Bluetooth and Bluetooth Networking

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Bluetooth and Bluetooth Networking

• Nathan Bruker
• IXI Mobile
• June 2003

November 2002
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Bluetooth Overview

• Bluetooth wireless technology is a universal
  Ad-Hoc conectivity method
• Low power (0dBm, 10m) Low cost (lt5)
• Typically used for cable replacement, enabling
  links between mobile computers, mobile phones,
  portable handheld devices, and connectivity to
  the Internet.
• Voice and Data services
• Unlicensed technology in the ISM RF band
• The Bluetooth SIG controls the specifications
  http//www.Bluetooth.org

Harald Bluetooth was king of Denmark in the late
900s. He managed to unite Denmark and part of
Norway into a single kingdom Choosing this name
for the standard indicates how important
companies from the Baltic region (nations
including Denmark, Sweden, Norway and Finland)
are to the communications industry, even if it
says little about the way the technology works.
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Bluetooth Scenarios

• The briefcase
• dialup

• headset

• LAN Access

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Bluetooth Networks Piconet

• Collection of devices connected in an ad hoc
  fashion
• One unit acts as master and the others as slaves
  for the lifetime of the piconet
• Master determines hopping pattern, Slaves have to
  synchronize
• Each piconet has a unique hopping pattern
• Participation in a piconet synchronization to
  hopping sequence
• Each piconet has one master and up to 7
  simultaneous slaves (gt 200 could be parked)

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Forming A piconet

• All devices in a piconet hop together
• Master gives slaves its clock and device ID
• Hopping pattern determined by device ID (48 bit,
  unique worldwide)
• Phase in hopping pattern determined by clock
• Addressing
• Active Member Address (AMA, 3 bit)
• Parked Member Address (PMA, 8 bit)

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Scatternet

• Linking of multiple co-located piconets through
  the sharing of common master or slave devices
• Devices can be slave in one piconet and master of
  another
• Devices jumping back and forth between the
  piconets

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Bluetooth layers
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Bluetooth Baseband

• Piconet/channel definition
• Low-level packet definition
• Access code
• Channel, device access, e.g., derived from master
• Packet header
• 1/3-FEC, active member address (1 master, 7
  slaves), link type, alternating bit ARQ/SEQ,
  checksum

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Baseband States of BT device
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Base Band Link Types

• Polling-based TDD packet transmission
• 625µs slots, master polls slaves
• SCO (Synchronous Connection Oriented) Voice
• Periodic single slot packet assignment, 64 kbit/s
  full-duplex, point-to-point
• ACL (Asynchronous ConnectionLess) Data
• Variable packet size (1,3,5 slots), asymmetric
  bandwidth, point-to multipoint

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Security
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L2CAP - Logical Link Control and Adaptation
Protocol

• Simple data link protocol on top of baseband
• Connection oriented, connectionless, and
  signaling channels
• Protocol multiplexing
• RFCOMM, SDP, telephony control
• Segmentation reassembly
• Up to 64kbyte user data, 16 bit CRC
• QoS flow specification per channel
• Follows RFC 1363, specifies delay, jitter,
  bursts, bandwidth
• Group abstraction
• Create/close group, add/remove member

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SDP Service Discovery Protocol

• Inquiry/response protocol for discovering
  services
• Searching for and browsing services in radio
  proximity
• Adapted to the highly dynamic environment
• Defines discovery only, not the usage of services
• Caching of discovered services
• Service record format
• Information about services provided by attributes
• Attributes are composed of an 16 bit ID (name)
  and a value
• IDs may be derived from 128 bit Universally
  Unique Identifiers (UUID)

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Profiles

• Represent default solutions for a certain usage
  model
• Vertical slice through the protocol stack
• Basis for interoperability
• Generic Access Profile
• Service Discovery Application Profile
• Cordless Telephony Profile
• Intercom Profile
• Serial Port Profile
• Headset Profile
• Dial-up Networking Profile
• Fax Profile
• LAN Access Profile
• Generic Object Exchange Profile
• Object Push Profile
• File Transfer Profile
• Synchronization Profile

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Bluetooth Networking in Fixed networks
BT Access point
LAP
Fixed IP address
Roaming
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Wireless Personal Area Network (PAN)
BSC/MSC
SGSN
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Challenges of BT/GPRS based PAN

• SGSN Assign temporary IP address
• Only a single object in the network can be
  assigned with address (or multiple subscription
  are required
• The IP is temporary and the contract for it can
  be limited in time
• Problems in terminating an IP session within the
  network
• Typical BT profiles will not handle point to
  multipoint communication in this environment
• Most Profiles are cable replacements
• LAN profile will not work in wireless environment
• No standardization for network resources
  (server)
• Shared storage
• Shared plug-ins and applications
• BT is a physical pipeline not a standard
  application environment
• Profiles are a partial solution only

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IXI Mobile Personal Mobile Gateway
Remote management
Sleek Devices
Personal Mobile Gateway

• Targeted device per application
• Variety broad consumer base

• Remote apps. download
• Users statistics devices monitoring

• Bridges services to devices
• Enables expansion upgrades
• Solve True networking issues

PAN (e.g. Bluetooth)
Cellular (2.5G or 3G)
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PMG Architecture IXI-Connect
PMG HW
PMG SW
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Bluetooth Phone vs. PMG PhoneSummary

• Bluetooth
• Introducing new PAN terminals
• End-user bluetooth experience
• PAN Management
• Supports Thin Terminals
• Content Sharing
• Common Database
• Private IP Concurrent Usage
• Operator Visibility Control

Yes Complex Complex No No No No No No
Yes Simple Simple Yes Yes Yes Yes Yes Yes
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