LocationBased Services

1
Location-Based Services

• Introduction to Mobile Technologies
• Vespucci Summer School

2
Introduction to Mobile Technologies

• Cellular systems
• WLANs
• Operating systems
• Messaging
• Mobile Internet
• Java
• Voice XML
• SyncML
• Bluetooth
• Positioning

3
Cellular Systems

• Cellular phones
• Radio-based technology including circuit board,
  liquid crystal display, keyboard, microphone,
  speaker, battery and SIM cards (removable disks
  that are inserted into GSM cell phones)
• Radio wave is an electromagnetic wave propagated
  by an antenna
• GSM picks up signals in the 900MHz, 1800MHz and
  1900MHz range

4
Cellular Systems

• Cells and base stations
• Division of space into cells
• Each cell has a base station (tower and radio
  equipment)
• Base stations coordinate themselves to offer
  access to the network to users on the move

5
Cellular Systems

• Architecture of a GSM Network - Subsystems
• Mobile Stations are the mobile phones
• Base Station Sub-system provides the air link for
  the MS
• Network Sub-System connects calls between network
  users
• Operation Sub-System provides network
  administrators with remote network monitoring and
  management capabilities

6
Cellular Systems

• Architecture of a GSM Network - Subsystems
• Mobile Stations - MS Subscriber Identity Module
  (SIM) Mobile Equipment (ME)
• Base Station Subsystem - BSS Base Station
  Controller (BSC) (includes the TransCoder Unit
  (TCU)) Base Transceiver System (BTS)
• A BTS serves a cell or a small number of cells
  and is responsible for the communication with the
  MS.
• Several BTSs are controlled by a BSC, which is
  responsible for the communication with the NSS
  and OSS

7
Cellular Systems

• Architecture of a GSM Network - Subsystems
• Network Sub-System - NSS connects calls among
  mobile subscribers of the same network or to
  other networks
• Composed of several Mobile Switching Centres
  (MSC) in conjunction with location registers
  (Home Location Register HLR, Visitor Location
  Register VLR) and authentication centres (AUC).
• Operations and Maintenance Centre (OMC) provides
  the network with remote monitoring and
  maintenance as well as with alarm functions and
  event logging

8
Cellular Systems

• Architecture of a GSM Network - Subsystems

9
Cellular Systems

• GSM Network - Handovers
• As you move toward the edge of your cell, its
  base station notes that your signal is
  diminishing.
• The base station in the cell you are toward sees
  your phones signal strength increasing.
• The two base stations coordinate with each other
  and, at some point, your phone switches to the
  new cell.
• This is process is called a handover and must
  occur before the perceived quality of the
  communication falls under an admissible threshold.

10
Cellular Systems

• Cellular access technologies
• Time Division Multiple Access (TDMA)
• A narrow band that is 30 kHZ wide and 6.7
  millisecond long is split time-wise into three
  time slots.
• Each conversation gets the radio for one-third of
  the time. Voice data is converted into digital
  information and compressed so that it takes up
  less transmission space.
• TDMA is used as the access technology for Global
  System for Mobile communications (GSM)

11
Cellular Systems

• Cellular access technologies
• Time Division Multiple Access (TDMA)

12
Cellular Systems

• Cellular access technologies
• GPRS (General Packet Radio Service)
• Packet radio upgrade to GSM - IP-based data
  transmission
• Can have speeds of up to 114kbps
• Makes it possible for users to make telephone
  calls and transmit data at the same time
• GPRS systems enable constant access to the
  Internet, and send and receive multimedia
  messages (MMS)
• Performance degrades with number of users
  (bandwidth shared with voice calls)
• Known as 2.5G Services similar to those
  proposed for 3G
• Always On - Pay what you use users pay data
  transfer, not air time

13
Cellular Systems

• Cellular access technologies
• Code Division Multiple Access (CDMA)
• Digital wireless technology that allows multiple
  users to share radio frequencies at the same time
  without interfering with each other. A telephone
  or data call is assigned a unique code.
• High speed CDMA or Wideband CDMA will be used in
  Europe for the Universal Mobile Telephony Systems
  (UMTS) and in Japans third generation. W-CDMA
  was co-developed by NTT DoCoMo.

14
Cellular Systems

• Cellular access technologies
• Universal Mobile Telephony Systems (UMTS)
• UMTS or the third generation mobile telephony
  (3G) are generic names of mobile technologies
  that will use infrastructure networks, handsets,
  base stations, switches and other equipment to
  allow mobiles to offer high-speed Internet
  access, data, video and CD-quality music
  services.
• UMTS will provide speeds of up to 2 Megabits per
  second

15
Cellular Systems

• Main actors
• Major operators (Vodafone, T-Mobile, TIM,
  Telefonica, Orange, BT, NTT, China Mobile,
  Verizon)
• Major infrastructure providers (Alcatel,
  Ericsson, Siemens, Nokia, Nortel, Lucent,
  Motorola)
• Major device makers (Nokia, Motorola, Siemens,
  Sony Ericsson, Samsung)
• Technology and standards (GSM Association, Open
  Mobile Alliance, UMTS Forum, Symbian)
• http//www.gsmworld.com
• http//www.wapforum.org
• http//www.umts-forum.org
• http//www.symbian.com

