A Comparison of Bluetooth and competing technologies

Technologies Bluetooth IrDA HomeRF

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

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.

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

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

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

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.

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

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

Network Topology

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.

Spectrum Collisions HomeRF, Bluetooth, IEEE 802.11b 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- 1600 hops/sec, HomeRF?) it minimizes the changes that they will interfere with each other.

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”

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.

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

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 802.11b Competitor’s price coming down Multimedia and telephony application not on market Radiation

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

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)

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

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

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

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

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

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