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  • 1.  
  • 2. Agenda
    • Introduction
      • Positioning of PAN/LAN/WAN
      • Wireless Local Area Network (WLAN) and 802.11
      • Personal Area Networks (PAN) and Bluetooth
    • Future Wireless Technologies
    • IBM Mobile Wireless Technology
  • 3. Penetration of Technology Opportunities for Connection
  • 4. Technology Positioning Person Space (office, briefcase, person) On-campus (Office, School, Airport, Hotel) Off-campus (Open areas) Cellular (Kilometers) 802.11b (10’s-100’s of meters) Bluetooth (meters to 10’s of meters) Geography Nomenclature Wireless Technology PAN LAN WAN
  • 5. 1. Wireless Local Area Networks (WLAN) 2. WLAN Components 3. IEEE 802.11 ? 4. Mixing Vendor Equipment 5. Wireless and wired LAN interoperability 6. WLAN Range 7. Access Points 8. Roaming 9. Using a WLAN to Interconnect two LANs 10. WLAN Scenarios 11. Security 12. Technology Comparisons WLAN Augment Wired LANs LAN Access Point Peer-to-peer collaboration Infrastructure Ad hoc
  • 6. Worldwide WLAN Sales ($ in Millions)
  • 7. Wireless Local Area Networks (WLAN)
    • Two or more computers connected wirelessly using standard network protocols
    • The current buzzword however generally refers to wireless LANs (WLAN).
    • Controlled by a standards committee (IEEE 802.11)
    • WLAN solutions for:
      • Business
      • Education
      • Applications where network wiring is impossible
        • Warehousing
        • Point-of-sale handheld equipment.
  • 8. WLAN Topologies
    • There are two kinds of wireless networks:
    • 1) An ad-hoc, or peer-to-peer wireless networks
      • Each computer communicates directly with each other to: send files, share printers, work collaboratively
      • They may not be able to access wired LAN resources, unless one of the computers acts as a bridge to the wired LAN using special software.
    • 2) Infrastructure wireless networks (access points, hardware or software)
      • Access point acts like a hub, providing connectivity for the wireless computers. It can connect (or "bridge") the wireless LAN to a wired LAN, allowing wireless computer access to LAN resources, such as file servers or the Internet.
  • 9. Infrastructure Dedicated hardware access points (HAP) Server Wired Network Wireless Network Wireless Clients Access Point Wired Client
  • 10. Infrastructure Software Access Points which run on a computer equipped with a wireless network interface card as used in an ad-hoc or peer-to-peer wireless network Wireless Client Server Wired Network Wireless Network Wireless Client Software Access Point Wired Client
  • 11. IEEE 802.11
    • Wireless networking hardware requires the use of underlying technology that deals with radio frequencies as well as data transmission .
    • The most widely used standard is 802.11 produced by the Institute of Electrical and Electronic Engineers (IEEE).
    • This is a standard defining all aspects of Radio Frequency Wireless networking.
    • 802.11 was ratified in 1997 at speeds of 1- 2 Mb/s
    • The 802.11b extension runs at 1, 2, 5.5 and 11 Mb/s
  • 12. IEEE 802.11
    • 802.11a is a proposed spec running in the 5GHz IBM band with speeds of 54Mb/s scheduled for 2002
      • But range is less (more like 10m)
    • The 802.15 Coexistence Task Group is addressing interoperability between low-power wireless devices (Bluetooth) and 802.11b. Completion is scheduled for 2001
    • IBM is a member of 802.11 and 802.15
  • 13. Mixing vendor equipment
    • Because most wireless networking hardware vendors support the 802.11 standard they can inter-operate.
    • Verification is recommended because there are two different modulation techniques:
      • Frequency Hopping Spread Spectrum (FHSS)
      • Direct Sequence Spread Spectrum (DSSS)
      • They are not interoperable.
    • When purchasing wireless networking hardware from separate vendors be sure to obtain guarantees from the vendors that the hardware will inter-operate and follows the standards.
  • 14. Mixing vendor equipment
    • Within a short time all new wireless cards, like Ethernet cards, will become inexpensive, ubiquitous and totally interoperable .
    • The latest version of the standard (802.11b) defines 11mbps with support for the older standard of 1mbps and 2mbps speeds. This provides compatibility with different or older equipment.