16
Wireless Local Area Networks - WLANs

• Based on the IEEE 802.11 standard.
• There are three physical layers for WLANs two
  radio frequency specifications (RF - direct
  sequence and frequency hopping spread spectrum)
  and one infrared (IR).
• Most WLANs operate in the 2.4 GHz license-free
  frequency band and have throughput rates up to 2
  Mbps. The 802.11b standard is direct sequence
  only, and provides throughput rates up to 11
  Mbps.
• 802.11g, is now emerging. It operates in the 5
  GHz license-free frequency band and provides
  throughput rates up to 54 Mbps.
• http//www.80211hotspots.com/ (location of
  wireless access points around the world)

17
Wireless Local Area Networks - WLANs

• Typical Architecture

18
Wireless Local Area Networks - WLANs

• WLAN Configurations
• Simple, independent, peer-to-peer connections
  between a set of personal computers

19
Wireless Local Area Networks - WLANs

• WLAN Configurations
• Intra-building infrastructure networks

20
Wireless Local Area Networks - WLANs

• WLAN Configurations
• Point-to-Point Point-to-Multipoint Wireless
  Solutions
• A point-to-point solution (Fig.4) is used to
  bridge between two local area networks, and to
  provide an alternative to cable between two
  geographically distant locations (up to 50 kms)
• Point-to-multi-point solutions connect several,
  separate locations to one single location or
  building

21
Operating Systems

• Symbian
• Supports 3G mobile phones, mobile messaging
  (including MMS), mobile networking (Internet
  Protocol version 6) and C and Java development
• It also supports
• SyncML, allowing convenient over the air (OTA)
  synchronization of data
• several audio/image formats
• low level APIs for game developers (incl.
  Bluetooth control for multi-player games)
• encryption and certificate management, and secure
  communications protocols
• www.symbian.com

22
Operating Systems

• Symbian
• The newest Nokia smart phones provide the Series
  60 platform which runs on top of the Symbian OS
• Publicly announced products based on Symbian OS
  for 2.5 and 3G networks include the BenQ P30,
  Samsung SGH-D700, Siemens SX-1, NTT DoCoMo FOMA
  F2051 and F2021V, both built by Fujitsu, Sony
  Ericsson P800, Nokia 9200 Communicator, 7650,
  6600, 3650 and N-Gage.

23
Operating Systems

• Symbian Phones

24
Operating Systems

• Symbian OS is characterised by
• Integrated multimode mobile telephony Symbian
  OS integrates the power of computing with mobile
  telephony, bringing advanced data services to the
  mass market
• Open application environment Symbian OS enables
  mobile phones to be a platform for deployment of
  applications and services (programs and content)
  developed in a wide range of languages and
  content formats
• Open standards and interoperability With a
  flexible and modular implementation, Symbian OS
  provides a core set of application programming
  interfaces (APIs) and technologies that is shared
  by all Symbian OS phones. Key industry standards
  are supported

25
Operating Systems

• Symbian OS is characterised by
• Multi-tasking Symbian OS is based on a micro
  kernel architecture and implements full
  multi-tasking and threading. System services such
  as telephony, networking middleware and
  application engines all run in their own
  processes
• Fully Object-oriented and component based The
  operating system has been designed from the
  ground up with mobile devices in mind, using
  advanced OO techniques, leading to a flexible
  component based architecture
• Flexible user interface design By enabling
  flexible graphical user interface design on
  Symbian OS, Symbian is fostering innovation and
  is able to offer choice to manufacturers,
  carriers, enterprises and end-users. Using the
  same core operating system in different designs
  also eases application porting for third party
  developers
• Robustness Symbian OS maintains instant access
  to user data. It ensures the integrity of data,
  even in the presence of unreliable communication
  and shortage of resources such as memory, storage
  and power.

26
Operating Systems

• Symbian OS Version 7.0s

27
Operating Systems

• Symbian OS Version 7.0s Key Features
• Provides a rich core of application programming
  interfaces that are common to all Symbian OS
  phones
• Suite of application engines the suite includes
  engines for contacts, schedule, messaging,
  browsing, utility and system control OBEX for
  exchanging objects such as appointments (using
  the industry standard vCalendar) and business
  cards (vCard) integrated APIs for data
  management, text, clipboard and graphics
• Browsing a WAP stack is provided with support
  for WAP 1.2.1 for mobile browsing
• Messaging multimedia messaging (MMS), enhanced
  messaging (EMS) and SMS internet mail using
  POP3, IMAP4, SMTP and MHTML attachments fax
• Multimedia audio and video support for
  recording, playback and streaming image
  conversion

28
Operating Systems

• Symbian OS Version 7.0s Key Features
• Graphics direct access to screen and keyboard
  for high performance graphics accelerator API
• Communications protocols wide-area networking
  stacks including TCP/IP (dual mode IPv4/v6) and
  WAP, personal area networking support include
  infrared (IrDA), Bluetooth and USB
  Quality-of-Service (QoS) on GPRS/UMTS networks
• Mobile telephony Symbian OS v7.0s is ready for
  the 3G market with support for GSM circuit
  switched voice and data (CSD and EDGE ECSD) and
  packet-based data (GPRS and EDGE EGPRS) CDMA
  circuit switched voice, data and packet-based
  data (IS-95, cdma2000 1x, and WCDMA) SIM, RUIM
  and UICC Toolkit Other standards can be
  implemented by licensees through extensible APIs
  of the telephony subsystem
• International support conforms to the Unicode
  Standard version 3.0

