1. A Comparison of Bluetooth and competing technologies

2. Technologies
Bluetooth
IrDA
HomeRF

3. What we’ll talk about Purpose and Specifications
Communication Protocols and Network Topology
Disadvantages and Advantages in certain scenarios
Application comparison, consumer criteras, business analysts

4. Purpose Why Bluetooth? Why HomeRF? Why IrDA?
The Bluetooth specification is a global technology that allows wireless communication and networking between PCs and other portable devices.
Why HomeRF?
HomeRF enables different consumer electronic devices to communicate with each other while providing users with a complete home network solution. Users will be able to dial in from a remote location and control any device.
Why IrDA?
IrDA is intended for point-to-point links between two devices for simple data transfers and file synchronization.

5. Technical Specifications
Transmission Technology
Bluetooth & HomeRF: Radio Frequency
IrDA: Infrared Light Beams
Spectrum
Bluetooth & HomeRF: 2.45 GHz
IrDA: Optical

6. Technical Specification (cont.)
Connection Type
Bluetooth & HomeRF: spread spectrum
IrDA: Infrared, narrow beam
Data Rate
Bluetooth: 1 MB
HomeRF: 2 MB
IrDA: 4MB

7. Technical Specification (cont.)
Range
Bluetooth: 3 meters
HomeRF: 50 meters
IrDA: 1 meter
Maximum # of devices
Bluetooth: Up to 8 devices per piconet
HomeRF: Up to 127 devices per network
IrDA: 2 devices
Optimal Use
Bluetooth:
HomeRF: Home Networking
IrDA: Short Range: one-to-one data exchange

8. Communication Protocols
Provides what application are able to run.
Applications
RFCOMM / SDP
L2CAP
Host Controller Interface (HCI)
Link Manager (LM)
Baseband
Radio
RFCOMM: Provides emulation of serial ports over the L2CAP.
SDP: Provides a means for applications to discover which services are available and to determine the characteristics of those available services
Provides connection-oriented and connectionless data services to upper layer protocols with protocol multiplexing capability, segmentation, and reassembly operation and group abstractions.
Provides a command interface to the baseband controller and link manager, and access to hardware status and control registers.
Carries out link setup, authentication, link configuration, etc.
Manages physical channels and links (asynchronous and synchronous), handles packets, paging and inquiry to access Bluetooth devices in the area.
Bluetooth
Defines the requirements for the Bluetooth transceiver device.

9. Communication Protocols (cont.)
HomeRF uses, references and maps existing network layers.
Existing Upper Layers
TCP
UDP
DECT IP
HomeRF MAC Layer
HomeRF PHY Layer
MAC layer is optimized for the home environment and is designed to carry both voice and data traffic.
Good support for voice and data by using both TDMA and CSMA/CA access mechanisms.
Support for 4 high quality voice connections.
High data throughput 1.6Mbps.
Data security.
Power management for Isochronous and Asynchronous nodes.
24 bit Network ID.
Physical layer has been modified significantly to reduce cost, while still maintaining more than adequate performance for home usage scenarios .
Transmit power up to +24dBm
Receiver Sensitivity in 2FSK
Optional low power transmit mode: 0 to 4 dBm for portable devices.
HomeRF

10. Communication Protocol (cont).
Provides multiplexing of the IrLAP layer.
Multiple channels above an IrLAP connection
Provides protocol and service discovery by 121.
Infrared Link Management Protocol (IrLMP)
Infrared Link Access Protocol (IrLAP)
Physical Signaling Layer
Provides a device-to-device connection
Device discover procedures
Handles hidden nodes
Provides continuous operation from contact.
wireless point-to-point link between 2 independent nodes
Data packets are protected using a CRC.
Data transmission from 9600 b/s

11. Network Topology

12. Bluetooth Piconet and Scatternet
Piconet connects 7 devices with one host talking to 7 clients.
Clients have to talk to each other through the host.
Scatternet allows groups of piconets to communicate with each other.
Scatternet also has a host controlling groups of piconets.