    • Note that this new standard covers DS-type Networks, not FH types .
    • At this point mixing Access Points is not recommended, unless it has the Wi-Fi (Wireless Fidelity)
    • logo from WECA (Wireless Ethernet Compatibility Association)
  • 15. Wireless and Wired LAN Interoperability
    • The Access Point acts as a “Bridge” between the wireless and wired networks
    • Hardware access points are available with various types of network interfaces, such as Ethernet or Token Ring
    • Software access point may also be used
  • 16. WLAN Range
    • Each access point has a finite range
    • The distance varies depending upon the environment; indoor, outdoor, building construction.
    • Operating at the limits of the range reduces performance .
    • Typical indoor ranges are 20-50 meters, outdoor are 100-200 meters
    • Longer ranges are possible; performance will degrade with distance.
    • Using multiple Access Points will extend the range
  • 17. Access Points
    • Inexpensive access points have a recommended limit of 10
    • More expensive access points support up to 100 wireless connections.
    • Using more computers than recommended will degrade performance and reliability
    • Multiple access points can be connected to a wired LAN, or to a second WLAN.
    • Functions vary by manufacturer
  • 18. Roaming
    • A wireless computer can "roam" from one access point to another
    • Completely transparent to the user
    • Some access point configurations require security authentication when swapping access points, usually in the form of a password dialog box.
    • Access points are required to have overlapping wireless areas to achieve this.
  • 19. Using a WLAN to interconnect two LANs
    • WLAN offers a cost-effective solution to users with difficult physical installations such as:
      • campuses
      • hospitals
      • businesses with more than one location in immediate proximity but separated by public thoroughfare.
    • This type of installation requires two access points .
    • Each access point acts as a bridge or router connecting its own LAN to the wireless connection.
    • The wireless connection allows the two access points to communicate with each other, and therefore interconnect the two LAN's.
  • 20. WLAN Scenarios
    • Mobile users , both on and off “campus”
    • Where physical wiring is difficult or impossible
    • Connecting small groups to a larger work environment.
    • Wireless networking in these environments is a very cost effective alternative
    • Temporary wireless LANs can easily be created for exhibitions, school or business projects, all without any trailing cabling.
  • 21. Security
    • Potential security issues; physical access not required.
    • 802.11 wireless communications cannot be received nor decoded by simple scanners or short wave receivers.
    • However, eavesdropping is possible using special equipment.
    • 802.11 WLAN have a function called WEP (Wired Equivalent Privacy); a form of encryption.
    • Access Points can control access via unique MAC addresses.
    • Virtual Private Networking (VPN) techniques will work over wireless networks in the same way as traditional wired networks. This is the best approach.
  • 22. WLAN Security: SSID
    • Network access control can be implemented using an SSID associated with an AP or group of APs.
    • The SSID provides a mechanism to "segment" a wireless network into multiple networks serviced by one or more APs.
    • Each AP is programmed with an SSID corresponding to a specific wireless network.
    • To access this network, client computers must be configured with the correct SSID.
    • The SSID acts as a simple password
  • 23. WLAN Security: MAC Filtering
    • A client computer can be identified by the unique MAC address of its 802.11 network card.
    • Each AP can be programmed with a list of MAC addresses associated with the client computers allowed to access the AP.
    • If a client's MAC address is not included in this list, the client is not allowed to associate with the AP.  
    • MAC address filtering provides good security , but is best suited to small networks.
    • Each AP must be manually programmed with a list of MAC addresses, and the list must be kept up-to-date.
  • 24. WLAN Security: WEP
    • WEP provides encrypted communication
    • All clients and APs on a wireless network use the same key
    • The key resides in the client computer and in each AP
    • Support for WEP is standard
    • WEP specifies the use of a 64-bit encryption key
    • Implementations of non-Wi-Fi 128-bit key encryption exists
    • The 802.11 standard does not specify a key management protocol, so all keys on a network must be managed manually
  • 25. WLAN Security: VPN
    • A VPN solution for wireless access is the most suitable alternative to WEP and MAC address filtering.
    • VPN solutions are already widely deployed to provide remote workers with secure access to the network via the Internet.
    • In this remote user application, the VPN provides a secure , dedicated path (or "tunnel") over an "untrusted" network-in this case, the Internet.