29
Operating Systems

• Symbian OS Version 7.0s Key Features
• Data synchronization over-the-air (OTA)
  synchronization support using SyncML PC-based
  synchronization over serial, Bluetooth, Infrared
  and USB a PC Connectivity framework providing
  the ability to transfer files and synchronize PIM
  data
• Security full encryption and certificate
  management, secure protocols (HTTPS, WTLS and SSL
  and TLS), WIM framework and certificate-based
  application installation
• Developing for Symbian OS content development
  options include C, Java (J2ME) MIDP 2.0 and
  PersonalJava 1.1.1a (with JavaPhone 1.0 option),
  and WAP tools are available for building C and
  Java applications and ROMs with support for
  debugging
• User Inputs generic input mechanism supporting
  full keyboard, 0-9 (numeric mobile phone
  keypad), voice, handwriting recognition and
  predictive text input.

30
Operating Systems

• Multimedia in Symbian OS v7.0s

31
Operating Systems

• Smartphone
• Windows Powered environment using familiar
  Microsoft software
• Outlook capabilities, Windows Media Player,
  infrared beaming, and MSN Messenger
• Programmable using Microsoft Mobile Development
  Toolkit (incl. in The Smartphone Developer Kit)
• www.microsoft.com/mobile/smartphone/default.asp

32
Operating Systems

• Smartphone

33
Messaging

• Short Message Service (SMS)
• Up to 160 characters of text in length words or
  numbers or an alphanumeric combination
• Non-text based short messages (for example, in
  binary format) are also supported. These are used
  for ringtones and logos services for instance
• SMS is a store and forward service short
  messages are not sent directly from sender to
  recipient, but always via an SMS Center (SMSC)
• Short messages can be sent and received
  simultaneously with GSM voice, Data and Fax calls

34
Messaging

• Short Message Service (SMS)
• Sending an SMS
• The message originator addresses the short
  message to the receiver.
• The phone contains information about SMSC (SMS
  Center), and the message is sent there.
• SMSC attempts to forward the message to the
  receiver.

35
Messaging

• Multimedia Message Service (MMS)
• The data speed in the networks must be at least
  14.4 kbit/s for carrying MMS messages.
• MMS messages are currently between 30 kB and 100
  kB in size
• They can contain still images (JPEG, GIF, WBMP),
  text, voice (AMR voice), audioclips or
  videoclips 
• MMS transport is done using WAP over GPRS (or
  CSD) transport. WAP push features are used to
  deliver the message from server to receiving
  phone.

36
Messaging

• Multimedia Message Service (MMS)
• MMS can then either be sent to a phone (via a
  notification message) or sent to the recipient's
  email account.
• Content of MMS messages has been defined by the
  MMS Conformance Specification version 2.0.0
  written by the MMS Interoperability Group (CMG,
  Comverse, Ericsson, Logica, Motorola, Nokia,
  Siemens and Sony Ericsson).
• Specifies SMIL 2.0 Basic profile for the
  presentation format, an XML-based standard that
  defines how the multimedia elements are
  coordinated.
• Multimedia Messaging Service Center (MMSC) is the
  store and forward network element that delivers
  the MMS messages from the sender to the
  recipient.
• http//www.symbian.com/technology/mms.html
• www.forum.nokia.com

37
Messaging

• Multimedia Message Service (MMS)

38
Messaging

• Multimedia Message Service (MMS)
• Sending an MMS
• The message originator addresses the multimedia
  message to the receiver.
• The terminal contains information about MMSC (MMS
  Center), and the message is sent there.
• MMSC attempts to forward the message to the
  receiver.
• That Simple?

39
Messaging

• Multimedia Message Service (MMS)
• Types of MMS transactions
• Mobile Originated Transactions (MO)
• Mobile Terminated Transactions (MT)
• Application Originated Transactions (AO)
• Application Terminated Transactions (AT)

40
Messaging

• Multimedia Message Service (MMS)
• Mobile Originated Transactions
• In mobile originated (MO) transactions, the
  sender is a Mobile Station (MS).
• The message can terminate directly to another MS,
  or possibly go to an e-mail address. If a picture
  has to be converted into another format (for
  example from JPEG to GIF), it can be sent to an
  application that does the conversion. After the
  conversion, the message is sent to its
  destination.

41
Messaging

• Multimedia Message Service (MMS)
• Mobile Terminated Transactions
• In mobile terminated (MT) transactions, the
  message is sent to an MS.
• The originator of the message can be another MS
  or an application, for example a Web-based
  picture-service application.

42
Messaging

• Multimedia Message Service (MMS)
• Application Originated Transactions
• In application originated (AO) transactions, the
  sender is an application.
• The message can be terminated directly to an MS
  or to another application.
• The message can be processed in one or more
  applications before it is sent to the receiving
  MS.