13. Spectrum Collisions
HomeRF, Bluetooth, IEEE b use the same ISM 2.45 GHz frequency band.
If all 3 used in same vicinity, the technologies will disrupt and/or cancel each other.
With FHSS and different hop rates (Bluetooth hops/sec, HomeRF?) it minimizes the changes that they will interfere with each other.

14. HomeRF Interference Immunity
Frequency Hopping Spread Spectrum
Corruption happen only in small packets
High power transmission
Able to avoid some of the interfering frequency
Hopset adaptation makes sure that retry will be free of interference
Less consecutive “bad hops”

15. HomeRF Security
128-bit key encryption, 32-bit Initialization Vector(repeats every half a year)
Network ID needed to synchronize frequency hopping
Denial service attack unlikely
Disruptor must determine the frequency of HomeRF access point
Access points hop on independent sequences and time bases
HomeRF MAC ignores commands from foreign network IDs.

16. Advantage and Disadvantage of the three technologies: Bluetooth
Advantage of Bluetooth
Ad hoc connection
Better range than IR
Low power consumption
Connect through walls
Omnidirectional
Implemented by a large number of companies
Voice and data transmission
Disadvantage of Bluetooth
Low bandwidth
Interference
Collides with HomeRF
No Window XP support
New technology, buggy, not much tools
Current cost is high, $20
Radiation

17. Advantage and Disadvantage of the three technologies: HomeRF
Advantage of HomeRF
Security
Digital voice transmission
Peer to peer and host/client connection simultaneously
Interference immunity
Dedicated Internet/multimedia support
Disadvantage of HomeRF
Collides with Bluetooth and IEEE b
Competitor’s price coming down
Multimedia and telephony application not on market
Radiation

18. Advantage and Disadvantage of the three technologies: IrDA
Advantage of IrDA
Cheap $2
Compact, lightweight, low-power
Intuitive and easy to use
Noninterfering
Best ad hoc, point and shoot
Inherently more secure than RF
Disadvantage of IrDA
Line of sight only
Device cannot move around while transmitting
Point to point connection only
Short distance

19. Application usage: Bluetooth
Cell phone and PDA: Bluetooth
Needs filled by Bluetooth
Connect to multiple devices at the same time
Unconsciousness synchronization
Small, low energy consumption
Current implementation
Make Stylus into cell phone and keep PDA as base
Able to walk around the room while on the phone(stylus)

20. Application usage: Bluetooth
Cell phone and PDA: Bluetooth Cont.
Application can be platform and hardware independent
Bluetooth HCI (Host Control Interface) layer allows abstraction from hardware ie PCI card or USB adaptor
Java/JINI allows abstraction from OS
Bluetooth perfect for use in multiple devices connection on low bandwidth

21. Application usage: IrDA
E-Business cards: IrDA
Needs filled by IrDA
More secure than RF
Cheap
Easy to use
Interference free
Current implementation
Pint point who you want to share the business card with
Able to exchange information fast and very ad hoc, point and click

22. Application usage: IrDA
IrDA perfect for use in close proximity simple connection.
Calender, Address Book, Messages synchronizations

23. Application usage: HomeRF
Video conference: HomeRF
Needs filled by HomeRF
Support multiple digital voice lines
Transport voice and data simultaneously
Secure, encrypted messages
Higher interference resistance than Bluetooth
Multimedia and Internet support
Current implementation
Perform video conference across the Internet with dedicated support for both voice and data
Encrypt meeting with HomeRF security

24. Application usage: HomeRF
HomeRF perfect for use with multimedia devices.

25. Summary Bluetooth HomeRF IrDA RF Portable one-to-many network
Cell phone and PDA
HomeRF
Home and multimedia devices
Video conference
IrDA
Infrared
Portable one-to-one network
Calendar, address book, E business cards