    • Various tunneling protocols are used in conjunction with standard, centralized authentication solutions,such as Remote Authentication Dial-In User Service ( RADIUS ) servers.
  • 26. WLAN Security: VPN
    • VPN technology can also be used for secure wireless access ; the "untrusted" network is the wireless network.
    • The APs are configured for open access with no WEP encryption , but wireless access is isolated from the enterprise network by the VPN server and a VLAN between the APs and the VPN servers.
    • The APs should still be configured with SSIDs for segmentation.
    • Authentication and full encryption over the wireless network is provided through the VPN servers that also act as gateways.
    • Unlike the WEP key and MAC address filtering approaches, the VPN-based solution is scalable to a very large number of users.  
    Section End
  • 27. Personal Area Networks (PAN) and Bluetooth 1. What is Bluetooth? 2. Characteristics? 3. Usage scenarios: Today/Tomorrow? 4. 802.11 vs. Bluetooth vs. IR 5. Security 6. IBM’s Contribution Cell phone Modem Access Point Peripherals ThinkPad Personal Area “Connectivity” WorkPad
  • 28. What is Bluetooth.... Defacto standard for wireless Personal Connectivity technology Specification for small -form factor, low -cost, short range radio links between mobile PCs, mobile phones and other portable devices. The Bluetooth Special Interest Group (SIG) is an industry group consisting of leaders in the telecommunications and computing industries that are driving development of the technology and bringing it to market. IBM, Toshiba, Ericsson, Nokia, Intel - Motorola, Microsoft, Lucent and 3Com - plus 2000+ other companies
  • 29. Bluetooth Market Potential W/W Bluetooth Enabled Equipment Forecast (Units in Millions) Source : Cahners In Stat July 2000
  • 30. Characteristics
    • Operates in the 2.4 GHz Industrial-Scientific-Medical (ISM) band at a data rate of 721Kb/s
    • Uses Frequency Hopping (FH) spread spectrum , which divides the frequency band into a number of channels (2.402 - 2.480 GHz yielding 79 channels). 1600 hops/sec.
    • During a connection, radio transceivers hop from one channel to another in a pseudo-random fashion, determined by the Master .
    • Supports up to 8 devices in a piconet (1 master and up to 7 slaves sharing a channel).
    • Up to 10 piconets can combine to form scatternets (scaling).
  • 31. Piconets/Scatternets
    • A collection of devices
    • Connected via Bluetooth in an ad hoc fashion.
    • Starts with two devices, and may grow to eight (including the master)
    • Master sets the clock and hopping pattern.
    • However, when establishing a piconet, one unit will act as a master and the other(s) as slave (s) for the duration of the piconet connection.
    • A Scatternet is the linking of multiple co-located piconets through the sharing of common master or slave devices.
  • 32. Characteristics
    • Built-in security.
    • Non line-of-sight transmission through walls and briefcases .
    • Omni-directional .
    • Supports both voice and data services; easy integration of Serial links and TCP/IP for networking
    • Regulated by governments worldwide, even France !
    • Supports both one-to-one and one-to-many networking topologies
    • Devices must be in a 10 meter radius for communications to occur.
  • 33. Bluetooth Protocol Stack WAE WAP vCard/vCal Obex TCP/ UDP IP PPP RFComm Service Discovery Audio L2CAP BaseBand Telephony Control Radio HCI LMP Lower Transport Upper Transport Middleware Adopted
  • 34. Network Topologies
    • One-to-one
    • One-to-many
    (generally Serial mode) (generally TCP/IP mode)
  • 35. Key Notebook Usage Models Dial-up Networking Synchronization File Transfer
    • Bluetooth Usage Models for Notebooks
      • Dial-Up Networking via cell phone
      • Syncing
      • File Transfer
    • Target Devices
      • Cellphone
      • Desktop
      • Handheld
      • Other Notebook
  • 36. Key Handheld Usage Models Dial-up Networking Synchronization File Transfer
    • Bluetooth Usage Models for Handhelds
      • Dial-up Networking via Cell phone
      • Syncing
      • File Transfer (business cards)
      • Target Devices
      • Cell phone
      • Desktop
      • Notebook
      • Other handheld
  • 37. Key Desktop Usage Models Synchronization File Transfer
    • Bluetooth Usage Models for Desktop
      • Syncing
      • File Transfer
      • Lan Access for
      • devices
    • Target Devices
      • Handheld
      • Notebook
  • 38. Other Usage Scenarios Telephony Infrastructure Data Access Points Headset
  • 39. Bluetooth Access to WAN
    • A computer network that spans a relatively large geographical area.