43
Messaging

• Multimedia Message Service (MMS)
• Application Terminated Transactions
• In application terminated (AT) transactions, the
  message receiver is an application.
• The message originator can be an MS or another
  application, e.g., if a message was sent for
  JPEG-to-GIF conversion before being sent to the
  shoebox storage of the TGW.

44
Mobile Internet

• Wireless Application Protocol
• WAP replaces a Web browser with a WAP browser,
  which can also request data from a Web site.
• A WAP browser requires a WAP gateway an
  intermediary between the mobile and Internet
  networks.
• When placed between a WAP browser and a Web
  server, it takes care of the necessary binary
  encoding of content and can also translate
  Wireless Markup Language (WML) from HTML.
• WML is a markup language based on XML that was
  developed and is maintained by the WAP Forum
• http//www.wapforum.org

45
Mobile Internet

• WAP Evolution
• WAP is a global standard for mobile Internet
  applications and browsing.
• Functionally similar to the WWW, it is designed
  to accommodate small devices with limited memory
  and small screens, as well as low bandwidth
  connections to the Internet that may be
  unreliable and have high latency.
• The first generation of WAP specifies an
  application environment including WML 1.x and a
  stack of optimized communication protocols.

46
Mobile Internet

• WAP Evolution
• For mobile devices, the future of WAP lies in its
  close alignment with widely accepted Internet
  standards.
• The former WAP Forum and the World Wide Web
  Consortium (W3C) have successfully defined mobile
  Internet standards over a period of several
  years.
• To enable the convergence of mobile and wired Web
  content development, the WAP Forum adopted the
  XHTML standard with Cascading Style Sheets (CSS)
  from the W3C as the basis for WAP 2.0.
• Since mid-2002, the WAP Forum's specification
  work is being continued in Open Mobile Alliance
  (OMA).
• The transition to XHTML MP (Mobile Profile) and
  WAP CSS strengthens the mobile browsers position
  within the Internet mainstream and allows for a
  far greater range of presentation design and
  formatting possibilities than previously possible.

47
Mobile Internet

• WAP Evolution
• WML
• WML is a markup language based on the Extensible
  Markup Language (XML).
• The official WML specification was initially
  developed and maintained by the WAP Forum, an
  industry-wide consortium founded by Nokia,
  Openwave, Motorola, and Ericsson.
• HTML
• Hypertext Markup Language (HTML) is a markup
  language used to create hypertext documents that
  are portable from one platform to another.
• HTML documents are SGML (Standard Generalized
  Markup Language) documents with generic semantics
  that are appropriate for representing information
  from a wide range of applications. HTML has been
  the lingua franca of WWW publishing.

48
Mobile Internet

• WAP Evolution
• XHTML MP
• XHTML, according to the W3C, represents the first
  major change to HTML since HTML 4.0 was released
  in 1997.
• The latest version of HTML (Version 4.1) forms
  the basis of XHTML all tag definitions and
  syntax are the same. XHTML simply adds modularity
  and enforces strict adherence to language rules.
• As a result, XHTML brings clean structure to Web
  pages, which is especially important given the
  small screens and limited power of mobile
  devices.
• W3C is recommending XHTML for all future Web
  development for desktops, as well as all other
  devices, including mobile handsets.

49
Mobile Internet

• WAP Evolution
• XHTML MP XHTML Basic
• Is the mobile version of XHTML 1.1.
• Designed for Web clients that do not support the
  full set of XHTML features, for example, Web
  clients such as mobile phones, PDAs, pagers, and
  set-top boxes.
• XHTML MP is a strict subset of XHTML, starting
  with XHTML Basic and adding a few elements and
  attributes from full XHTML 1.1 that are useful in
  mobile browsers including additional presentation
  elements and support for internal style sheets.

50
Mobile Internet

• WAP Evolution
• WAP CSS
• Cascading Style Sheets describe how documents are
  presented on screen in the browser.
• CSS separates the presentation from the content.
  Changes to the presentation can be made in the
  style sheet and the changes are automatically
  reflected throughout the entire document (like
  the Master slide in this ppt).
• WAP CSS is the mobile version of CSS defined by
  OMA.
• It is a subset of CSS, omitting features that are
  not appropriate for very small devices and adding
  a few WAP-specific extensions to CSS.

51
Mobile Internet

• WAP Evolution
• WML 1.x Compatibility Extensions
• The WML 2.0 specification defines WML 1.x
  compatibility extensions, which are used to
  achieve backward compatibility instead of
  implementing full WML 1.x functionality.
• These extensions make it possible to use WML 1.x
  specific features in WAP 2.0-compliant clients
  that do not have dual browsers supporting both
  XHTML MP and WML 1.x.
• Figure in the next slide displays the
  relationships between markup languages.

52
Mobile Internet

• WAP Evolution

53
Mobile Internet

• WAP - Evolution

54
Mobile Internet

• Comparing WML 1.X XHTML MP CSS

55
Mobile Internet

• But do not forget
• A good mobile service is not dependent on the
  technology behind the service.
• Despite the standard used, differences are based
  on smart design, a strong brand, enhanced
  services, and the ability to listen to the
  consumer's needs.

