for others.
• On-board GPS (e.g., Assisted GPS) offers better
  accuracy, but does not work indoor.
• Locate nearest Pizza place! era of LBS
• Does not need accuracy
• Outdoor!

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Early LBS (3)

• Telecom-centric
• Localization data owned by Telco location based
  information provided by telco telco partners
  with other content providers (such as Verizon and
  Microsoft MSN never took off, even with a
  massive publicity campaign).
• The centricity and encumbrance by telecom proved
  to be non-scalable and actually an impedance to
  the much-anticipated proliferation of the elegant
  LBS concept

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The First FixFrom Content to Applications

• Redefining LBS to be a framework not an
  application.
• As an application, LBS, gets a location, passes
  it to an authoritative server (_at_telco), and then
  delivers back location relevant information to
  the target. This is one application very
  limiting.
• As a framework, LBS gets a location, passes it to
  servers owned or provided by participating
  businesses (small, medium, large, from any
  industry imaginable), and then delivers back
  location relevant services (applications) to the
  target. This is unlimited number of applications.
  This is very flexible and exciting!

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Requirement to the First FixImpromptu (flash)
Delivery of Applications.

• Middleware and intelligent markup languages
  should be developed to enable the development of
  extremely compact size code that takes a few
  second to download and a couple of seconds to get
  interpreted and run on a mobile target equipped
  with the middleware engine.
• Code not content compact code gets interpreted
  to native computations utilizing native
  resources.
• Net effect
• seconds instead of minutes in delivery time
• No installation, de-installation or management.
• Applications appear-disappear.

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The Second FixEnable Indoor Localization

• More investment in indoor localization
  technology.
• Standardizations
• Solve Privacy issues
• Bluetooth Example Through the creation of a new
  Legalized Snooping profile
• Snoop protocol
• Pay customer to snoop
• Access to customer profile
• On the fly tailored applications
• Other possibilities Ultra wideband, or even
  licensed frequencies.

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The Third FixAlter LBS Business Model

• Telco to sell and profit from basic services only
  (data pipe, SMS pipe, ..and perhaps application
  pipe in the future). Telco no longer define LBS.
• Empower small, medium and large size businesses
  to transact LBS directly with end users.
• Any business should be allowed to participate and
  offer LBS. A business should be able to develop
  LBSlets using simple LBS development kits.
• Businesses can host their own LBSs either
  directly or through a web hosting service.
• User to own and sell his/her LBS user profile.

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LBS Evolution
Integration of location data into social network
services
Merging of outdoor and indoor LBS applications
LBS features and supporting services
Location-based dating

• Introduction of finder LBSs
• Restaurants
• Filling stations
• ATMs

Google launches GoogleMaps
First Child tracking services
First commercial Proactive LBSs
Application-oriented LBSs
First location-based Mobile gaming
1996
2000
2004
2008
2012
FCC passed E-911 mandate
Mass market penetration of GPS-capable mobiles
Emergence of RFID
Deadline phase 1 of E-911
Launch of Galileo
First commercial WLAN fingerprinting systems
New middleware features for spam avoidance and
privacy preservation
Key technologies activities
Intro- duction of Android handset
First handset Supporting Java Location API
Introduction of 3G networks
Deadline phase 2 of E-911
First GPS capable iPhone
GPS works indoors
Emergence of common middleware for proactive,
cross-referencing, and multi-target LBSs
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LBS Evolution
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Service Discovery

• Impromptu service discovery and delivery
• Widespread use of diverse mobile devices
• Wireless hotspots and broadband coverage
• Location-based and other context-relevant
  services
• Most importantly the Business Opportunity
• Challenges of impromptu mobile services
• User mobility
• Service portability across a wide range of mobile
  devices
• Relevance and suitability avoiding the morass of
  the Web
• User Manageability
• Acceptable quality of service
• An effective infrastructure is a key to realize
  this vision
• Context-aware service discovery
• Device-independent service delivery

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Service Discovery Protocols

• Service discovery is relatively new (in the late
  1990s).
• IETF SLP, Sun Jini, UPnP, and Salutation
• Announce-listen model (Soft state model)
• Ad-hoc Service Discovery
• IBM DEAPSpace
• Konark Service Gossip Protocol LHD03HDV03
• Wide-area Service Discovery
• Wide-area extension to SLP (WASRV)
• Berkeley Secure Service Discovery Service (SSDS)

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Sever Selection Mechanisms

• Selection of the best among replicated services
• Availability, fault-tolerance, load-balance, and
  scalability
• Server-side approach
• HTTP redirect
• Network-side approach
• DNS round-robin, DNS LOC RR, DNS GL RR
• IP Anycast, Cisco DistributedRouter
• IETF RSerPool (Reliable Server Pooling)
• Client-side approach
• SmartClient

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Three-tier Mobile Service Discovery Architecture

• Provide the most appropriate service to mobile
  users by exploiting any meaningful context
  information
• Service classification by coverage

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Conceptual Model of the Three-tier Discovery
Architecture

• Different selection criteria
• Guided selection
• User transparency
• Scalability (Performance)

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Domain Discovery Sub-system

• On-campus registry hierarchy example

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Global Service Discovery

Domain hierarchy GSR-capable registry BA-capab
le registry
GSR
BA

Domain-3
GSR
Domain-2
BA
service
BA
BA
Client
Domain-1
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Service Delivery Technologies

• Over the Air Downloads (OTA)
• UI tailored to work on target device downloading
  the service
• Universal Interactions
• Device-Independent UI Languages
• W3C XForms, INCITS/V2 URC, XIML, UIML, CMU PUC
• UI Remoting Approaches
• UPnP Remote UI, ?Jini Proxy Architecture
• UI Authoring Styles (W3C DI)
• Single Authoring
• A single generic description (all-in-one
  approach)
• Multiple Authoring
• A UI for each type of client devices (Jini
  ServiceUI project)
• Flexible Authoring
• Customized UIs for popular platforms and
  automatically generated interfaces for rare
  platforms

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Java for Mobile Services

• Java technologies for service portability and
  dynamic service discovery
• J2ME
• Java runtime environments optimized for mobile
  devices
• Configurations CLDC and CDC
• Profiles MIDP, FP, PP, and other optional
  packages
• Jini
• Dynamic service discovery framework on top of
  Java RMI
• Jini Surrogate Architecture for resource-poor
  devices
• Jini requires J2ME CDC/RMI Profile as the minimal
  runtime environment

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?Jini Proxy Architecture
VTC-Based Service Delivery
?Jini Protocol
?Jini Proxy (VTC Service Delivery)
Mobile Clients
Standard Jini Protocol
Context-Aware Service Discovery
Enhanced Jini Protocol
Context-aware Jini Lookup Service
Service Providers
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?Jini Proxy Architecture

• ?Jini Proxy
• functions as a proxy to a Jini network w.r.t.
  service discovery
• serves client devices as VTC servers for service
  delivery
• Three delivery mode to bring discovered services
  to resource-constrained mobile devices
• Client executable mode
• VTC MIDlet emulation mode
• VTC J2SE emulation mode
• Capable of selecting the best adaptation
  depending on the service context

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Thin-Client Approach to Service Delivery

• VTC (Virtual Thin Client)-based adaptation
• Three delivery modes Client executable, MIDlet
  service emulation, J2SE service emulation
• Built on top of Sun Jini and ATT VNC
• Smart-phone client (J2ME capable phone)
• Four main components
• ?Jini Protocol
• Resident Client
• VTC
• ?Jini Proxy

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?Jini System Architecture
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MIDlet Emulator
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VTC non-MIDlet Emulation Mode
ZOOM
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Performance Measurement