    • Typically, a WAN consists of two or more local-area networks (LANs).
    • Computers connected to a WAN are often connected through PSTNs . They can also be connected through leased lines or satellites . The largest WAN in existence is the Internet .
  • 40. Future Usage Scenarios Personal Area Networking Automotive Wake on Bluetooth Human Interface Devices Audio/Visual Walk-up Printing Hidden Computing Instant Postcard Multi-Piconet Cordless Computer Intercom FAX LAN Access Headset Multi-Point Dial-Up Networking File Transfer Synchronization Point to Point Ease-of-Use Today Tomorrow The Future
  • 41. Future Usage Scenarios Adds weight and cost Decreases reliability Standard Connectivity
    • Today: Many Cable Connections
      • Serial
      • Parallel
      • Mouse
      • Keyboard
      • Floppy
      • Audio
      • IR
      • USB
      • Video
      • Docking
      • Power
  • 42. Future Usage Scenarios Adds weight and cost Decreases reliability
    • Tomorrow: Fewer Cables
    • Bluetooth
      • USB
      • Video
      • Docking
      • Power
    Reduces weight and cost Increases reliability Standard Connectivity
    • Today: Many Cable Connections
      • Serial
      • Parallel
      • Mouse
      • Keyboard
      • Floppy
      • Audio
      • IR
      • USB
      • Video
      • Docking
      • Power
  • 43. Future Usage Scenarios Personal Area Networking
    • Spontaneous / ad-hoc networking
      • Computer Supported Cooperative Work
      • (CSCW) environments
      • Workgroup collaboration
    • Between many different devices
      • PC, PDA, Printer,
      • Mobile phone , Communicator,
      • Digital Camera (Still & Video)
      • Digital TV, MP3 Player
      • etc…
    • Slave-to-slave communication
    • is through the master
  • 44. Prototype work by Pervasive group
    • Walk up “push” of adverts and services.
    • Demo uses IBM Research Blue Drekar stack available from Alphaworks.
    • Contact Yook Siong Chin.
  • 45. Location Aware Services
    • NOT Location Based Services
      • eg - Where is nearest xyz ?
      • Pay for vending.
    • But AWARE of the user
      • anticipate needs
      • prepare and be ready to interact
      • only need to know that the user is present
        • or indeed no longer present
      • Bluetooth device eg Phone or PDA is ideal.
        • Carried with user
        • Individual
  • 46. Total effect = real ease of use
    • Come into office
      • PC unlocks
      • Buddy status says user at desk
      • Phone calls go to desk phone
    • Go to lab
      • Office PC locks up
      • Buddy status says away from desk
      • Lab lights turn on
      • Phone calls go to lab
    • Go to lunch
      • lab lights go off
      • phone calls go to mobile
    • Go back to office
      • PC unlocks
      • Buddy status says user at desk
      • Phone calls go to desk phone
    • etc...
    Without pressing a single button !
  • 47. Security
    • Unique MAC address for every Bluetooth device
    • Bluetooth has built-in encryption and authentication
    • In addition a frequency-hopping scheme with 1600 hops/sec is employed.
    • All of this, together with an automatic output power adaptation to reduce the range exactly to requirement, makes the system extremely difficult to eavesdrop
  • 48.
    • Security mode 1 (non-secure).
      • A device does not initiate any security procedures.
    • Security mode 2 (service-level enforcement security).
      • A device does not initiate security procedures before channel establishment at the service level. This mode allows different and flexible access policies for applications, and is used especially for running applications with different security requirements in parallel.
    • Security mode 3 (link-level enforced security).
      • A device allows only authenticated connections.
    • Bluetooth technology has three security attributes
      • Authorization
      • Authentication
      • Encryption.
    Security Implementations
  • 49.
    • Authorization
      • Database of services which a device has authorization to use
    • Authentication
      • The user can choose to "auto" trust devices or "manually" trust devices.