56
Mobile Internet

• Scalable Applications
• In addition to the availability of various markup
  languages, there is also a broad selection of
  terminals with different screen sizes and
  capabilities.
• Therefore, it is wise to create applications that
  are not tied to any specific screen size or UI
  category.
• When designing an application, these two aspects
  need to be considered
• 1. The independence of the markup language
• 2. The independence of the devices display
  features
• The result will be applications that are scalable
  and rich. The biggest advantage of scalability in
  this case is that developers are able to generate
  the same content to a new markup language and
  display it on different devices with specific
  display capabilities.

57
Mobile Internet

• Scalable Applications

58
Mobile Internet

• CSS How do they work?
• 1. Browser fetches the first page of the
  application.
• 2. Server returns the content page.
• 3. Browser fetches the style sheet.
• 4. Server returns the appropriate style sheet for
  the browser type and the style sheet is cached in
  the browser so all subsequent pages are rendered
  immediately.
• 5. Browser fetches subsequent pages.

59
Mobile Internet

• CSS How do they work?
• Even though the content for both wired and
  wireless Internet is authored with XHTML, it is
  good to remember that not all Web content becomes
  directly mobile just by changing the style sheet.
• The benefit is that the same standard can be used
  for creating mobile services.
• However, the services need to be designed and
  defined separately from Web applications due to
  the different uses and display and bandwidth
  differences.
• XHTML is only the presentation layer of the
  service, and good mobile applications also need
  working functional logic.
• In addition, wireless applications must be
  practical for mobile use.

60
Mobile Internet

• Delivering Mobile Content
• XHTML MP content and WAP CSS do not require
  anything from WAP gateways, because there is no
  need for encoding.
• XHTML content goes through the gateway in text
  format, unlike WML, which is binary encoded.
• WAP gateways are still required because in the
  first phase of evolution towards next-generation
  mobile browsing, XHTML enabled terminals use the
  WAP stack for the transport, meaning that XHTML
  is delivered to the terminal using the WAP stack.
• In phase 2, the TCP/IP stack is used, and then an
  update is needed to the WAP gateway to support
  TCP/IP.
• In true WAP 2.0 architecture (XHTML MP content
  over TCP/IP stack) the role of the WAP gateway
  changes to WAP 2.0 proxy, enabling, for example,
  subscriber identification, service access
  control, privacy, charging, push services.

61
Mobile Internet

• Delivering Mobile Content

62
Mobile Internet

• Links
• Browsing on Mobile Devices, http//www.forum.nokia
  ./documentscom
• Introduction to WAP over GPRS, http//www.forum.no
  kia.com/documents
• Nokia Mobile Internet Toolkit XHTML Guidelines,
  http//www.forum.nokia./documents.com
• WAP 2.0 Specifications, http//www.wapforum.org/wh
  at/technical.htm
• XHTML Basic Specification, http//www.w3.org/TR/20
  00/REC-xhtml-basic-20001219/
• XHTML Media Types, http//www.w3.org/TR/xhtml-medi
  a-types/

63
JAVA J2ME

• J2ME Java 2 Micro Edition
• Javas J2ME technology enables the download of
  life management tools, information tools, and
  interactive games.
• Applications can be searched using the wireless
  application protocol (WAP) browser, and bookmarks
  and push messages are provided to direct the user
  to sites with Java applications.
• http//wireless.java.sun.com/j2me/index.html

64
JAVA J2ME

• J2ME Java 2 Micro Edition
• MIDP
• The Mobile Information Device Profile (MIDP),
  combined with the Connected Limited Device
  Configuration (CLDC), is the Java runtime
  environment for today's mobile information
  devices (MIDs) such as phones and entry level
  PDAs.
• MIDP provides the core application functionality
  required by mobile applications - including the
  user interface, network connectivity, local data
  storage, and application lifecycle management -
  packaged as a standardized Java runtime
  environment and set of Java APIs.

65
JAVA J2ME

• J2ME MIDP

66
JAVA J2ME

• J2ME MIDP
• Widely adopted as the platform of choice for
  mobile applications
• Deployed globally on millions of mobile phones
  and PDAs and supported by Java Technology
  Integrated Development Environments (IDEs).
• MIDP applications are installed and run locally
  on the mobile devices
• Can operate in both networked and disconnected
  mode
• The GUI is optimized for small displays

67
JAVA J2ME

• J2ME MIDP
• MIDP UI functionality includes pre-defined
  screens for displaying and selecting lists,
  editing text, popping up alert dialogs, and
  adding scrolling tickers.
• Forms
• Screens including any number of pre-defined
  items images, read-only or editable text fields,
  editable date and time fields, charts, and choice
  groups
• Any custom items added by developers to provide
  unique functionality and graphics

68
JAVA J2ME

• J2ME MIDP
• Multimedia Games
• Low-level API complements high-level API giving
  developers greater control of graphics and inputs
  when needed.
• Game API
• Game-specific functionality that takes advantage
  of native device graphics capabilities. Exs
• Sprites (bitmaps that can have transparency and
  be manipulated on the screen).
• Tiled layers
• Built-in audio provides support for tones, tone
  sequences and WAV files
• Mobile Media API (MMAPI) optional package for
  MIDP to add video and other rich content