      • Authentication is accomplished using a challenge-response scheme using symmetric link keys.
      • If the devices do not share a link key, one is created through a process called "pairing" and based on a shared secret association, like a PIN code .
      • If a device does not have a mechanism to enter a PIN, a restricted form link key, called a unit key, is generated based on the device's address and random number.
    • Encryption can only be activated after authentication. Encryption is based on a stream cipher easily implemented in hardware or software.
    Security Implementations
  • 50. IBM's Contribution to the SIG Section End
    • IBM is one of the original 5 founding members.
    • IBM authored the discovery protocol (discovery protocol is a method to explore and discovery Bluetooth devices and services within range)
    • IBM contributed to the lower layer protocol that makes up the entire Bluetooth protocol stack (link level protocol)
    • IBM contributed to the Bluetooth world-wide regulatory working bodies to harmonize the 2.4GHz frequency spectrum use for Bluetooth and other government agency requirements.
    • IBM funds and contributes to many of the the organization’s events.
    • IBM is leading the effort to standardize IEEE 802.15, which will embrace Bluetooth as a short range wireless standard.
  • 51. 802.11 vs. BT vs. IR vs. HRF
  • 52. Which Technology is Better? For connecting devices in your What do you want to do? For connecting clients to your ) ) ) Campus wide or someone else’s “ Personal Domain”... Bluetooth is the right choice LAN Infrastructure... ) ) ) Airport/Hotel or a public one 802.11b WLAN is the right choice
  • 53. Which Technology is Better? For creating an ad hoc Peer-to-Peer Network Either would suffice Bluetooth: One-to-many 802.11b: Many-to-many
    • Consider:
      • Technology install base
      • Size of the workgroup
      • Extent of the CSCW effort
    (Computer Supported Cooperative Work)
  • 54. Other Wireless Technologies http://www.research.ibm.com/journal/sj/384/zimmerman.html Infrared Data Association (IrDA) for laptops Directional or high power Simple, inexpensive, no regulations 1 1000 Light Optical infrared (high data rate) Home remote control Directional Simple, very inexpensive, no regulations 10 10 Light Optical infrared (low data rate) Data networking Cost, power International, fast 10-100 1000 2400 RF microwave ISM Access control, telecommand Local regulations Low cost, efficient for distance 30 40 300-500 RF UHF Picocells data messaging Antenna size Signal goes through body, international use 6 250 5 Magnetic field Identification Signal blocked by body, grounded objects Capacitive coupling limits range, data transmitted by touch, international use 2 20 0.1-1 Electric field Application Problems Advantages Range (m) Maximum Bit Rate (Kbps) Carrier Frequency ( MHz )
  • 55. UWB – Impulse Radio
    • Ultra Wide Band
      • Uses picosecond mono-pulses
        • Creates very wide radio spectrum
        • Down in noise floor (-30 to -60dB)
      • Requires very accurate timebase
        • Normally based on PPM techniques
      • But can deliver high data rates (80+ Mbs)
      • At very low power ( µ W)
    Fourier Transform of infinitely narrow pulse = infinitely wide frequency spectrum t f ≡
  • 56. Example: Pulse-LINK ™ Pulse~LINK, Inc. http://www.pulselink.net/
    • 80Mbs
    • 150m
  • 57. UWB
    • Currently used in military applications
    • Squirt radios
      • Difficult to detect / intercept
      • Low power for data rate means more portable
    • Pulsed Radar
      • Can “see through” obstacles
      • Difficult to detect and protect against
    • Not licensed for public use
      • Cuts across most currently licensed bands
      • Backers claim no need as there will be no interference to normal equipment
      • Others doubt that – they say the background noise will increase and some frequencies may be more impacted than others as pulses are not true impulse shape
  • 58. UWB
    • Wide frequency range helps with transmission through obstacles
      • Like bodies, walls, furniture
      • Harder to shield against
      • Helps Omni-directional transmission
    • No studies on health implications
      • Although very low power – what are the effects of continuous impulses across wide freq range ?
  • 59. Smart Dust
    • Target is sub mm sized devices
    • Free floating in air
    • Containing sensors
      • Temp, acceleration, pressure, chemical, etc
    • And communications to other particles
      • 5 – 10 m range
      • 20kbs
      • 900MHz radio
      • Or km range via laser
    http://robotics.eecs.berkeley.edu/~pister/SmartDust/
  • 60. The Challenge for Wearables
    • Need to interconnect components
    • & connect within PAN to other devices
    • & connect outside of PAN
    UWB has lots of promise – low power – data rates high enough But no real interoperability standards between devices Not many off the shelf components – expensive (for now) Hign frequencies mean CMOS fab unlikely Probably needs to support existing standards Most likely Bluetooth But devices may will switch to UWB or similar Definitely needs to support existing standards Maybe via CPU point 802.11b/a too power hungry for WAN wearable use Section End
  • 61. IBM Wireless Technologies 1) Bluetooth: PC Card and ThinkPad UltraPort 2) 802.11b PC Card, ThinkPad UltraPort and Access Point 3) ThinkPad and WorkPad Proven products 4) Other products “available”
  • 62. 802.11b IBM High Rate Wireless LAN Access Point
    • £127 list price - 128bit
    • £105 list price - 64 bit
    • Plugs into the ThinkPad’s CardBus slot
    • Provides wireless access to corporate LAN from anywhere within a 45-90m radius
    • Supports speeds from 2 to 11 Mbps
    • 64 bit encryption (WEP) or 128 bit
    IBM High Rate Wireless LAN PC Card
    • £486 IBM Web price
    • Bridges to the wired corporate LAN
    • Allows the user to roam within coverage area
    • Can support multiple users
  • 63. Bluetooth Bluetooth PC Card For Legacy Devices 09n9812 Bluetooth UltraPort For Optimal Performance 09n9811
    • Designed to replace peripheral cables for PDAs, printers, cameras, etc.
    • Designed for personal space connectivity
    • Connectivity range of 10 meters
    • Nominal data rate of 1 Mb/s
    • Built-in encryption
    Ann: 9/5 GA: October Ann: 1Q 2001 £143 list price £127 list price
  • 64. Cellular Phone BT Options
    • Wireless access to Internet and corporate networks
    • Wireless connection to ThinkPad
    • Non-directional; phone can be in your briefcase
    • Wirelessly update your phone’s address book from your system
    • Insulates you from rapid changes in cellular networks
    Ericsson Cell Phone Bluetooth Module Ericsson Headset R520m, T39m
  • 65. Bluetooth Options Section End Nokia Bluetooth “ battery” for 6210 & CF 1 card GN Netcom 9000 Headset TDK Blue5 clip for PalmV
  • 66. IBM Research Protoype This is NOT a product Linux based watch / pda “ Watchpad”
    • Runs X-clock really well !
    • Also now includes Bluetooth
    • Supports Sync , DUN and Audio
    • Current demos include PIM sync, and control of PC.
  • 67. Shrinking Components – Disk Drives
    • 1 GB is :
      • 2500 high resolution photos, or
      • 1000 200 page books, or
      • 18 hours high quality music.
    • 1980 – IBM Launches 1 st GB Disk
      • Size of a Refrigerator
      • Weighs 250 kg
      • Costs $40,000
    • 2000 – IBM Launches 1 st GB Micro Drive
      • Size of Coin
      • Weighs 25 g
      • Costs < $500
  • 68. Devices that Answer Back . . . !
    • Standard Palm Pilot
    • Speech Co-Processor
      • Speech to Text
      • Text to Speech
    • Technology Demonstrator
    • Progressing with Device Manufacturers
    • Now runs on standard hPaq
    Replies by Showing & Speaking Information Ask Question
  • 69. IBM Prototype wearable
  • 70. Visual Interaction
    • Vision Pad prototype:
      • Transparent head mounted display
      • Handheld controller
      • Speech input
    • Augmented reality concept – sign recognition and translation
  • 71. Resources
    • IBM Pervasive Computing
      • http://www.ibm.com/pvc
    • Bluetooth SIG
      • http://www.bluetooth.com
    • Shameless Plug for Book
      • Bluetooth Revealed, published by Prentice-Hall, September 2000
    • AU-Systems - good Bluetooth White Paper
      • http://www.ausys.se/servlet/PSPDownloadServlet?iListItemId=6833
    • UWB – Impulse Radio
      • http:// www.uwb.org
  • 72. Questions ? ? ? ? ?