69
JAVA J2ME

• J2ME MIDP
• Connectivity
• MIDP enables truly networked, event-driven
  applications.
• Supports leading standards HTTP, HTTPS, and
  serial port communications, among others.
• Wireless Messaging API (WMA) optional package
• Supports SMS and Cell Broadcast Service (CBS)
  capabilities of GSM and CDMA networks
• Server push model
• A push registry keeps track of applications
  registered to receive inbound information from
  the network
• When info arrives, the device decides whether to
  start the app based on user preferences
• Enables developers to include alerts, messaging
  and broadcast in MIDP applications and to take
  advantage of the event-driven capabilities of
  devices and networks

70
JAVA J2ME

• J2ME MIDP
• OTA Provisioning of Applications
• Major benefit of MIDP is the ability to
  dynamically deploy and update apps Over The Air.
• The MIDP specification defines how apps are
  discovered, installed, updated and removed on
  mobile devices.
• MIDP enables a service provider to identify which
  apps will work on a mobile device and obtain
  satus reports after installation, update or
  removal.

71
Voice XML

• Voice Extensible Markup Language (Voice XML)
• Designed for creating audio dialogs that feature
  synthesized speech, digitized audio, recognition
  of spoken and recording of spoken input, and
  telephony
• http//www.voicexml.org/

72
SyncML

• SyncML (based on XML) is the industry standard
  for universal synchronization of remote data and
  personal information across multiple networks,
  platforms and devices.
• It enables over the air (OTA) synchronization of
  data between devices.
• http//www.syncml.org

73
Bluetooth

• Bluetooth is a technology specification for small
  form factor, low-cost, short-range wireless links
  between mobile personal computers, mobile phones,
  and other portable handheld devices, and
  connectivity to the Internet.
• Bluetooth covers a range of up to 100 meters in
  the unlicensed 2.4GHz band.
• Because IEEE 802.11b WLANs also operate in the
  same band, there are interference issues to
  consider.
• As current WLANs are migrating to the 5 GHz band
  (IEEE 802.11g), this problem will be minimized.
• http//www.bluetooth.com/

74
Bluetooth

• Bandwidth
• Maximum gross bit rate is 1Mbps, although
  protocol overhead limits the net throughput to
  722Kbps for asynchronous transfer and 433Kbps for
  symmetric transfer
• Link Types
• Synchronous Connection-Oriented (SCO)
• Especially suitable for circuit-switched services
  (e.g. Voice) where very low delay and high QoS is
  required.
• The channels offered are symmetric (same speed in
  both directions) and synchronous (both parties
  know exactly when the next packet will come).

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Bluetooth

• Link Types (...cont.)
• Asynchronous Connection-Less (ACL)
• More efficient for data transfer and other
  asynchronous services
• This link offers packet switching and
  transmission slots are not reserved but rather
  are granted by a polling access scheme.
• A Piconet is a collection of up to 8 BT units
  where one is a master unit that controls the
  transmission and hopping scheme.
• The master indicates to a slave that it wants to
  send and the slave then receives.
• Slaves can send on slots only when they are in
  agreement with the master.

76
Bluetooth

• Link Types (...cont.)
• One connection can contain several links of
  either type
• Two phones can maintain a voice conversation
  while simultaneously exchanging data.
• Using a Piconet one master could maintain various
  SCO and ACL connections with several slaves
• 3 voice call limit within a Piconet

77
Bluetooth

• Piconet Scatternet
• One device can also be connected in two or more
  piconets. The set-up is called scatternet.
• A device can, however, only be a master to one
  piconet at a time.
• Support for hold, park, or sniff mode is needed
  for a device to be part of the scatternet.
• In these modes a device does not actively
  participate in a piconet, leaving time for other
  activities such as participating in another
  piconet, for example.
• The master/slave roles are not necessarily fixed
  and can also be changed during the connection if,
  for example, the master does not have enough
  resources to manage the piconet.
• Master/slave switch is also needed in the
  scatternet. Master/slave switch support is not
  mandatory.
• Most of current Bluetooth implementations support
  piconets only. Point-to-multipoint support
  depends on the implementation.

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Bluetooth

• Piconet Scatternet
• a) Point-to-point connection between two devices
• b) Point-to-multipoint connection between a
  master and three slaves
• c) Scatternet that consists of three piconets

79
Bluetooth

• Bluetooth in the home

80
Bluetooth

• Bluetooth on the road

81
Bluetooth

• Frequency Hopping
• Bluetooth technology uses a frequency hopping
  technique, which means that every packet is
  transmitted on a different frequency.
• In most countries, 79 channels can be used. With
  a fast hop rate (1600 hops per second), good
  interference protection is achieved.
• Another benefit is a short packet length. If some
  other device is jamming the transmission of a
  packet, the packet is resent in another frequency
  determined by the frequency scheme of the master.
• This scenario is depicted in the next Figure
  where packets of device 1 (colored packets) and
  device 2 (banded packets) are trying to use the
  same frequency.
• Note that this case only refers to situations
  where there are two or more simultaneous active
  piconets or a non-Bluetooth device using the same
  frequency in range. The error correction
  algorithms are used to correct the fault caused
  by jammed transmissions

82
Bluetooth

• Frequency Hopping

83
Bluetooth

• Frequency Hopping
• Subsequent time slots are used for transmitting
  and receiving.
• The nominal slot length is 625 µs. A packet
  nominally covers a single slot, but can be
  extended to cover three or five slots, as
  depicted in the next Figure.
• In multi-slot packets the frequency remains the
  same until the entire packet is sent.
• When using a multi-slot packet, the data rate is
  higher because the header and a 220 µs long
  switching time after the packet are needed only
  once in each packet.
• On the other hand, the robustness is reduced in
  a crowded environment the long packets will more
  probably be lost

84
Bluetooth

• Frequency Hopping
• Three-slot and five-slot long packets reduce
  overhead compared to one-slot packets. 220 µs
  switching time after the packet is needed for
  changing the frequency.

85
Bluetooth

• Connection Establishment
• The connection to a desired device is made by a
  page message.
• If the address of the recipient is unknown, an
  inquiry message is needed before paging.
• Before any connections are made, all units are in
  standby mode. A unit in a standby mode wakes up
  every 1.28 seconds to listen to page/inquiry
  messages.
• Each time a unit wakes up, it listens on one of
  the 32 defined hop frequencies.

86
Bluetooth

• Connection Establishment
• The page message will be sent on 32 different
  frequencies.
• Initially the message is sent on the first 16
  frequencies, 128 times, and if no response is
  received, the master sends a page message on the
  remaining 16 frequencies, 128 times.
• The maximum connection time is 2.56 seconds
• When paging, the master must know the slaves
  Bluetooth address and system clock to calculate
  the proper access code and the wake-up sequence
  phase. That information was provided in the
  inquiry process.
• In inquiry, the master sends an inquiry access
  code, and other devices respond with their
  identity and system clock.

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Bluetooth

• Connection Establishment
• In connection state, the Bluetooth unit can be in
  several modes of operation. Sniff, hold, and park
  modes are used to save power or to free the
  capacity of a piconet
• Active mode In the active mode, the Bluetooth
  unit actively participates on the channel.
• Sniff mode In the sniff mode, the duty cycle of
  the slaves listen activity can be reduced. This
  means that the master can only start transmission
  in specified time slots.
• Hold mode While in connection state, the ACL
  link to a slave can be put in a hold (possible
  SCO links are still supported). In hold mode, the
  slave can do other things, such as scanning,
  paging, inquiring, or attending another piconet
  (scatternet scenario, see Section 3.1).
• Park mode If a slave does not need to
  participate in the piconet but still wants to
  remain synchronized to the channel (to
  participate in the piconet again later), it can
  enter the park mode. It gives up its active
  member address. Park mode is useful if there are
  more than seven devices that occasionally need to
  participate in the same piconet. The parked slave
  wakes up regularly to listen to the channel in
  order to re-synchronize and to check for
  broadcast messages sent by the master.

88
Bluetooth

• Bluetooth Profiles
• The Bluetooth Special Interest Group (SIG) has
  defined a number of usage models for Bluetooth
  technology.
• They describe the main Bluetooth applications and
  the intended devices, e.g., the synchronization
  between a handheld device and a PC, and
  connecting to the Internet wirelessly using a
  mobile phone or a cordless modem.
• Profiles specify how the interoperable solution
  for the functions described in the usage models
  is provided (defines the protocols and protocol
  features supporting a particular usage model).
• Some profiles are dependent on other profiles.
  For example, three profiles (File Transfer
  Profile, Object Push Profile, and Synchronization
  Profile) are dependent on the Generic Object
  Exchange Profile. All profiles are dependent on
  the Generic Access Profile, i.e., they are
  reusing it.

89
Bluetooth

• Bluetooth Profiles
• Bluetooth v1.1 profiles

90
Bluetooth

• Bluetooth Profiles
• The Four General Profiles in the Bluetooth
  Specification v1.1
• Generic Access Profile defines the generic
  procedures related to discovery of Bluetooth
  devices and link management aspects of connecting
  to Bluetooth devices.
• It also defines procedures related to use of
  different security levels.
• In addition, this profile includes common format
  requirements for parameters accessible on the
  user interface level.
• Every Bluetooth device has to support the Generic
  Access Profile.
• Service Discovery Application Profile defines the
  features and procedures for an application in a
  Bluetooth device to discover services of another
  Bluetooth device.
• Serial Port Profile defines the requirements for
  Bluetooth devices necessary for setting up
  emulated serial cable connections using RFCOMM
  between two peer devices.
• Generic Object Exchange Profile defines the
  protocols and procedures that will be used by
  applications that need object exchange
  capabilities. Possible scenarios are
  synchronization, file transfer, and object push.

91
Bluetooth

• Bluetooth Profiles
• Usage Model-Oriented Profiles
• Cordless Telephony Profile and Intercom Profile
  define the features and procedures required for
  interoperability between different units active
  in the "three-in-one phone" usage model (the same
  phone can be used as a cordless phone, a
  walkie-talkie, and a cellular phone).
• The Cordless Telephony Profile is used when the
  phone is connected to a base station of fixed
  telephony network via Bluetooth and the Intercom
  Profile implements so-called "walkie-talkie"
  usage between Bluetooth phones.
• Dial-Up Networking Profile describes how to use a
  cellular phone or a modem beside a computer as a
  wireless modem.
• Fax Profile defines how a computer can use a
  Bluetooth cellular phone or modem as a wireless
  fax modem to send or receive a fax.
• Headset Profile defines the requirements for
  Bluetooth devices necessary to support the
  headset use case. Wireless headsets can be used
  with cellular phones and laptops.

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Bluetooth

• Bluetooth Profiles
• Usage Model-Oriented Profiles ( Cont.)
• LAN Access Profile defines how Bluetooth-enabled
  devices can access the services of a local-area
  network.
• File Transfer Profile covers the scenarios that
  enable the user to browse and edit objects (files
  and folders) in the file system of another
  Bluetooth device and to transfer objects between
  two Bluetooth devices.
• Object Push Profile covers the scenarios that
  enable users to push, pull, and exchange simple
  objects such as business cards between two
  Bluetooth devices such as notebook PCs, PDAs, and
  mobile phones.
• Synchronization Profile covers the following
  scenarios PIM data exchange between two devices
  and automatic synchronization of data (e.g.,
  calendar items) when a device enters the
  proximity of the computer. Synchronization can be
  used between notebooks, PDAs, and mobile phones.

93
Bluetooth

• Bluetooth Profiles
• Additional Profiles
• To guarantee interoperability in many application
  areas, the working groups of the Bluetooth SIG
  are specifying new profiles.
• These will be published independently.
• Twelve additional profiles have already been
  published
• Generic Audio/Video Distribution Profile (GAVDP)
  defines a generic part of the protocols and
  procedures that realize distribution of
  audio/video content using ACL channels.
• Advanced Audio Distribution Profile (A2DP)
  defines distributing of audio content of high
  quality in mono or stereo on ACL channels. A2DP
  is dependent upon GAVDP.
• Audio/Video Remote Control Profile (AVRCP)
  defines transmission of a user-activated A/V
  control signal to a remote Bluetooth device.
• Basic Imaging Profile (BIP) is an OBEX-based
  profile that enables devices to negotiate the
  size and encoding of imaging data to be exchanged.

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Bluetooth

• Bluetooth Profiles
• Additional Profiles
• Basic Printing Profile (BPP) is an OBEX-based
  profile that enables printing of text e-mails,
  short messages, and formatted documents from
  mobile devices.
• Hardcopy Cable Replacement Profile (HCRP) is a
  lightweight profile implementation for printing
  and scanning any type of document. HCRP is
  implemented directly on top of L2CAP avoiding the
  overhead from OBEX, RFCOMM, or PAN.
• Bluetooth Extended Service Discovery Profile
  (ESDP) for Universal Plug and PlayTM (UPnPTM) is
  a profile for discovering other devices that
  support UPnP services and retrieve information
  about the services.
• Hands-Free Profile (HFP) defines a case where a
  mobile phone can be used in conjunction with a
  hands-free device (e.g., a car kit). HFP provides
  a wireless means for both remote control and
  voice connections
• Human Interface Device Profile (HID) defines
  usage of wireless keyboards, pointing devices,
  gaming devices, and remote monitoring devices.
• Common ISDN Access Profile defines how
  applications access ISDN over Bluetooth.
• Personal Area Networking Profile (PAN) defines
  IP-based personal networking. PAN also provides
  support for network access points (e.g., LAN or
  GSM).
• SIM Access Profile (SAP) defines how to access a
  SIM card via a Bluetooth link.

95
Bluetooth

• Bluetooth protocol stack v1.1

96
Bluetooth

• Bluetooth protocol stack v1.1
• Baseband and Link Control together enable a
  physical RF link between Bluetooth units forming
  a piconet. This layer is responsible for
  synchronizing the transmission-hopping frequency
  and clocks of different Bluetooth devices.
• Audio is routed directly to and from Baseband.
  Any two Bluetooth devices supporting audio can
  send and receive audio data between each other
  just by opening an audio link.
• Link Manager Protocol (LMP) is responsible for
  link set-up (authentication and encryption,
  control, and negotiation of baseband packets)
  between Bluetooth devices and for power modes and
  connection states of a Bluetooth unit.
• Logical Link Control and Adaptation Protocol
  (L2CAP) takes care of multiplexing, reassembly,
  and segmentation of packets.
• Service Discovery Protocol (SDP) is needed when
  requesting device information, services, and the
  characteristics of other devices. Devices have to
  support the same service in order to establish a
  connection with each other.

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Bluetooth

• Bluetooth protocol stack v1.1
• RFCOMM emulates RS-232 signals and can thus be
  used in applications that were formerly
  implemented with a serial cable (e.g., a
  connection between a laptop computer and a mobile
  phone).
• Telephony Control Protocol Binary (TCS-BIN)
  defines the call control signaling for the
  establishment of speech and data call between
  Bluetooth devices. AT commands provide means for
  controlling a mobile phone or a modem.
• OBEX (Object Exchange) is adopted from IrDA. It
  is a session protocol that provides means for
  simple and spontaneous object and data transfer.
  It is independent of the transport mechanism and
  transport Application Programming Interface
  (API).

98
Bluetooth